文章
Miss Chen
2018年08月06日
Description: This is a biennial plant. During the 1st year, it consists of a rosette of basal leaves spanning about ¾–1½' across. During the 2nd year, it produces a flowering stalk that becomes 3-7' tall, branching occasionally above. The stems are round, glabrous, light green, and purple-spotted; they often appear to be ribbed because of longitudinal veins. The alternate leaves are up to 18" long and 12" across, becoming smaller as they ascend the stems. They are double or triple pinnately compound, triangular-ovate in outline, and hairless. These leaves have a fern-like appearance and a somewhat filmy upper surface. The basal and lower leaves have long petioles, while the upper leaves have shorter petioles. The base of each petiole is partially covered by a sheath. The ultimate leaflets of the compound leaves are about 1/3" (8 mm.) long, lanceolate to ovate in shape, pinnately cleft or dentate, and hairless.
The upper stems terminate in compound umbels of small white flowers. These compound umbels span about 2-5" across and consist of about 8-16 umbellets. Each umbellet consists of about 12-25 flowers. Individual flowers span only 1/8" (3 mm.) across when they are fully open. Each flower has 5 white obcordate petals, 5 spreading white stamens, and a white nectar pad in the center. At the base of the compound umbel are several floral bracts that are ovate-lanceolate with elongated tips; there are also several bractlets at the base of each umbel. These bractlets are ovate-lanceolate like the bracts, but smaller in size. The blooming period occurs from late spring to mid-summer and lasts about 1-2 months. Each flower is replaced by a schizocarp that is broadly ovate and somewhat flattened; it has several longitudinal ribs that are wavy. The root system consists of a white taproot. This plant spreads by reseeding itself; it often forms colonies at favorable sites.
Cultivation: The preference is full sun to light shade, moist conditions, and a fertile loamy soil. Most vegetative growth occurs during the spring. After blooming and developing seeds, the foliage turns yellow and withers away later in the summer. In removing this plant from a given area, don't pull it out using your bare hands. It is better to wear washable gloves while hand-pulling a limited number of plants. For large areas of infestation, it is best to apply broadleaf herbicides or mow down the plants during the spring shortly before they develop flowers.
Range & Habitat: Poison Hemlock is a common plant that occurs in many areas of Illinois, except for scattered counties in north and south (see Distribution Map). This plant is undoubtedly more common than official records indicate and it is still spreading to new areas of the state. Poison Hemlock is native to Europe and the Middle East, and it was introduced into North America either accidentally or deliberately.
Habitats include edges of degraded wetlands and prairies, low-lying areas along small rivers, banks of drainage ditches, thickets, woodland borders, fence rows, low-lying areas along railroads and roads, pastures, and abandoned fields. This plant is usually found in disturbed areas, but it occasionally invades native habitats.
Faunal Associations: The nectar of the flowers attracts a wide variety of flies, beetles, sawflies, and wasps, including Ichneumonid and other parasitoid wasps. Caterpillars of the butterfly, Papilio polyxenes asterius (Eastern Black Swallowtail), feed on the foliage, notwithstanding its extreme toxicity (personal observation). This toxicity is the result of the alkaloid coniine and other chemicals, which can be found in all parts of Poison Hemlock, including the seeds and roots. Another insect, Orthops scutellatus (Carrot Plant Bug), eats the seeds of this plant and other members of the Carrot family (Knight, 1941). Poison Hemlock is also a summer host plant of several aphids, including Dysaphis apiifolia (Hawthorn-Parsley Aphid), Hyadaphis foeniculi (Fennel Aphid), and Hyadaphis passerinii (Honeysuckle Aphid); see Blackman & Eastop (2013). Mammalian herbivores won't touch the foliage because of its bitter rank odor and extreme toxicity. Just a small portion of the ingested plant can be fatal to humans.
Comments: The ancient Athenians used the juices of this plant to execute their prisoners, including Socrates during 399 B.C. Death is caused by respiratory arrest and heart failure. Poison Hemlock is a tall and imposing plant that appears to be increasingly common. Many people walk past this species without even realizing what it is. Because there are many members of the Carrot family with small white flowers, it can be somewhat difficult to correctly identify this plant. Poison Hemlock has the following key features: 1) it is often tall-growing, 1) the foliage is at least double pinnate and fern-like in appearance, 2) the foliage has a bitter rank odor, especially when it is bruised, 3) the hairless stems have purple spots, 4) there are undivided bracts at the base of the compound umbel and undivided bractlets at the base of the umbellets, and 5) the small leaflets are pinnately cleft or dentate. Other members of the Carrot family lack one or more of these key features.
The upper stems terminate in compound umbels of small white flowers. These compound umbels span about 2-5" across and consist of about 8-16 umbellets. Each umbellet consists of about 12-25 flowers. Individual flowers span only 1/8" (3 mm.) across when they are fully open. Each flower has 5 white obcordate petals, 5 spreading white stamens, and a white nectar pad in the center. At the base of the compound umbel are several floral bracts that are ovate-lanceolate with elongated tips; there are also several bractlets at the base of each umbel. These bractlets are ovate-lanceolate like the bracts, but smaller in size. The blooming period occurs from late spring to mid-summer and lasts about 1-2 months. Each flower is replaced by a schizocarp that is broadly ovate and somewhat flattened; it has several longitudinal ribs that are wavy. The root system consists of a white taproot. This plant spreads by reseeding itself; it often forms colonies at favorable sites.
Cultivation: The preference is full sun to light shade, moist conditions, and a fertile loamy soil. Most vegetative growth occurs during the spring. After blooming and developing seeds, the foliage turns yellow and withers away later in the summer. In removing this plant from a given area, don't pull it out using your bare hands. It is better to wear washable gloves while hand-pulling a limited number of plants. For large areas of infestation, it is best to apply broadleaf herbicides or mow down the plants during the spring shortly before they develop flowers.
Range & Habitat: Poison Hemlock is a common plant that occurs in many areas of Illinois, except for scattered counties in north and south (see Distribution Map). This plant is undoubtedly more common than official records indicate and it is still spreading to new areas of the state. Poison Hemlock is native to Europe and the Middle East, and it was introduced into North America either accidentally or deliberately.
Habitats include edges of degraded wetlands and prairies, low-lying areas along small rivers, banks of drainage ditches, thickets, woodland borders, fence rows, low-lying areas along railroads and roads, pastures, and abandoned fields. This plant is usually found in disturbed areas, but it occasionally invades native habitats.
Faunal Associations: The nectar of the flowers attracts a wide variety of flies, beetles, sawflies, and wasps, including Ichneumonid and other parasitoid wasps. Caterpillars of the butterfly, Papilio polyxenes asterius (Eastern Black Swallowtail), feed on the foliage, notwithstanding its extreme toxicity (personal observation). This toxicity is the result of the alkaloid coniine and other chemicals, which can be found in all parts of Poison Hemlock, including the seeds and roots. Another insect, Orthops scutellatus (Carrot Plant Bug), eats the seeds of this plant and other members of the Carrot family (Knight, 1941). Poison Hemlock is also a summer host plant of several aphids, including Dysaphis apiifolia (Hawthorn-Parsley Aphid), Hyadaphis foeniculi (Fennel Aphid), and Hyadaphis passerinii (Honeysuckle Aphid); see Blackman & Eastop (2013). Mammalian herbivores won't touch the foliage because of its bitter rank odor and extreme toxicity. Just a small portion of the ingested plant can be fatal to humans.
Comments: The ancient Athenians used the juices of this plant to execute their prisoners, including Socrates during 399 B.C. Death is caused by respiratory arrest and heart failure. Poison Hemlock is a tall and imposing plant that appears to be increasingly common. Many people walk past this species without even realizing what it is. Because there are many members of the Carrot family with small white flowers, it can be somewhat difficult to correctly identify this plant. Poison Hemlock has the following key features: 1) it is often tall-growing, 1) the foliage is at least double pinnate and fern-like in appearance, 2) the foliage has a bitter rank odor, especially when it is bruised, 3) the hairless stems have purple spots, 4) there are undivided bracts at the base of the compound umbel and undivided bractlets at the base of the umbellets, and 5) the small leaflets are pinnately cleft or dentate. Other members of the Carrot family lack one or more of these key features.
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文章
Miss Chen
2018年08月06日
Description: This plant is a summer annual about 1-3' long. It can be erect or sprawl across the ground like a vine. The round stems are smooth and hairless. The hairless alternate leaves are up to 5" long and 2" across. They are ovate, lanceolate-ovate, or slightly cordate. Their margins are smooth and their veins run parallel to each other. The base of each leaf is sessile or clasping, and it has a membranous sheath that wraps around the stem. This sheath is about 1" long and has green longitudinal veins, otherwise it is white or greenish white. The upper edge of the sheath is usually hairless, although it has fine upright hairs for an uncommon variety of this species.
Occasionally, a single flower on a stalk about 1-2" long is produced from the leaf axils. This flower is about ½–1" across, consisting of 2 large blue petals, 1 small white petal, 3 sepals, 5-6 stamens, and a long white style. The sepals are usually pale white and translucent. The upper stamens have showy yellow anthers; they are sterile, but help to attract insects to the flower. The lower stamens are longer than the upper stamens and fertile, although their anthers are less showy. An upturned spathe that lies underneath the flower is green and about 1-2" long. The upper margins of this spathe are free all the way to the base. The blooming period occurs from mid-summer to early fall, and lasts about 1-2 months. Each flower blooms during the morning for a single day, hence the common name. There is no noticeable floral scent. Each flower is replaced by a seed capsule that has 2 cells, each cell containing 2 seeds. These seeds are dark brown or black and have a surface that is bumpy and rough (rugose). The root system is fibrous. This plant can root at the leaf nodes on moist ground, forming new plants vegetatively. At favorable sites, the Asiatic Dayflower forms colonies that can exclude other species of plants.
Cultivation: Partial sun, moist to mesic conditions, and a fertile soil that is loamy or slightly sandy are preferred. This plant also tolerates full sun and light shade. Occasionally, it can spread aggressively and become a pest.
Range & Habitat: The Asiatic Dayflower is a common plant that occurs in most counties of Illinois (see Distribution Map). It appears to be spreading into all areas of the state. Habitats include edges of floodplain forests, thickets, edges of gardens and yards, areas along buildings, fence rows, vacant lots, and waste areas. This plant prefers disturbed areas, although it occasionally invades natural areas. As the common name implies, it was introduced into the United States from East Asia, probably for horticultural purposes.
Faunal Associations: Primarily bees pollinate the flowers. The foliage is eaten by Neolema sexpunctata (Six-Spotted Beetle). Occasionally, the seeds are eaten by upland gamebirds and songbirds, including the Mourning Dove, Bobwhite, and Redwing Blackbird. The foliage of Dayflowers is a preferred food source of the White-Tailed Deer.
Photographic Location: A small colony of Asiatic Dayflower was flourishing between the shrubbery of a commercial bank and a city sidewalk in Urbana, Illinois.
Comments: The flowers of this species have a "true blue" color that is found in few other plants. Usually, most "blue" flowers are closer to violet or purple. The Asiatic Dayflower has become the most common Commelina sp. (Dayflower) in Illinois for reasons that are not entirely clear. Like the native Commelina erecta (Erect Dayflower), its flowers have a small lower petal that is white, whereas the flowers of other Commelina spp. within the state have a lower petal that is blue or violet. The Erect Dayflower differs from the Asiatic Dayflower in a number of characteristics, including the following: 1) It has more narrow leaves than the latter; 2) The upper margins of each upturned spathe are united together about 1/3 the length of the spathe from the base, rather than running free from each other; 3) Each seed capsule has 3 cells containing 1 seed each, rather than 2 cells containing 2 seeds each; 4) It is a more erect plant than the latter; and 5) Its seeds are lighter-colored with a smooth surface, rather than dark and rugose.
Occasionally, a single flower on a stalk about 1-2" long is produced from the leaf axils. This flower is about ½–1" across, consisting of 2 large blue petals, 1 small white petal, 3 sepals, 5-6 stamens, and a long white style. The sepals are usually pale white and translucent. The upper stamens have showy yellow anthers; they are sterile, but help to attract insects to the flower. The lower stamens are longer than the upper stamens and fertile, although their anthers are less showy. An upturned spathe that lies underneath the flower is green and about 1-2" long. The upper margins of this spathe are free all the way to the base. The blooming period occurs from mid-summer to early fall, and lasts about 1-2 months. Each flower blooms during the morning for a single day, hence the common name. There is no noticeable floral scent. Each flower is replaced by a seed capsule that has 2 cells, each cell containing 2 seeds. These seeds are dark brown or black and have a surface that is bumpy and rough (rugose). The root system is fibrous. This plant can root at the leaf nodes on moist ground, forming new plants vegetatively. At favorable sites, the Asiatic Dayflower forms colonies that can exclude other species of plants.
Cultivation: Partial sun, moist to mesic conditions, and a fertile soil that is loamy or slightly sandy are preferred. This plant also tolerates full sun and light shade. Occasionally, it can spread aggressively and become a pest.
Range & Habitat: The Asiatic Dayflower is a common plant that occurs in most counties of Illinois (see Distribution Map). It appears to be spreading into all areas of the state. Habitats include edges of floodplain forests, thickets, edges of gardens and yards, areas along buildings, fence rows, vacant lots, and waste areas. This plant prefers disturbed areas, although it occasionally invades natural areas. As the common name implies, it was introduced into the United States from East Asia, probably for horticultural purposes.
Faunal Associations: Primarily bees pollinate the flowers. The foliage is eaten by Neolema sexpunctata (Six-Spotted Beetle). Occasionally, the seeds are eaten by upland gamebirds and songbirds, including the Mourning Dove, Bobwhite, and Redwing Blackbird. The foliage of Dayflowers is a preferred food source of the White-Tailed Deer.
Photographic Location: A small colony of Asiatic Dayflower was flourishing between the shrubbery of a commercial bank and a city sidewalk in Urbana, Illinois.
Comments: The flowers of this species have a "true blue" color that is found in few other plants. Usually, most "blue" flowers are closer to violet or purple. The Asiatic Dayflower has become the most common Commelina sp. (Dayflower) in Illinois for reasons that are not entirely clear. Like the native Commelina erecta (Erect Dayflower), its flowers have a small lower petal that is white, whereas the flowers of other Commelina spp. within the state have a lower petal that is blue or violet. The Erect Dayflower differs from the Asiatic Dayflower in a number of characteristics, including the following: 1) It has more narrow leaves than the latter; 2) The upper margins of each upturned spathe are united together about 1/3 the length of the spathe from the base, rather than running free from each other; 3) Each seed capsule has 3 cells containing 1 seed each, rather than 2 cells containing 2 seeds each; 4) It is a more erect plant than the latter; and 5) Its seeds are lighter-colored with a smooth surface, rather than dark and rugose.
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文章
Miss Chen
2018年08月03日
Description: This plant is a summer annual about 3-5' tall. It often branches toward the base of the plant, while the upper stems remain unbranched. These stems are light green and covered with long glandular hairs. The lower to middle leaves are palmately compound with 3-7 leaflets, while the upper leaves are simple. These leaves are alternate and become smaller in size as they ascend the stems. The compound leaves span up to 6-8" across; the lower compound leaves have long stout petioles, while the upper compound leaves have short stout petioles or they are sessile. These petioles are light green and covered with glandular hairs. At the base of each petiole, there is a pair of small spiny stipules. The leaflets of the compound leaves are narrowly ovate, oblanceolate, or lanceolate in shape, and their margins are smooth or serrated. Both sides of these leaflets are covered with short glandular hairs; their upper surfaces are medium to dark green. The simple leaves are broadly lanceolate to cordate-ovate, sessile to clasping along each upper stem, and smaller in size than the compound leaves; otherwise they have similar characteristics. The glandular hairs of the foliage provide the plant with a fetid scent.
The upper stems terminate in large racemes of flowers. These flowers are crowded together toward the apex of each raceme, while scattered seedpods develop below. Each flower spans about 1–1½" across (excluding the stamens), consisting of 4 white to pink petals, 4 light green sepals, 6 long-exerted stamens, and a pistil with a short style. The erect to ascending petals are oblanceolate with well-rounded margins, becoming linear (or clawed) near the base of the flower. The stamens have long slender filaments about 2-3" long. The sepals are linear-lanceolate and much smaller than the petals; they bend away from the base of the flower with age. Each flower has an ascending pedicel. The blooming period occurs from mid-summer to early fall and lasts 1½–3 months. Each flower is replaced by a cylindrical seedpod on a long narrow stipe. Both the seedpod and the stipe are glabrous. Each seedpod contains several seeds. The root system consists of a taproot. This plant spreads by reseeding itself.
Cultivation: Spider Flower adapts to full or partial sun, moist to slightly dry conditions, and different kinds of soil, including those containing loam, clay-loam, or gravel. It requires warm weather and a long growing season to fully develop from seed.
Range & Habitat: Spider Flower has naturalized in Illinois in widely scattered areas (see Distribution Map). Aside from its cultivation in gardens, this species is uncommon and rarely persists. It was introduced into North America from tropical South America as an ornamental plant. Habitats include vacant lots, edges of yards, gravelly shores along rivers, and miscellaneous waste areas. It is usually found in habitats with a history of disturbance.
Faunal Associations: In its native tropical habitat, the pollinators of the flowers are primarily bats (Machado et al., 2006), which seek nectar. Sphingid moths also visit the flowers, but they are regarded as nectar thieves. In Illinois and other temperate areas, the pollinators of the flowers are currently unknown. Various beetles appear to be attracted to the flowers, and flies or small bees probably seek nectar or pollen from them. However, the mouthparts and body size of these insects are too small to function as effective pollinators. Other insects that are attracted to Spider Flower and other Cleome spp. include Phyllotreta cruciferae (Crucifer Flea Beetle) and Phyllotreta striolata (Striped Flea Beetle), which chew small holes in the leaves. On rare occasions, the caterpillars of Pieris rapae (Cabbage Butterfly) have been observed to feed on the foliage. According to some observations in western United States, the Ring-Necked Pheasant and Mourning Dove eat the seeds of Cleome spp. to a limited extent. The fetid foliage is rejected by cattle when there is more palatable food available.
Photographic Location: A vacant lot in Urbana, Illinois, where a few plants were growing wild.
Comments: The showy flowers have an odd structure and appearance, although this is not unusual for Cleome spp. (Bee Plants, etc.) and the related Polanisia spp. (Clammyweed). Among the species in this group that naturalize in Illinois, Spider Flower has showier flowers than most and the filaments of its stamens are exceptionally long (2-3" in length). It is also larger in size than these other species (up to 5' tall). The closely related Cleome serrulata (Rocky Mountain Bee Plant) is occasionally adventive from the Western states. It has compound leaves with only 3 leaflets, while the compound leaves of Spider Flower usually have 5-7 leaflets. Species of Clammyweed are distinguished from Cleome spp. primarily by their seedpods, which lack stipes (a beak-like structure in front of the seedpod). An older scientific name for Spider Flower is Cleome spinosa, which refers to the spiny stipules.
The upper stems terminate in large racemes of flowers. These flowers are crowded together toward the apex of each raceme, while scattered seedpods develop below. Each flower spans about 1–1½" across (excluding the stamens), consisting of 4 white to pink petals, 4 light green sepals, 6 long-exerted stamens, and a pistil with a short style. The erect to ascending petals are oblanceolate with well-rounded margins, becoming linear (or clawed) near the base of the flower. The stamens have long slender filaments about 2-3" long. The sepals are linear-lanceolate and much smaller than the petals; they bend away from the base of the flower with age. Each flower has an ascending pedicel. The blooming period occurs from mid-summer to early fall and lasts 1½–3 months. Each flower is replaced by a cylindrical seedpod on a long narrow stipe. Both the seedpod and the stipe are glabrous. Each seedpod contains several seeds. The root system consists of a taproot. This plant spreads by reseeding itself.
Cultivation: Spider Flower adapts to full or partial sun, moist to slightly dry conditions, and different kinds of soil, including those containing loam, clay-loam, or gravel. It requires warm weather and a long growing season to fully develop from seed.
Range & Habitat: Spider Flower has naturalized in Illinois in widely scattered areas (see Distribution Map). Aside from its cultivation in gardens, this species is uncommon and rarely persists. It was introduced into North America from tropical South America as an ornamental plant. Habitats include vacant lots, edges of yards, gravelly shores along rivers, and miscellaneous waste areas. It is usually found in habitats with a history of disturbance.
Faunal Associations: In its native tropical habitat, the pollinators of the flowers are primarily bats (Machado et al., 2006), which seek nectar. Sphingid moths also visit the flowers, but they are regarded as nectar thieves. In Illinois and other temperate areas, the pollinators of the flowers are currently unknown. Various beetles appear to be attracted to the flowers, and flies or small bees probably seek nectar or pollen from them. However, the mouthparts and body size of these insects are too small to function as effective pollinators. Other insects that are attracted to Spider Flower and other Cleome spp. include Phyllotreta cruciferae (Crucifer Flea Beetle) and Phyllotreta striolata (Striped Flea Beetle), which chew small holes in the leaves. On rare occasions, the caterpillars of Pieris rapae (Cabbage Butterfly) have been observed to feed on the foliage. According to some observations in western United States, the Ring-Necked Pheasant and Mourning Dove eat the seeds of Cleome spp. to a limited extent. The fetid foliage is rejected by cattle when there is more palatable food available.
Photographic Location: A vacant lot in Urbana, Illinois, where a few plants were growing wild.
Comments: The showy flowers have an odd structure and appearance, although this is not unusual for Cleome spp. (Bee Plants, etc.) and the related Polanisia spp. (Clammyweed). Among the species in this group that naturalize in Illinois, Spider Flower has showier flowers than most and the filaments of its stamens are exceptionally long (2-3" in length). It is also larger in size than these other species (up to 5' tall). The closely related Cleome serrulata (Rocky Mountain Bee Plant) is occasionally adventive from the Western states. It has compound leaves with only 3 leaflets, while the compound leaves of Spider Flower usually have 5-7 leaflets. Species of Clammyweed are distinguished from Cleome spp. primarily by their seedpods, which lack stipes (a beak-like structure in front of the seedpod). An older scientific name for Spider Flower is Cleome spinosa, which refers to the spiny stipules.
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文章
Miss Chen
2018年08月03日
Description: This perennial vine is semi-woody and up to 30' long. Young stems are green, glabrous, and terete, while older stems are brownish green to brown. Opposite pairs of compound leaves occur at intervals along the stems. These compound leaves are odd-pinnate and they usually have 5 leaflets. The long petioles of these compound leaves can lean or bend around neighboring objects for support; tendrils are not present. This vine can climb small trees, fences, and similar objects; in more open areas, it sprawls across the ground. The leaflets are up to 3" long and 1½" across; they are ovate or ovate-cordate, glabrous, and smooth along their margins. The upper surface of each leaflet is medium green, while the lower surface is dull light green; its major veins are parallel. Each leaflet has a petiolule (or small stalk) at its base of varying length.
From the axils of the upper leaves, there develops flat-headed panicles of flowers. The flowers are usually bisexual, although monoecious vines (with separate male and female flowers) may occur. Each bisexual flower has 4 petal-like white sepals (less often 5), many long stamens, and 5-6 pistils with elongated styles toward the center. Both the stamens and styles of the pistils are white or cream-colored. True petals are absent. The branches and branchlets of the panicle are green and slender. The blooming period occurs from late summer into fall, typically lasting about 1½ months. The flowers have a strong sweet fragrance. After the blooming period, each flower is replaced by a cluster of achenes with long spreading styles. These persistent styles are covered with long white hairs, which provides them with a feathery appearance. The large achenes are ovoid and flattened in shape; they are thinly covered with appressed silky hairs. Because of their feathery styles, the achenes are distributed to some extent by the wind. This perennial vine reproduces by reseeding itself.
Cultivation: Autumn Clematis thrives in full sun to light shade, moist to slightly dry conditions, and a loam or clay-loam soil. It also tolerates gravelly soil and probably sandy soil as well. This vine can smother small shrubs and is rather aggressive; sometimes it even climbs up the trunk of trees to occupy the lower branches.
Range & Habitat: Autumn Clematis has naturalized in widely scattered locations across Illinois (see Distribution Map). This vine is undoubtedly more common than official records indicate, and its abundance within the natural areas of the state is still growing. Habitats include edges of woodlands, thickets, fence rows, areas along railroads and roads, and waste land. Autumn Clematis is native to East Asia and it is often cultivated as an ornamental plant. This species can be considered somewhat invasive.
Faunal Associations: The caterpillars of the moths Horisme intestinata (Brown Bark Carpet), Thyris maculata (Spotted Thyris), and Thyris sepulchralis (Mournful Thyris) feed on the foliage of Clematis spp. The caterpillars of the latter two species are leaf-rollers. There is a lack of information about floral insect visitors for Autumn Clematis, but they are probably similar to the visitors of the native Clematis virginiana (Virgin's Bower). The insect visitors of this latter species include Halictid bees, various kinds of wasps, and an abundance of flies. Most of these insects are seeking nectar from the flowers, although some of them may feed on the pollen or collect it. Because the foliage of Autumn Clematis is toxic, it is not eaten by mammalian herbivores.
Photographic Location: Meadowbrook Park in Urbana, Illinois.
Comments: Like the native Clematis virginiana (Virgin's Bower), Autumn Clematis has showy white flowers. The latter is often found in drier habitats than the former and it blooms later in the year. These two species of Clematis are easy to distinguish: Virgin's Bower has leaflets that are shallowly cleft and dentate, while the leaflet margins of Autumn Clematis are smooth (or nearly so). During the late summer or fall, when the achenes develop, it is also possible to distinguish these species according to their styles: Autumn Clematis has feathery styles, while the styles of Virgin's Bower are more smooth. Other Clematis spp. that occur in natural areas of Illinois have nodding purplish flowers with a very different appearance; they are called 'Leather Flower' vines. Because the leaflets of some Leather Flower vines have smooth margins, it is possible to confuse these species with Autumn Clematis when the flowers are not in bloom. Another scientific name of Autumn Clematis is Clematis dioscoreifolia.
From the axils of the upper leaves, there develops flat-headed panicles of flowers. The flowers are usually bisexual, although monoecious vines (with separate male and female flowers) may occur. Each bisexual flower has 4 petal-like white sepals (less often 5), many long stamens, and 5-6 pistils with elongated styles toward the center. Both the stamens and styles of the pistils are white or cream-colored. True petals are absent. The branches and branchlets of the panicle are green and slender. The blooming period occurs from late summer into fall, typically lasting about 1½ months. The flowers have a strong sweet fragrance. After the blooming period, each flower is replaced by a cluster of achenes with long spreading styles. These persistent styles are covered with long white hairs, which provides them with a feathery appearance. The large achenes are ovoid and flattened in shape; they are thinly covered with appressed silky hairs. Because of their feathery styles, the achenes are distributed to some extent by the wind. This perennial vine reproduces by reseeding itself.
Cultivation: Autumn Clematis thrives in full sun to light shade, moist to slightly dry conditions, and a loam or clay-loam soil. It also tolerates gravelly soil and probably sandy soil as well. This vine can smother small shrubs and is rather aggressive; sometimes it even climbs up the trunk of trees to occupy the lower branches.
Range & Habitat: Autumn Clematis has naturalized in widely scattered locations across Illinois (see Distribution Map). This vine is undoubtedly more common than official records indicate, and its abundance within the natural areas of the state is still growing. Habitats include edges of woodlands, thickets, fence rows, areas along railroads and roads, and waste land. Autumn Clematis is native to East Asia and it is often cultivated as an ornamental plant. This species can be considered somewhat invasive.
Faunal Associations: The caterpillars of the moths Horisme intestinata (Brown Bark Carpet), Thyris maculata (Spotted Thyris), and Thyris sepulchralis (Mournful Thyris) feed on the foliage of Clematis spp. The caterpillars of the latter two species are leaf-rollers. There is a lack of information about floral insect visitors for Autumn Clematis, but they are probably similar to the visitors of the native Clematis virginiana (Virgin's Bower). The insect visitors of this latter species include Halictid bees, various kinds of wasps, and an abundance of flies. Most of these insects are seeking nectar from the flowers, although some of them may feed on the pollen or collect it. Because the foliage of Autumn Clematis is toxic, it is not eaten by mammalian herbivores.
Photographic Location: Meadowbrook Park in Urbana, Illinois.
Comments: Like the native Clematis virginiana (Virgin's Bower), Autumn Clematis has showy white flowers. The latter is often found in drier habitats than the former and it blooms later in the year. These two species of Clematis are easy to distinguish: Virgin's Bower has leaflets that are shallowly cleft and dentate, while the leaflet margins of Autumn Clematis are smooth (or nearly so). During the late summer or fall, when the achenes develop, it is also possible to distinguish these species according to their styles: Autumn Clematis has feathery styles, while the styles of Virgin's Bower are more smooth. Other Clematis spp. that occur in natural areas of Illinois have nodding purplish flowers with a very different appearance; they are called 'Leather Flower' vines. Because the leaflets of some Leather Flower vines have smooth margins, it is possible to confuse these species with Autumn Clematis when the flowers are not in bloom. Another scientific name of Autumn Clematis is Clematis dioscoreifolia.
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文章
Miss Chen
2018年08月03日
Description: This plant is an obligatory biennial that forms a rosette of leaves during the first year, and bolts upward during the second year to produce flowers. It forms occasional side stems, but remains erect in stature, reaching 3-6' in height. The stout stems are light green, somewhat angular, and covered with dense white hairs. The alternate leaves are up to 7" long and 2" across. In outline, they are lanceolate in shape, but deeply pinnatifid. The widely spaced lobes narrow into points that are individually armed with a pale yellow spine. Some of the upper leaves near the flowerheads may be lanceolate or linear, but remain unlobed. Across the surface of the leaves, there are short white hairs and scattered small spines. The upper surface is dark green, while the lower surface is light green. At the base of each leaf, there are a pair of narrow wings that are dark green and decurrent against the stem. These wings are extensions of the leaves and arm the stems with spines up to ¼" long.
The upper stems terminate in flowerheads of purplish pink to purple flowers. Each flowerhead is 1½–2" across and contains numerous disk florets, but no ray florets. Each disk floret is long and tubular, but becomes divided into 5 long thread-like lobes. This provides the flowerhead with a showy hair-like appearance. At the base of each flowerhead, are numerous green bracts that taper into stiff points that curl outward and are quite prickly. Among these bracts are cobwebby hairs in the background. The blooming period occurs from mid- to late summer and lasts about 3-4 weeks, after which the florets wither away. They are replaced by achenes with large tufts of white hair. These achenes are long, slender, and slightly ribbed. TheyDistribution Map are dispersed by the wind. The root system consists of a stout taproot that runs deep into the ground. This plants spreads by reseeding itself and occasionally forms colonies.
Cultivation: This thistle usually grows in full sun under moist to dry conditions. It prefers a fertile soil that consists of loam, clay loam, or that is slightly stony. Occasionally the foliage is affected by mildew during the summer or fall. Individual plants can produce a great abundance of seed, which have a high germination and survival rate. Thus, this plant can be quite aggressive. Because the seeds remain viable for only 1-2 years, one control strategy consists of destroying individual plants before they reach the flowering stage. It is possible for a plant to reestablish itself if a portion of the taproot remains in the ground.
Range & Habitat: The Bull Thistle is a common plant that occurs in most counties of Illinois. This thistle is adventive from Eurasia, and it has existed in the United States since the 19th century, if not earlier. Habitats include pastures, abandoned fields, fence rows, areas along roadsides and railroads, cut-over woods, and miscellaneous waste areas. This species prefers disturbed areas and it is not common in high quality natural areas.
Faunal Associations: The nectar and pollen of the flowers attract many kinds of long-tongued bees, including bumblebees, leaf-cutting bees (Megachile spp.), long-horned bees (Melissodes spp.), and cuckoo bees (Epeolus spp.). The flower nectar also attracts butterflies (especially swallowtails), skippers, and bee flies. Green metallic bees and other Halictid bees may collect pollen from the flowers, but they are non-pollinating. The caterpillars of the butterfly Vanessa cardui (Painted Lady) feed on the foliage. There are also many moth species with caterpillars that consume various parts of thistles (see Moth Table). The seeds are eaten by the American Goldfinch and the Clay-colored Sparrow. Goldfinches also use the tufts of hair as construction material for their little nests. Mammalian herbivores don't eat the Bull Thistle because it is heavily armed with spines. Even in overgrazed pastures where cattle and sheep have little to eat, the Bull Thistle is one of the few plants that is left alone.
Photographic Location: Along a fence row near the webmaster's apartment in Urbana, Illinois.
Comments: This is a very spiny thistle that can become quite tall. It is easily distinguished from many of the native thistles by the prickly bracts at the base of the flowerheads. These large bracts curl outward and narrow into sharp points, while the bracts of native thistles are appressed together and resemble green fish scales (fine spines are usually present on the outer bracts for some native species). The leaf undersides of the Bull Thistle are light green or whitish green, while the leaf undersides for some native thistles, such as Cirsium discolor (Pasture Thistle) and Cirsium altissimum (Tall Thistle), are powdery white in appearance. Other native thistles, however, don't have this latter characteristic. The Bull Thistle also has spines on its stems (from the decurrent extensions of the leaves), while the stems of native thistles are spineless.
The upper stems terminate in flowerheads of purplish pink to purple flowers. Each flowerhead is 1½–2" across and contains numerous disk florets, but no ray florets. Each disk floret is long and tubular, but becomes divided into 5 long thread-like lobes. This provides the flowerhead with a showy hair-like appearance. At the base of each flowerhead, are numerous green bracts that taper into stiff points that curl outward and are quite prickly. Among these bracts are cobwebby hairs in the background. The blooming period occurs from mid- to late summer and lasts about 3-4 weeks, after which the florets wither away. They are replaced by achenes with large tufts of white hair. These achenes are long, slender, and slightly ribbed. TheyDistribution Map are dispersed by the wind. The root system consists of a stout taproot that runs deep into the ground. This plants spreads by reseeding itself and occasionally forms colonies.
Cultivation: This thistle usually grows in full sun under moist to dry conditions. It prefers a fertile soil that consists of loam, clay loam, or that is slightly stony. Occasionally the foliage is affected by mildew during the summer or fall. Individual plants can produce a great abundance of seed, which have a high germination and survival rate. Thus, this plant can be quite aggressive. Because the seeds remain viable for only 1-2 years, one control strategy consists of destroying individual plants before they reach the flowering stage. It is possible for a plant to reestablish itself if a portion of the taproot remains in the ground.
Range & Habitat: The Bull Thistle is a common plant that occurs in most counties of Illinois. This thistle is adventive from Eurasia, and it has existed in the United States since the 19th century, if not earlier. Habitats include pastures, abandoned fields, fence rows, areas along roadsides and railroads, cut-over woods, and miscellaneous waste areas. This species prefers disturbed areas and it is not common in high quality natural areas.
Faunal Associations: The nectar and pollen of the flowers attract many kinds of long-tongued bees, including bumblebees, leaf-cutting bees (Megachile spp.), long-horned bees (Melissodes spp.), and cuckoo bees (Epeolus spp.). The flower nectar also attracts butterflies (especially swallowtails), skippers, and bee flies. Green metallic bees and other Halictid bees may collect pollen from the flowers, but they are non-pollinating. The caterpillars of the butterfly Vanessa cardui (Painted Lady) feed on the foliage. There are also many moth species with caterpillars that consume various parts of thistles (see Moth Table). The seeds are eaten by the American Goldfinch and the Clay-colored Sparrow. Goldfinches also use the tufts of hair as construction material for their little nests. Mammalian herbivores don't eat the Bull Thistle because it is heavily armed with spines. Even in overgrazed pastures where cattle and sheep have little to eat, the Bull Thistle is one of the few plants that is left alone.
Photographic Location: Along a fence row near the webmaster's apartment in Urbana, Illinois.
Comments: This is a very spiny thistle that can become quite tall. It is easily distinguished from many of the native thistles by the prickly bracts at the base of the flowerheads. These large bracts curl outward and narrow into sharp points, while the bracts of native thistles are appressed together and resemble green fish scales (fine spines are usually present on the outer bracts for some native species). The leaf undersides of the Bull Thistle are light green or whitish green, while the leaf undersides for some native thistles, such as Cirsium discolor (Pasture Thistle) and Cirsium altissimum (Tall Thistle), are powdery white in appearance. Other native thistles, however, don't have this latter characteristic. The Bull Thistle also has spines on its stems (from the decurrent extensions of the leaves), while the stems of native thistles are spineless.
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Miss Chen
2018年08月03日
Description: This annual or biennial plant is usually 1½–3' high, branching occasionally. The stems are variously colored, ranging from green to reddish brown. The lower stems can be quite hairy, while the upper stems are nearly hairless. The alternate leaves are up to 8" long and 2" across, becoming smaller as they ascend the stems. They are lanceolate, elliptic, or oblanceolate in overall shape, and either pinnatifid or dentate; the upper leaves have margins that are more smooth (entire). Each leaf narrows gradually to a petiole-like base, where it is either sessile or clasps the stem. There are usually conspicuous hairs along the central vein of the lower leaf surface.
The upper stems terminate in long inflorescences that are either spike-like, or they are open branching panicles. Widely spaced along the flowering stalks, there are sessile or nearly sessile flowerheads and short triangular bracts. These flowerheads are about 1-1½" across and they have 10-20 ray florets. The petaloid rays of these florets are light blue, fading to white; there are 5 tiny teeth at the tip of each petaloid ray. Toward the center of each flowerhead, there are several light blue stamens with blue anthers. The flowerheads bloom during the morning, and close-up later in the day, unless the skies are cloudy. The blooming period can occur from early summer to early fall, depending on the weather and the timing of disturbances (such as occasional mowing). The achenes are oblongoid and 5-ribbed; there is a pair of small scales at the apex of each achene. The root system consists of a stout taproot. Common Chicory spreads by reseeding itself.
Cultivation: Common Chicory appears to prefer full sun and a heavy soil that contains clay or gravel. This plant is typically found in locations that are mesic to dry, and it withstands drought rather well. Road salt and alkaline conditions are tolerated better than most plants. The foliage can appear rather battered-looking by the end of a hot dry summer.
Range & Habitat: The non-native Common Chicory has been reported in nearly all areas of Illinois, except a few counties in the NW and SE sections of the state (see Distribution Map). It is quite possible that Common Chicory occurs in those counties as well. This plant originated from Eurasia, and was present in Illinois by the late 19th century. It has been spreading steadily ever since and has become common, particularly in disturbed open areas. Typical habitats include pastures, abandoned fields, areas along roadsides and railroads, grassy areas that are not mowed regularly, undeveloped real estate lots, and other waste areas. Occasionally, Common Chicory colonizes disturbed areas of natural habitats (e.g., early stages of a prairie restoration), but it is not a serious invader of such natural areas in the long run.
Faunal Associations: The flowers attract short-tongued bees and probably other insects. Both nectar and pollen are available as floral rewards. The foliage of Common Chicory is eaten by Melanoplus bivittatus (Two-Striped Grasshopper), Melanoplus femurrubrum (Red-Legged Grasshopper), and probably other grasshoppers. The larvae of a lizard beetle, Acropteroxys gracilis, bore through the stems of this plant, while the caterpillars of the moth, Pyrrhia exprimens (Purple-Lined Sallow), feed on the the flowers, buds, and developing achenes. Because the foliage contains a bitter white latex, it is probably not preferred as a food source by mammalian herbivores, although cattle and sheep reportedly eat the basal leaves.
Photographic Location: Along a roadside in Urbana, Illinois.
Comments: The roots of Common Chicory have been roasted to create a coffee-substitute; they are also used as an ingredient in some herbal teas. The flowerheads are very beautiful, but short-lived. This species is easy to identify because of the appearance of these flowerheads – they are a lovely light blue, whereas similar plants in the Aster family usually have yellow flowerheads. However, some Lactuca spp. (Wild Lettuce) have light blue flowerheads that are smaller in size. These latter species produce achenes with tufts of hair, whereas the achenes of Common Chicory have only small scales.
The upper stems terminate in long inflorescences that are either spike-like, or they are open branching panicles. Widely spaced along the flowering stalks, there are sessile or nearly sessile flowerheads and short triangular bracts. These flowerheads are about 1-1½" across and they have 10-20 ray florets. The petaloid rays of these florets are light blue, fading to white; there are 5 tiny teeth at the tip of each petaloid ray. Toward the center of each flowerhead, there are several light blue stamens with blue anthers. The flowerheads bloom during the morning, and close-up later in the day, unless the skies are cloudy. The blooming period can occur from early summer to early fall, depending on the weather and the timing of disturbances (such as occasional mowing). The achenes are oblongoid and 5-ribbed; there is a pair of small scales at the apex of each achene. The root system consists of a stout taproot. Common Chicory spreads by reseeding itself.
Cultivation: Common Chicory appears to prefer full sun and a heavy soil that contains clay or gravel. This plant is typically found in locations that are mesic to dry, and it withstands drought rather well. Road salt and alkaline conditions are tolerated better than most plants. The foliage can appear rather battered-looking by the end of a hot dry summer.
Range & Habitat: The non-native Common Chicory has been reported in nearly all areas of Illinois, except a few counties in the NW and SE sections of the state (see Distribution Map). It is quite possible that Common Chicory occurs in those counties as well. This plant originated from Eurasia, and was present in Illinois by the late 19th century. It has been spreading steadily ever since and has become common, particularly in disturbed open areas. Typical habitats include pastures, abandoned fields, areas along roadsides and railroads, grassy areas that are not mowed regularly, undeveloped real estate lots, and other waste areas. Occasionally, Common Chicory colonizes disturbed areas of natural habitats (e.g., early stages of a prairie restoration), but it is not a serious invader of such natural areas in the long run.
Faunal Associations: The flowers attract short-tongued bees and probably other insects. Both nectar and pollen are available as floral rewards. The foliage of Common Chicory is eaten by Melanoplus bivittatus (Two-Striped Grasshopper), Melanoplus femurrubrum (Red-Legged Grasshopper), and probably other grasshoppers. The larvae of a lizard beetle, Acropteroxys gracilis, bore through the stems of this plant, while the caterpillars of the moth, Pyrrhia exprimens (Purple-Lined Sallow), feed on the the flowers, buds, and developing achenes. Because the foliage contains a bitter white latex, it is probably not preferred as a food source by mammalian herbivores, although cattle and sheep reportedly eat the basal leaves.
Photographic Location: Along a roadside in Urbana, Illinois.
Comments: The roots of Common Chicory have been roasted to create a coffee-substitute; they are also used as an ingredient in some herbal teas. The flowerheads are very beautiful, but short-lived. This species is easy to identify because of the appearance of these flowerheads – they are a lovely light blue, whereas similar plants in the Aster family usually have yellow flowerheads. However, some Lactuca spp. (Wild Lettuce) have light blue flowerheads that are smaller in size. These latter species produce achenes with tufts of hair, whereas the achenes of Common Chicory have only small scales.
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Miss Chen
2018年08月03日
Description: This herbaceous plant is a summer annual. A typical plant is about 6" tall and 12" across; it is abundantly branched at the base, and occasionally branched above. The stems are ascending to sprawling, more or less terete, pale reddish green to reddish purple, and glabrous. Sometimes the stems have vertical stripes that are green alternating with red. Alternate leaves occur along the entire length of each stem; they are ¾–2" long and 6-15 mm. across. The leaves are elliptic-oblong, elliptic, broadly elliptic, or lanceolate; they are shallowly pinnatifid, coarsely dentate, and/or sinuate along their margins. The leaf bases are wedge-shaped, while their tips and lobes (if any) are blunt or acute. The upper leaf surface is medium green or bluish green and glabrous, while the lower leaf surface is white-mealy (farinose). The petioles are up to ½" long, light green to yellowish red, and glabrous. The stems eventually terminate in either spikes or panicles of interrupted clusters of flowers; there are also axillary spikes of flowers that develop from the upper leaves. Individual floral spikes are up to 2" long; there are several small flowers per cluster. Some flowers may have pedicels up to 0.5 mm. long. Each mature flower is about 2 mm. across, consisting of 3-5 greenish sepals, 3-5 stamens, and a pistil with a pair of styles; there are no petals. The sepals are lanceolate to ovate, bluntly tipped, and glabrous; they are either weakly keeled or flat. The stamens are exserted with yellow anthers. The rachises of floral spikes are glabrous.
The blooming period occurs from early summer to early autumn. However, individual plants remain in bloom for about 1 month; only a few flowers bloom at the same time. The flowers are cross-pollinated by the wind. Afterwards, the ovaries of the flowers develop into seeds (a single seed per flower); the orientation of these seeds may be vertical or horizontal. The persistent sepals cover only the edges of these seeds. Individual seeds are 0.5–1 mm. across, globular-flattened in shape, and dark brown to dark reddish brown. Thin membranes cover the seeds; they are easily removed. The root system consists of a shallow taproot with secondary roots that are fibrous. This plant reproduces by reseeding itself.
Cultivation: The preference is full to partial sun, more or less mesic conditions, and soil containing some sand or loose loam. The size of individual plants is variable, depending on soil fertility and moisture conditions. Once the seeds have germinated in late spring, growth and development is rapid.
Range & Habitat: The adventive Oak-leaved Goosefoot is occasional in NE Illinois and uncommon elsewhere in the state (see Distribution Map). This plant is native to Eurasia. Habitats include cropland, gardens, construction sites, areas along railroads, roadsides, barnyards, and waste areas. Habitats with a history of disturbance are preferred, especially when this exposes the topsoil.
Faunal Associations: Various insects feed on the foliage, roots, and other parts of goosefoot species (Chenopodium spp.). These insect feeders include the Three-spotted Flea Beetle (Disonycha triangularis), larvae of the Spinach Leafminer Fly (Pegomya hyoscyami), the Chenopodium Aphid (Hayhurstia atriplicis) and Sugar Beet Root Aphid (Pemphigus betae), the Chenopodium Leafhopper (Norvellina chenopodii), and the larvae of such moths as the Flamboyant Twirler Moth (Chrysoesthia lingulacella), Hollow-spotted Blepharomastix (Blepharomastix ranalis), Chenopodium Scythris Moth (Scythris limbella), Eight-Spot (Amyna octo), Ragweed Borer Moth (Epiblema strenuana), and Morning Glory Plume Moth (Emmelina monodactyla). In addition, the caterpillars of two skippers, the Common Sootywing (Pholisora catullus) and Hayhurst's Scallopwing (Staphylus hayhurstii), also feed on these plants. Among vertebrate animals, upland gamebirds and many songbirds, especially sparrows, eat the seeds of goosefoot species (Martin et al., 1951/1961). The Bird Table provides a list of these species. Some small rodents also eat the seeds, including the Thirteen-lined Ground Squirrel, Prairie Deer Mouse, and White-footed Mouse (Whitaker, 1966). White-tailed Deer browse on the foliage and seedheads of goosefoot species, including Oak-leaved Goosefoot. The seeds of these plants are able to pass through the digestive tract of this animal and remain viable. In this manner, the seeds are dispersed across considerable distances (Myers et al., 2004).
Photographic Location: Along a sidewalk in Urbana, Illinois, where some construction and landscaping activity occurred.
Comments: Oak-leaved Goosefoot (Chenopodium glaucum) can be distinguished from most goosefoot species (Chenopodium spp.) by the shape of its leaves. In addition, the undersides of its leaves are white-mealy, while the rest of the plant is glabrous or nearly so. The flowers of Oak-leaved Goosefoot are also glabrous, and their sepals cover only the margins of the developing ovaries or seeds. Other goosefoot species usually have differently shaped leaves, their flowers are more or less white-mealy, and their sepals cover most of the developing ovaries or seeds. Like other weedy goosefoot species, Oak-leaved Goosefoot has a preference for disturbed habitats with exposed topsoil. It is less erect than most of them, having a tendency to remain relatively low and sprawl across the ground. There is a variety of Oak-leaved Goosefoot, Chenopodium glaucum salinum, that is native to the western United States. It tends to have bluish foliage, while the lobes, teeth, and tips of its leaves are usually more narrow and pointed. There are no records of this variety occurring in Illinois at the present time.
The blooming period occurs from early summer to early autumn. However, individual plants remain in bloom for about 1 month; only a few flowers bloom at the same time. The flowers are cross-pollinated by the wind. Afterwards, the ovaries of the flowers develop into seeds (a single seed per flower); the orientation of these seeds may be vertical or horizontal. The persistent sepals cover only the edges of these seeds. Individual seeds are 0.5–1 mm. across, globular-flattened in shape, and dark brown to dark reddish brown. Thin membranes cover the seeds; they are easily removed. The root system consists of a shallow taproot with secondary roots that are fibrous. This plant reproduces by reseeding itself.
Cultivation: The preference is full to partial sun, more or less mesic conditions, and soil containing some sand or loose loam. The size of individual plants is variable, depending on soil fertility and moisture conditions. Once the seeds have germinated in late spring, growth and development is rapid.
Range & Habitat: The adventive Oak-leaved Goosefoot is occasional in NE Illinois and uncommon elsewhere in the state (see Distribution Map). This plant is native to Eurasia. Habitats include cropland, gardens, construction sites, areas along railroads, roadsides, barnyards, and waste areas. Habitats with a history of disturbance are preferred, especially when this exposes the topsoil.
Faunal Associations: Various insects feed on the foliage, roots, and other parts of goosefoot species (Chenopodium spp.). These insect feeders include the Three-spotted Flea Beetle (Disonycha triangularis), larvae of the Spinach Leafminer Fly (Pegomya hyoscyami), the Chenopodium Aphid (Hayhurstia atriplicis) and Sugar Beet Root Aphid (Pemphigus betae), the Chenopodium Leafhopper (Norvellina chenopodii), and the larvae of such moths as the Flamboyant Twirler Moth (Chrysoesthia lingulacella), Hollow-spotted Blepharomastix (Blepharomastix ranalis), Chenopodium Scythris Moth (Scythris limbella), Eight-Spot (Amyna octo), Ragweed Borer Moth (Epiblema strenuana), and Morning Glory Plume Moth (Emmelina monodactyla). In addition, the caterpillars of two skippers, the Common Sootywing (Pholisora catullus) and Hayhurst's Scallopwing (Staphylus hayhurstii), also feed on these plants. Among vertebrate animals, upland gamebirds and many songbirds, especially sparrows, eat the seeds of goosefoot species (Martin et al., 1951/1961). The Bird Table provides a list of these species. Some small rodents also eat the seeds, including the Thirteen-lined Ground Squirrel, Prairie Deer Mouse, and White-footed Mouse (Whitaker, 1966). White-tailed Deer browse on the foliage and seedheads of goosefoot species, including Oak-leaved Goosefoot. The seeds of these plants are able to pass through the digestive tract of this animal and remain viable. In this manner, the seeds are dispersed across considerable distances (Myers et al., 2004).
Photographic Location: Along a sidewalk in Urbana, Illinois, where some construction and landscaping activity occurred.
Comments: Oak-leaved Goosefoot (Chenopodium glaucum) can be distinguished from most goosefoot species (Chenopodium spp.) by the shape of its leaves. In addition, the undersides of its leaves are white-mealy, while the rest of the plant is glabrous or nearly so. The flowers of Oak-leaved Goosefoot are also glabrous, and their sepals cover only the margins of the developing ovaries or seeds. Other goosefoot species usually have differently shaped leaves, their flowers are more or less white-mealy, and their sepals cover most of the developing ovaries or seeds. Like other weedy goosefoot species, Oak-leaved Goosefoot has a preference for disturbed habitats with exposed topsoil. It is less erect than most of them, having a tendency to remain relatively low and sprawl across the ground. There is a variety of Oak-leaved Goosefoot, Chenopodium glaucum salinum, that is native to the western United States. It tends to have bluish foliage, while the lobes, teeth, and tips of its leaves are usually more narrow and pointed. There are no records of this variety occurring in Illinois at the present time.
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Miss Chen
2018年08月01日
Description: This plant is a summer annual about 2-5' tall (in more tropical climates, it is a perennial). More or less erect, Mexican Tea branches occasionally to frequently; Small side branches frequently develop from the axils of the leaves. The stems are terete to slightly angular, hairless, conspicuously veined, and variably colored – often some combination of olive green, dull red, and cream. The alternate leaves are up to 4" long and 1½" across; they are ovate to narrowly ovate, medium green to yellow-green or red-green, and hairless. The bases of these leaves are always wedge-shaped and never rounded. The leaf undersides are never white-mealy. The leaf margins are highly variable, even on the same plant – smooth, undulate, bluntly dentate, or somewhat pinnatifid. The upper leaves are smaller in size than the moderate to lower leaves, and their leaf margins are more smooth. Both the stems and leaves have minute glands that secrete an aromatic oil; they exude a somewhat musky medicinal scent.
The upper stems and smaller side stems terminate in spikes of sessile flowers (up to 1' long) that are interspersed with small leafy bracts. The small greenish flowers are arranged in dense clusters along these spikes. Each flower is a little less than ¼" across, consisting of 5 green sepals, a rather flat pistil with tiny styles, and 5 stamens with large white anthers. The small sepals are ovate in shape and curved inward; they are neither hairy nor white-mealy. The anthers are the most conspicuous part of the flower. The blooming period occurs from mid-summer into the fall and lasts 2-3 months. The bisexual flowers are wind-pollinated, although they can also self-pollinate themselves. Each flower is replaced by a single tiny seed (achene); a thinDistribution Map membrane surrounding the seed is rather loose and easily removed. The seeds are round, flattened, black, and shiny; they are small enough to be blown about by the wind. The root system consists of a taproot.
Cultivation: Mexican Tea prefers full to partial sun and moist to slightly dry conditions. Growth is more robust in fertile loamy soil with abundant nitrogen, but it will adapt to other kinds of soil.
Range & Habitat: The non-native Mexican Tea is occasional in the southern half of Illinois, becoming uncommon or absent in the northern half of the state. It was introduced from tropical America as a medicinal herb. Habitats include fields, roadsides, vacant lots, and waste areas. Mexican Tea is still cultivated in gardens, from where it occasionally escapes and manages to reseed itself. Disturbed habitats of a relatively open character are strongly preferred.
Faunal Associations: Information that is specific to Mexican Tea is lacking (except for grazing mammals), therefore faunal-floral relationships for Chenopodium spp. in general will be presented. I suspect that some insects are deterred by the toxicity of the floral oil, and don't feed on this species to same extent as other Chenopodium spp. The caterpillars of two skippers, Pholisora catullus (Common Sootywing) and Staphylus hayhurstii (Hayhurst's Scallopwing), feed on the leaves of Chenopodium spp. Other insect feeders include moth caterpillars, flea beetles, leaf beetles, plant bugs, and aphids (see the Insect Table for a listing of these species). The tiny seeds are eaten by many small songbirds, particularly sparrows (see the Bird Table); some upland gamebirds (e.g., Bobwhite, Hungarian Partridge, & Ring-Necked Pheasant) also eat the seeds or seedheads. Small rodents eat the seeds, including the Thirteen-Lined Ground Squirrel, White-Footed Mouse, and Prairie Deer Mouse. Because the foliage is toxic and probably distasteful, it is not eaten by grazing mammals; even goats refuse to eat this plant (see Georgia, 1913).
Photographic Location: A garden in downtown Champaign, Illinois.
Comments: Because of its anthelmintic properties, Mexican Tea has been used to remove intestinal worms. This is one of the reasons it is cultivated as a medicinal herb. This plant can be distinguished from other Chenopodium spp. by the shape of its leaves, the absence of white-mealiness on its leaf undersides and sepals, and the strong aroma of its foliage. Its lower to middle leaves have wedge-shaped bottoms, while the leaf bottoms of similar Chenopodium spp. are usually well-rounded. Sometimes the margins of these leaves are more wavy or pinnatifid than those of other species. This combination of factors makes Mexican Tea one of the easier Chenopodium spp. to identify. A variety of Mexican Tea that is without leafy bracts in its floral spikes has been referred to as Chenopodium ambrosioides anthelminticum. It is less common than the typical variety.
The upper stems and smaller side stems terminate in spikes of sessile flowers (up to 1' long) that are interspersed with small leafy bracts. The small greenish flowers are arranged in dense clusters along these spikes. Each flower is a little less than ¼" across, consisting of 5 green sepals, a rather flat pistil with tiny styles, and 5 stamens with large white anthers. The small sepals are ovate in shape and curved inward; they are neither hairy nor white-mealy. The anthers are the most conspicuous part of the flower. The blooming period occurs from mid-summer into the fall and lasts 2-3 months. The bisexual flowers are wind-pollinated, although they can also self-pollinate themselves. Each flower is replaced by a single tiny seed (achene); a thinDistribution Map membrane surrounding the seed is rather loose and easily removed. The seeds are round, flattened, black, and shiny; they are small enough to be blown about by the wind. The root system consists of a taproot.
Cultivation: Mexican Tea prefers full to partial sun and moist to slightly dry conditions. Growth is more robust in fertile loamy soil with abundant nitrogen, but it will adapt to other kinds of soil.
Range & Habitat: The non-native Mexican Tea is occasional in the southern half of Illinois, becoming uncommon or absent in the northern half of the state. It was introduced from tropical America as a medicinal herb. Habitats include fields, roadsides, vacant lots, and waste areas. Mexican Tea is still cultivated in gardens, from where it occasionally escapes and manages to reseed itself. Disturbed habitats of a relatively open character are strongly preferred.
Faunal Associations: Information that is specific to Mexican Tea is lacking (except for grazing mammals), therefore faunal-floral relationships for Chenopodium spp. in general will be presented. I suspect that some insects are deterred by the toxicity of the floral oil, and don't feed on this species to same extent as other Chenopodium spp. The caterpillars of two skippers, Pholisora catullus (Common Sootywing) and Staphylus hayhurstii (Hayhurst's Scallopwing), feed on the leaves of Chenopodium spp. Other insect feeders include moth caterpillars, flea beetles, leaf beetles, plant bugs, and aphids (see the Insect Table for a listing of these species). The tiny seeds are eaten by many small songbirds, particularly sparrows (see the Bird Table); some upland gamebirds (e.g., Bobwhite, Hungarian Partridge, & Ring-Necked Pheasant) also eat the seeds or seedheads. Small rodents eat the seeds, including the Thirteen-Lined Ground Squirrel, White-Footed Mouse, and Prairie Deer Mouse. Because the foliage is toxic and probably distasteful, it is not eaten by grazing mammals; even goats refuse to eat this plant (see Georgia, 1913).
Photographic Location: A garden in downtown Champaign, Illinois.
Comments: Because of its anthelmintic properties, Mexican Tea has been used to remove intestinal worms. This is one of the reasons it is cultivated as a medicinal herb. This plant can be distinguished from other Chenopodium spp. by the shape of its leaves, the absence of white-mealiness on its leaf undersides and sepals, and the strong aroma of its foliage. Its lower to middle leaves have wedge-shaped bottoms, while the leaf bottoms of similar Chenopodium spp. are usually well-rounded. Sometimes the margins of these leaves are more wavy or pinnatifid than those of other species. This combination of factors makes Mexican Tea one of the easier Chenopodium spp. to identify. A variety of Mexican Tea that is without leafy bracts in its floral spikes has been referred to as Chenopodium ambrosioides anthelminticum. It is less common than the typical variety.
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Miss Chen
2018年08月01日
Description: This biennial plant consists of a rosette of basal leaves during the first year. During the second year, this plant becomes about 2' tall; it has branching stems that have a tendency to sprawl. The foliage contains a yellow-orange sap with irritating properties. The rather stout stems are angular, glaucous, and covered with scattered hairs. The alternate compound leaves are up to 6" long and 3" across; they are pinnate-pinnatifid or bipinnatifid and hairless to mostly hairless. Each compound leaf typically has 5 leaflets or lobes that are ovate or obovate in overall shape. These leaflets or lobes are pinnatifid with secondary lobes; they are green and hairless above, and pale green and hairless below with conspicuous veins. Their margins may be coarsely crenate or dentate as well. The secondary lobes have blunt tips. The rachis (if present) and petiole of each compound leaf may have a few scattered hairs. The flowering stalks develop oppositely from the compound leaves. Each stalk is several inches long and it has an umbel of 3-8 flowers at its apex. Each flower is ½–¾" across, consisting of 4 yellow petals, 2 sepals that fall early, a pistil with a stout style, and many yellow stamens. The pedicel of each flower is about ½–1" long.
The blooming period occurs during the summer and lasts about 1-2 months. Each flower is replaced by an ascending seedpod that becomes ¾–2" long. Each seedpod is cylindrical and tapers gradually toward the apex; its outer surface is smooth, glaucous, and hairless. As the seedpod matures, it becomes somewhat constricted at intervals (torulose). The seeds are ovoid, flattened, and shiny; they have small white appendages (elaisomes). This plant reproduces by reseeding itself.
Cultivation: The preference is full sun to light shade, mesic conditions, and a fertile loamy soil.
Range & Habitat: Greater Celandine has naturalized in a few scattered counties in Illinois, where it is uncommon and usually doesn't persist (see Distribution Map). This species was introduced from Europe into North America as an herbal plant and it is still cultivated in gardens. Other habitats include woodlands, roadsides, and waste areas.
Faunal Associations: As a member of the Poppy family (Papaveraceae), the flowers produce pollen only; likely flower visitors include bees and Syrphid flies. Ants are attracted to the seeds because of their elaisomes (food appendages); they carry the seeds off to their nests and help to distribute them. Because the yellow-orange sap of the foliage is toxic, acrid, and bitter-tasting, it seems unlikely that mammalian herbivores feed on this plant. With the possible exception of insects, the value of this plant to wildlife is low.
Photographic Location: An herbal garden at Meadowbrook Park in Urbana, Illinois.
Comments: In the past, the sap of Greater Celandine was used to remove warts and it had other medicinal applications. However, such practices are not recommended because the sap is toxic and extremely irritating to the skin and eyes. Greater Celandine has smaller flowers than other members of the Poppy family in Illinois and its seedpods are more narrow and cylindrical as well. Because its flowers have four petals and its seedpods resemble siliques, this species could be confused with a member of the Mustard family. However, the flowers of Greater Celandine are larger in size than most members of the Mustard family and it has a distinctive yellow-orange sap. Lesser Celandine refers to another European species, Ranunculus ficaria (syn. Ficaria verna), which is a member of the Buttercup family (Ranunculaceae). This latter species has yellow flowers with 8-12 petals and its leaves are orbicular-cordate with crenate margins. Therefore, it is easily distinguished from Greater Celandine.
The blooming period occurs during the summer and lasts about 1-2 months. Each flower is replaced by an ascending seedpod that becomes ¾–2" long. Each seedpod is cylindrical and tapers gradually toward the apex; its outer surface is smooth, glaucous, and hairless. As the seedpod matures, it becomes somewhat constricted at intervals (torulose). The seeds are ovoid, flattened, and shiny; they have small white appendages (elaisomes). This plant reproduces by reseeding itself.
Cultivation: The preference is full sun to light shade, mesic conditions, and a fertile loamy soil.
Range & Habitat: Greater Celandine has naturalized in a few scattered counties in Illinois, where it is uncommon and usually doesn't persist (see Distribution Map). This species was introduced from Europe into North America as an herbal plant and it is still cultivated in gardens. Other habitats include woodlands, roadsides, and waste areas.
Faunal Associations: As a member of the Poppy family (Papaveraceae), the flowers produce pollen only; likely flower visitors include bees and Syrphid flies. Ants are attracted to the seeds because of their elaisomes (food appendages); they carry the seeds off to their nests and help to distribute them. Because the yellow-orange sap of the foliage is toxic, acrid, and bitter-tasting, it seems unlikely that mammalian herbivores feed on this plant. With the possible exception of insects, the value of this plant to wildlife is low.
Photographic Location: An herbal garden at Meadowbrook Park in Urbana, Illinois.
Comments: In the past, the sap of Greater Celandine was used to remove warts and it had other medicinal applications. However, such practices are not recommended because the sap is toxic and extremely irritating to the skin and eyes. Greater Celandine has smaller flowers than other members of the Poppy family in Illinois and its seedpods are more narrow and cylindrical as well. Because its flowers have four petals and its seedpods resemble siliques, this species could be confused with a member of the Mustard family. However, the flowers of Greater Celandine are larger in size than most members of the Mustard family and it has a distinctive yellow-orange sap. Lesser Celandine refers to another European species, Ranunculus ficaria (syn. Ficaria verna), which is a member of the Buttercup family (Ranunculaceae). This latter species has yellow flowers with 8-12 petals and its leaves are orbicular-cordate with crenate margins. Therefore, it is easily distinguished from Greater Celandine.
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Miss Chen
2018年08月01日
Description: This plant is a summer annual forming a mat of branching leafy stems up to 2' across. The stems are light green, pale red, or nearly white; they are terete, hairy, and slightly succulent. The stems are slightly swollen where the stipules of the leaves occur. Pairs of opposite leaves occur at intervals along the stems. Individual leaf blades are 3-11 mm. long and 2-6 mm. across; they are broadly oblong or ovate-oblong in shape and finely toothed along the upper margins. Leaf venation is palmate, although only the central veins are conspicuous. The upper blade surface is dull medium green and hairless to slightly hairy, while the lower surface is pale green to white and hairy. The tips of leaf blades are well-rounded, while their bases are rounded to slightly cordate and often asymmetric. Sometimes the margins of the leaf blades are tinted red. The short petioles are light green to nearly white and usually hairy.
Small clusters of 1-4 inflorescences develop from the axils of each pair of leaves. Each inflorescence is about 2 mm. across, consisting of a cup-like cyathium on a short stalk that contains a single pistillate flower on a short stalk and 4 staminate flowers. Each cyathium is light green and glabrous to slightly hairy; there are 4 red nectar glands with whitish petaloid appendages along the upper rim of each cyathium. The pistillate flower consists of a 3-lobed ovary with a divided style at its apex; the ovary is light green (while immature), ovoid-globoid in shape, and its lobes have spreading hairs. The stalk of the pistillate flower curves sideways or downward initially, but it later becomes erect at maturity. A staminate flower within the inflorescence consists of a single stamen. The blooming period occurs from mid-summer into fall for about 2 months. At maturity, the ovaries develop into 3-celled seed capsules; each cell of a capsule contains a single seed. The seeds are distributed, in part, by mechanical ejection. Individual seeds are about 1.0 mm. in length, oblongoid-rectangular in shape, and transversely ridged. The root system consists of a slender taproot that branches. The foliage of this plant contains a milky latex.
Cultivation: The preference is full to partial sun, dry-mesic to dry conditions, and barren soil containing sand, gravel, or clay. However, Green Creeping Spurge also adapts to soil containing fertile loam if disturbance removes taller ground vegetation. Because of its C4-metabolism and slightly succulent nature, this plant can withstand hot dry conditions.
Range & Habitat: Green Creeping Spurge is a rare plant in Illinois, where it has been accidentally introduced. It has been observed in NE Illinois and more recently in Champaign County (see Distribution Map). These records may underestimate its distribution within the state, however. Green Creeping Spurge is native to tropical America. Habitats include lawns, gardens, areas along railroads and roadsides, areas near parking lots, cracks of urban sidewalks, and barren waste places. Open sunny areas with a history of disturbance are preferred.
Faunal Associations: The nectaries of the flowers attract Syrphid flies, Halictid bees, and various ants (Lasius, Formica, & Forelius spp.). Some bees may also collect pollen. Two aphids suck juices from Chamaesyce spp. (Low Spurges): Macrosiphum euphorbiae and Macrosiphum gei. Other insect feeders include the plant bug, Semium hirtum, and the flea beetle, Glyptina leptosoma. The latter insect feeds on the roots. Because of the toxic white latex and its low stature, mammalian herbivores have little use for Green Creeping Spurge and other Chamaesyce spp. However, the following birds eat the seeds of these plants: Greater Prairie Chicken, Bobwhite, Mourning Dove, Horned Lark, and Chipping Sparrow (Martin et al., 1951/1961). Because of an oily food appendage on each seed (referred to as a 'caruncle'), ants probably play a role in distributing the seeds to new areas.
Photographic Location: Along a parking lot and a railroad in Urbana, Illinois.
Comments: Green Creeping Spurge is a relatively recent invader of Illinois. Because of its low habit and similarity to other Chamaesyce spp. (Low Spurges), this invasion has gone largely unnoticed. At a cursory glance, Green Creeping Spurge resembles a common native species, Prostrate Spurge (Chamaesyce maculata, formerly Chamaesyce supina), and the two species can be found together in the same habitats, particularly in some urban areas. The latter species differs from Green Creeping Spurge as follows: 1) its leaves are about 3 times as long as they are across, rather than 2 times as long as they are across, 2) its leaves often have a patch of dark red in their centers, 3) the lobes of its ovaries/capsules have appressed hairs, rather than spreading hairs, and 4) its mature seed capsules are often found below the leaves on curved stalks, rather than above the leaves on erect stalks. Scientific synonyms of Green Creeping Spurge include Euphorbia prostrata and Euphorbia chamaesyce. Another common name of this species is Prostrate Sandmat.
Small clusters of 1-4 inflorescences develop from the axils of each pair of leaves. Each inflorescence is about 2 mm. across, consisting of a cup-like cyathium on a short stalk that contains a single pistillate flower on a short stalk and 4 staminate flowers. Each cyathium is light green and glabrous to slightly hairy; there are 4 red nectar glands with whitish petaloid appendages along the upper rim of each cyathium. The pistillate flower consists of a 3-lobed ovary with a divided style at its apex; the ovary is light green (while immature), ovoid-globoid in shape, and its lobes have spreading hairs. The stalk of the pistillate flower curves sideways or downward initially, but it later becomes erect at maturity. A staminate flower within the inflorescence consists of a single stamen. The blooming period occurs from mid-summer into fall for about 2 months. At maturity, the ovaries develop into 3-celled seed capsules; each cell of a capsule contains a single seed. The seeds are distributed, in part, by mechanical ejection. Individual seeds are about 1.0 mm. in length, oblongoid-rectangular in shape, and transversely ridged. The root system consists of a slender taproot that branches. The foliage of this plant contains a milky latex.
Cultivation: The preference is full to partial sun, dry-mesic to dry conditions, and barren soil containing sand, gravel, or clay. However, Green Creeping Spurge also adapts to soil containing fertile loam if disturbance removes taller ground vegetation. Because of its C4-metabolism and slightly succulent nature, this plant can withstand hot dry conditions.
Range & Habitat: Green Creeping Spurge is a rare plant in Illinois, where it has been accidentally introduced. It has been observed in NE Illinois and more recently in Champaign County (see Distribution Map). These records may underestimate its distribution within the state, however. Green Creeping Spurge is native to tropical America. Habitats include lawns, gardens, areas along railroads and roadsides, areas near parking lots, cracks of urban sidewalks, and barren waste places. Open sunny areas with a history of disturbance are preferred.
Faunal Associations: The nectaries of the flowers attract Syrphid flies, Halictid bees, and various ants (Lasius, Formica, & Forelius spp.). Some bees may also collect pollen. Two aphids suck juices from Chamaesyce spp. (Low Spurges): Macrosiphum euphorbiae and Macrosiphum gei. Other insect feeders include the plant bug, Semium hirtum, and the flea beetle, Glyptina leptosoma. The latter insect feeds on the roots. Because of the toxic white latex and its low stature, mammalian herbivores have little use for Green Creeping Spurge and other Chamaesyce spp. However, the following birds eat the seeds of these plants: Greater Prairie Chicken, Bobwhite, Mourning Dove, Horned Lark, and Chipping Sparrow (Martin et al., 1951/1961). Because of an oily food appendage on each seed (referred to as a 'caruncle'), ants probably play a role in distributing the seeds to new areas.
Photographic Location: Along a parking lot and a railroad in Urbana, Illinois.
Comments: Green Creeping Spurge is a relatively recent invader of Illinois. Because of its low habit and similarity to other Chamaesyce spp. (Low Spurges), this invasion has gone largely unnoticed. At a cursory glance, Green Creeping Spurge resembles a common native species, Prostrate Spurge (Chamaesyce maculata, formerly Chamaesyce supina), and the two species can be found together in the same habitats, particularly in some urban areas. The latter species differs from Green Creeping Spurge as follows: 1) its leaves are about 3 times as long as they are across, rather than 2 times as long as they are across, 2) its leaves often have a patch of dark red in their centers, 3) the lobes of its ovaries/capsules have appressed hairs, rather than spreading hairs, and 4) its mature seed capsules are often found below the leaves on curved stalks, rather than above the leaves on erect stalks. Scientific synonyms of Green Creeping Spurge include Euphorbia prostrata and Euphorbia chamaesyce. Another common name of this species is Prostrate Sandmat.
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Miss Chen
2018年08月01日
Description: This plant is a summer annual that becomes 3-18" tall; it is low and spreading, but not prostrate. The stems are pinkish red, round, and hairless, except for a few fine hairs on new growth. The opposite leaves are up to 2" long and ¾" across. They are oblong, with short petioles and margins that are smooth or irregularly serrate. The lower surface of each leaf is light green, while the upper surface may have a red blotch in the middle. A few fine hairs may occur near the base of eachStems, Leaves, & Flowers leaf. The inflorescence consists of a small cyathium on a straight pedicel. Usually, several cyathia develop near the ends of each major stem when a plant is mature. A cyathium is a small cup-like structure containing the pistillate flower and one or more staminate flowers, which have neither true petals nor sepals. It is initially green, but often turns red in bright sunlight. On this particular species, the cyathium has 4 tiny petal-like appendages that are bright white. Eventually, a round tripartite fruit develops from the cyathium on a short stalk; it often turns red in bright sunlight as well. This fruit is noticeably larger than the flowers. The blooming period is mid-summer to fall, lasting about 1-2 months. There is no noticeable floral scent. The root system consists of a slender central taproot.
Cultivation: The preference is full sunlight, dry conditions, and poor soil. The soil can contain significant amounts of gravel, sand, or clay. Foliar disease rarely bothers the leaves, and drought resistance is excellent. This plant can reseed itself readily in sunny open areas.
Range & Habitat: The native Nodding Spurge is a common plant that occurs in nearly every county of Illinois (see Distribution Map). Habitats include dry upland areas of prairies, clay prairies, gravel prairies, thickets, openings in upland woodlands, fields and pastures (whether abandoned or still in use), areas along roadsides and railroads, poorly maintained lawns and gardens, and miscellaneous waste areas. This plant prefers disturbed open areas and it is somewhat weedy. This plant seems to be more common in rural than urban areas, possibly because of its intolerance to herbicides and frequent mowing of lawns.
Faunal Associations: The tiny flowers occasionally attract small bees, Syrphid flies, and wasps. These insects seek nectar primarily. The seeds are consumed by the Mourning Dove and Greater Prairie Chicken, and to a lesser extent by the Bobwhite and Horned Lark. The Wild Turkey has been known to eat the foliage, developing buds, and fruits, apparently without ill effects. Mammalian herbivores rarely eat this plant because of the poisonous white latex in the stems and foliage.
Photographic Location: The photographs were taken at the Windsor Road Prairie in Champaign, Illinois. Some flowers are in bloom in one of the photographs as their stamens are clearly visible.
Comments: The Nodding Spurge can be readily distinguished from other Chamaesyce spp. by its more erect habit, larger leaves, and mostly hairless stems. Several scientific names have been applied to the Nodding Spurge in the past, including Chamaesyce maculata, Euphorbia maculata, and Euphorbia preslii. Sometimes the entire plant will turn reddish green in response to strong sunlight and dry conditions.
Cultivation: The preference is full sunlight, dry conditions, and poor soil. The soil can contain significant amounts of gravel, sand, or clay. Foliar disease rarely bothers the leaves, and drought resistance is excellent. This plant can reseed itself readily in sunny open areas.
Range & Habitat: The native Nodding Spurge is a common plant that occurs in nearly every county of Illinois (see Distribution Map). Habitats include dry upland areas of prairies, clay prairies, gravel prairies, thickets, openings in upland woodlands, fields and pastures (whether abandoned or still in use), areas along roadsides and railroads, poorly maintained lawns and gardens, and miscellaneous waste areas. This plant prefers disturbed open areas and it is somewhat weedy. This plant seems to be more common in rural than urban areas, possibly because of its intolerance to herbicides and frequent mowing of lawns.
Faunal Associations: The tiny flowers occasionally attract small bees, Syrphid flies, and wasps. These insects seek nectar primarily. The seeds are consumed by the Mourning Dove and Greater Prairie Chicken, and to a lesser extent by the Bobwhite and Horned Lark. The Wild Turkey has been known to eat the foliage, developing buds, and fruits, apparently without ill effects. Mammalian herbivores rarely eat this plant because of the poisonous white latex in the stems and foliage.
Photographic Location: The photographs were taken at the Windsor Road Prairie in Champaign, Illinois. Some flowers are in bloom in one of the photographs as their stamens are clearly visible.
Comments: The Nodding Spurge can be readily distinguished from other Chamaesyce spp. by its more erect habit, larger leaves, and mostly hairless stems. Several scientific names have been applied to the Nodding Spurge in the past, including Chamaesyce maculata, Euphorbia maculata, and Euphorbia preslii. Sometimes the entire plant will turn reddish green in response to strong sunlight and dry conditions.
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Miss Chen
2018年08月01日
Description: This perennial herbaceous plant consists of a tuft of decumbent leafy stems about 4-12" tall and similarly across. The stems are light green, terete, and more or less covered with short white-woolly hairs; they branch occasionally. Alternate leaves occur along these stems that are ½–2" long and ½–1" across; most of these leaves are located close to the ground where the lower stems sprawl. The leaves are deeply bipinnatifid or tripinnatifid and rather irregular in their branching patterns; their ultimate leaf segments are linear-filiform and short. The leaves are light-medium green and sparsely to moderately covered with very short white-woolly hairs. Solitary flowerheads about ½–1" across are produced from long peduncles up to 6" long. The peduncles are light green, terete, and more or less covered with short white-woolly hairs. Underneath the flowerheads, however, the peduncles become more swollen, slightly furrowed, and more densely covered with white-woolly hairs. Each flowerhead consists of 10-20 ray florets surrounding numerous disk florets; the disk florets are arranged together in a hemispheric head that has a solid interior. The ray florets are pistillate and fertile, while the disk florets are perfect and fertile. The petaloid rays of the flowerheads are white, broadly oblong-elliptic in shape, and widely spreading; their tips have 1-2 small notches.
The corollas of the disk florets are 2-3 mm. long, narrowly tubular in shape, and yellow; they have 5 spreading lobes at their apices. Between the corollas of the disk florets, there are chaffy scales; these scales are white-membranous along their margins and oblong in shape with rounded erose (somewhat frayed) tips. Around the base of each flowerhead, there are phyllaries (floral bracts) in several overlapping and appressed series that together form a shallow saucer-like shape. The phyllaries are lanceolate-oblong with blunt tips, light green with white-membranous margins, and more or less covered with short white-woolly hairs. The blooming period occurs during the summer and early autumn for 1½–3 months. Afterwards, fertile florets are replaced by small achenes about 1–1.5 mm. long. These achenes are oblongoid in shape, pale-colored, and slightly flattened or 3-angled; each achene has 3 filiform ribs on one side. The root system is fibrous, rhizomatous, and relatively shallow. This plant can spread by reseeding itself or by forming clonal offsets from the short rhizomes.
Cultivation: The preference is full or partial sun, moist to mesic conditions, and soil consisting of either loam or sandy loam. This plant is easy to cultivate and it occasionally spreads into adjacent areas.
Range & Habitat: Roman Chamomile has rarely naturalized in Illinois and thus far wild populations have been reported from only a few counties (see Distribution Map). Roman Chamomile is native to western Europe and it was introduced into North America as an ornamental and herbal plant for gardens. In North America, naturalized populations of this plant are found primarily in urban areas, including such habitats as areas near gardens, lawns, grassy roadsides, vacant lots, and construction sites. In Europe, it has been found in such habitats as grassy roadsides, sandy lawns in commons areas, and sandy pastures. Roman Chamomile is still cultivated in flower and herbal gardens, from where it occasionally escapes, but rarely persists. Areas with a history of disturbance are preferred.
Faunal Associations: The nectar and pollen of the flowerheads probably attract small bees and various flies; wasps and beetles may visit the flowerheads to a lesser extent. Two aphids, Macrosiphoniella tanacetaria and Macrosiphoniella tapuskae, are known to feed on Roman Chamomile (Blackman & Eastop, 2013). A polyphagous leafhopper, Empoasca erigeron, also feeds on this plant (Dmitriev & Dietrich, 2010). At the present time, information about this plant's relationships with granivorous birds and herbivorous mammals is unavailable.
Photographic Location: An ornamental garden at the Urbana Public Library of Urbana, Illinois.
Comments: There are several species of plants in the Aster family that have daisy-like flowerheads with white petaloid rays. Many of these species have been introduced into North America from Eurasia as garden plants, including Roman Chamomile (Chamaemelum nobile). Roman Chamomile can be distinguished from most of these species by its highly fragrant foliage and crushed flowerheads, which have an apple-pineapple scent. One other species in this group that has naturalized in Illinois, German Chamomile (Matricaria chamomile), also has foliage and crushed flowerheads with a similar fruity scent. German Chamomile can be readily distinguished by its glabrous foliage, more erect habit, the hollow interior of its flowerheads, and the lack of chaffy scales between the disk florets. This latter plant is also an annual, rather than a perennial. Both of these species have been used as ingredients in Chamomile tea, and the chemical constituents of their flowerheads are said to have relaxing and soothing properties. An alternative scientific name for Roman Chamomile is Anthemis nobilis, and it has other common names, including Low Chamomile, English Chamomile, and Garden Chamomile.
The corollas of the disk florets are 2-3 mm. long, narrowly tubular in shape, and yellow; they have 5 spreading lobes at their apices. Between the corollas of the disk florets, there are chaffy scales; these scales are white-membranous along their margins and oblong in shape with rounded erose (somewhat frayed) tips. Around the base of each flowerhead, there are phyllaries (floral bracts) in several overlapping and appressed series that together form a shallow saucer-like shape. The phyllaries are lanceolate-oblong with blunt tips, light green with white-membranous margins, and more or less covered with short white-woolly hairs. The blooming period occurs during the summer and early autumn for 1½–3 months. Afterwards, fertile florets are replaced by small achenes about 1–1.5 mm. long. These achenes are oblongoid in shape, pale-colored, and slightly flattened or 3-angled; each achene has 3 filiform ribs on one side. The root system is fibrous, rhizomatous, and relatively shallow. This plant can spread by reseeding itself or by forming clonal offsets from the short rhizomes.
Cultivation: The preference is full or partial sun, moist to mesic conditions, and soil consisting of either loam or sandy loam. This plant is easy to cultivate and it occasionally spreads into adjacent areas.
Range & Habitat: Roman Chamomile has rarely naturalized in Illinois and thus far wild populations have been reported from only a few counties (see Distribution Map). Roman Chamomile is native to western Europe and it was introduced into North America as an ornamental and herbal plant for gardens. In North America, naturalized populations of this plant are found primarily in urban areas, including such habitats as areas near gardens, lawns, grassy roadsides, vacant lots, and construction sites. In Europe, it has been found in such habitats as grassy roadsides, sandy lawns in commons areas, and sandy pastures. Roman Chamomile is still cultivated in flower and herbal gardens, from where it occasionally escapes, but rarely persists. Areas with a history of disturbance are preferred.
Faunal Associations: The nectar and pollen of the flowerheads probably attract small bees and various flies; wasps and beetles may visit the flowerheads to a lesser extent. Two aphids, Macrosiphoniella tanacetaria and Macrosiphoniella tapuskae, are known to feed on Roman Chamomile (Blackman & Eastop, 2013). A polyphagous leafhopper, Empoasca erigeron, also feeds on this plant (Dmitriev & Dietrich, 2010). At the present time, information about this plant's relationships with granivorous birds and herbivorous mammals is unavailable.
Photographic Location: An ornamental garden at the Urbana Public Library of Urbana, Illinois.
Comments: There are several species of plants in the Aster family that have daisy-like flowerheads with white petaloid rays. Many of these species have been introduced into North America from Eurasia as garden plants, including Roman Chamomile (Chamaemelum nobile). Roman Chamomile can be distinguished from most of these species by its highly fragrant foliage and crushed flowerheads, which have an apple-pineapple scent. One other species in this group that has naturalized in Illinois, German Chamomile (Matricaria chamomile), also has foliage and crushed flowerheads with a similar fruity scent. German Chamomile can be readily distinguished by its glabrous foliage, more erect habit, the hollow interior of its flowerheads, and the lack of chaffy scales between the disk florets. This latter plant is also an annual, rather than a perennial. Both of these species have been used as ingredients in Chamomile tea, and the chemical constituents of their flowerheads are said to have relaxing and soothing properties. An alternative scientific name for Roman Chamomile is Anthemis nobilis, and it has other common names, including Low Chamomile, English Chamomile, and Garden Chamomile.
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Miss Chen
2018年07月31日
Description: This plant is a spring or summer annual that becomes 3-10" tall, branching occasionally. The narrow round stems are covered with white hairs. The lower leaves are opposite, while the middle to upper leaves are alternate. These leaves are up to 1" long and 1/6" (4 mm.) across. They are linear-oblong or linear-oblanceolate, with margins that are ciliate and smooth. From the axil of each middle or upper leaf, a single flower develops from a slender pedicel about 1" long. Sometimes a second flower develops from the leaf axil. Like the stems, these pedicels are covered with white hairs. The flowers are up to 1/4" in length. The corolla is tubular, with 5 spreading lobes in the front and a short spur in the back. The corolla has a small opening at the throat and is more or less two-lipped with 2 upper lobes and 3 lower lobes. It is variously colored, usually some shade of lavender, light purple, or white. Sometimes the corolla is bicolored, with the upper lobes lavender or light purple and the lower lobes white. There are usually a few hairs at the base of the lower lobes. The calyx is green or purplish green and quite hairy. It has 5 oblanceolate lobes that are almost as long as the corolla.
The blooming period occurs during the summer and it lasts about a month for a colony of plants. There is no noticeable floral scent. Each flower is replaced by an ovoid capsule that contains numerous brown seeds. These seeds are tiny enough to be dispersed by gusts of wind. The root system consists of a slender taproot. This plant spreads by reseeding itself.
Cultivation: This little plant prefers dry sunny conditions and a sterile soil that is sandy or gravelly. It also grows in partial sun and less dry conditions, in which case it will become somewhat taller and more leafy. In fertile soil, this plant is not competitive with taller vegetation. Alkaline soil is readily tolerated.
Range & Habitat: The non-native Dwarf Snapdragon has been reported from most counties in Illinois (see Distribution Map). It is occasional to locally common. Habitats include gravelly areas along railroads (including the ballast), sandy or gravelly areas along roads, gravelly borders along buildings, and sterile waste areas. Disturbed areas are preferred. Dwarf Snapdragon is especially common along railroads in part because the wind gusts produced by passing trains help to disperse the tiny seeds. This plant is adventive from the Mediterranean area of Europe. It is less common along railroad tracks than formerly because of the application of herbicides.
Faunal Association: Little information is available about floral-faunal relationships. The flowers are pollinated by small bees, although they are also capable of self-pollination. The seeds are too small to be of any interest to birds, and the insubstantial foliage is unlikely to provide much nourishment to mammalian herbivores. Humans assist in the dispersal of the seeds of this plant because of their passing trains and motor vehicles, as noted above.
Photographic Location: A border along a building that was filled with pebbles. This building was located along a railroad in Urbana, Illinois.
Comments: Sometimes this plant is called "Small Snapdragon" and "Lesser Toadflax." It resembles the Linaria spp. (Toadflaxes) somewhat, except the throat of its corolla is less obstructed by fuzzy hairs and a palate covers the lower lip. Dwarf Snapdragon is one of the members of a group of plants that colonize disturbed sterile soil; these species are ecologically significant because they help to stabilize and restore the fertility of the soil. An alternative spelling of the scientific name for this plant is Chaenorrhinum minus.
The blooming period occurs during the summer and it lasts about a month for a colony of plants. There is no noticeable floral scent. Each flower is replaced by an ovoid capsule that contains numerous brown seeds. These seeds are tiny enough to be dispersed by gusts of wind. The root system consists of a slender taproot. This plant spreads by reseeding itself.
Cultivation: This little plant prefers dry sunny conditions and a sterile soil that is sandy or gravelly. It also grows in partial sun and less dry conditions, in which case it will become somewhat taller and more leafy. In fertile soil, this plant is not competitive with taller vegetation. Alkaline soil is readily tolerated.
Range & Habitat: The non-native Dwarf Snapdragon has been reported from most counties in Illinois (see Distribution Map). It is occasional to locally common. Habitats include gravelly areas along railroads (including the ballast), sandy or gravelly areas along roads, gravelly borders along buildings, and sterile waste areas. Disturbed areas are preferred. Dwarf Snapdragon is especially common along railroads in part because the wind gusts produced by passing trains help to disperse the tiny seeds. This plant is adventive from the Mediterranean area of Europe. It is less common along railroad tracks than formerly because of the application of herbicides.
Faunal Association: Little information is available about floral-faunal relationships. The flowers are pollinated by small bees, although they are also capable of self-pollination. The seeds are too small to be of any interest to birds, and the insubstantial foliage is unlikely to provide much nourishment to mammalian herbivores. Humans assist in the dispersal of the seeds of this plant because of their passing trains and motor vehicles, as noted above.
Photographic Location: A border along a building that was filled with pebbles. This building was located along a railroad in Urbana, Illinois.
Comments: Sometimes this plant is called "Small Snapdragon" and "Lesser Toadflax." It resembles the Linaria spp. (Toadflaxes) somewhat, except the throat of its corolla is less obstructed by fuzzy hairs and a palate covers the lower lip. Dwarf Snapdragon is one of the members of a group of plants that colonize disturbed sterile soil; these species are ecologically significant because they help to stabilize and restore the fertility of the soil. An alternative spelling of the scientific name for this plant is Chaenorrhinum minus.
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Pommy Mommy：My drawf SNAPDRAGONS planted from seed. I live in Ohio and I cannot believe how phenomenal they grew for me! I ended up getting four different varieties of colors each plant is two colors, pink and yellow, orange and yellow, red and orange, and red and yellow have all bloomed so far and I just found another flower pot with more growing as a border (a lot of times when I have sure seeds make a little border ring around the edge of the pot). I just planted my Hundred flower pot! YES, you read that correctly 100! and those are just what I have in pots, I don't count with planted in the ground.
文章
Miss Chen
2018年07月31日
Description: This little plant is a winter or spring annual about 2-6" tall. A mature plant becomes tufted at the base, sending up multiple stems. These stems are green and pubescent. The opposite leaves are up to ¾" long and about half as much across. These leaves are broadly oblong or ovate-oblong, green, and pubescent; they have conspicuous central veins, smooth margins, and sessile bases.
The upper stems terminate in small cymes or individual flowers; sometimes the lower cymes branch into secondary cymes of flowers. The peduncles and pedicels of these cymes are light green and pubescent. At the base of each peduncle, there is a pair of green leaf-like bracts. These bracts are broadly lanceolate-oblong or lanceolate-ovate, pubescent, and smooth along the margins; some of the upper bracts have thin translucent margins toward their tips (i.e., they are slightly scarious). These translucent margins are more apparent in mature or dried-out plants than young specimens. The flowers at the tips of the pedicels are up to ¼" across when they are fully open. Each flower has 5 white petals, 5 green sepals, 5 white styles, and 5 stamens with pale yellow anthers. Each petal has several pale lines at its base, while its tip is notched. The sepals are lanceolate and hairy; their margins are translucent. The blooming period occurs during the spring and lasts about 1 month; this is one of the earliest wildflowers to bloom during the spring. The flowers open up during spring days that are sunny and warm. Some plants begin to bloom when they are only 1" tall. Each flower is replaced by a cylindrical capsule containing manyDistribution Map small seeds. Each seed capsule is straight to slightly curved; there are 10 small teeth along its upper rim. The seeds are brown, somewhat flattened, and minutely warty or pebbly. The root system consists mostly of thin fibrous roots. This plant spreads by reseeding itself and it often forms small colonies.
Cultivation: The preference is full sun, moist to slightly dry conditions, and sterile soil with little ground vegetation. In Illinois, this little plant completes its growth cycle during the spring.
Range & Habitat: Small Mouse-Eared Chickweed is occasional in central and NE Illinois, while in other areas of the state it is uncommon or absent. This plant was accidentally introduced into the United States from Europe. Habitats consist of fields, disturbed grassy meadows, areas along roads, barren ground in lawns, and waste areas. Areas with a history of disturbance and environmental degradation are strongly preferred. This little plant tolerates road salt and other run-off chemicals better than most kinds of turf-grass; it also tolerates hardpan clay and gravel better than turf-grass.
Faunal Associations: Like other Chickweeds (Cerastium spp., Stellaria spp.), the flowers of this species attract small bees and Syrphid flies. While the foliage of Small Mouse-Eared Chickweed is potentially edible to rabbits, it is rarely eaten because of its diminutive size and early spring growth. Small granivorous songbirds (e.g., sparrows) may use the seeds as a minor source of food.
Photographic Location: A barren area along a roadside in Urbana, Illinois.
Comments: There are several Cerastium spp. (Mouse-Eared Chickweeds) in Illinois and they are difficult to distinguish from each other. I believe that the species in the photograph above is Cerastium pumilum (Small Mouse-Eared Chickweed) for the following reasons: 1) It is a short-lived annual that completes its life-cycle during the spring, 2) Each of its flowers has 5 stamens and 5 styles, 3) Its flowers always have 5 petals, and 4) Its floral bracts usually lack translucent margins, except for some of the upper bracts on mature plants. Other Mouse-Eared Chickweeds are perennials (e.g., Cerastium fontanum), or they have flowers with 10 stamens (e.g., Cerastium brachypetalum, Cerastium glomeratum), or they produce flowers with 4 petals (e.g., Cerastium diffusum), or all of their bracts have conspicuous translucent margins (e.g., Cerastium semidecandrum).
The upper stems terminate in small cymes or individual flowers; sometimes the lower cymes branch into secondary cymes of flowers. The peduncles and pedicels of these cymes are light green and pubescent. At the base of each peduncle, there is a pair of green leaf-like bracts. These bracts are broadly lanceolate-oblong or lanceolate-ovate, pubescent, and smooth along the margins; some of the upper bracts have thin translucent margins toward their tips (i.e., they are slightly scarious). These translucent margins are more apparent in mature or dried-out plants than young specimens. The flowers at the tips of the pedicels are up to ¼" across when they are fully open. Each flower has 5 white petals, 5 green sepals, 5 white styles, and 5 stamens with pale yellow anthers. Each petal has several pale lines at its base, while its tip is notched. The sepals are lanceolate and hairy; their margins are translucent. The blooming period occurs during the spring and lasts about 1 month; this is one of the earliest wildflowers to bloom during the spring. The flowers open up during spring days that are sunny and warm. Some plants begin to bloom when they are only 1" tall. Each flower is replaced by a cylindrical capsule containing manyDistribution Map small seeds. Each seed capsule is straight to slightly curved; there are 10 small teeth along its upper rim. The seeds are brown, somewhat flattened, and minutely warty or pebbly. The root system consists mostly of thin fibrous roots. This plant spreads by reseeding itself and it often forms small colonies.
Cultivation: The preference is full sun, moist to slightly dry conditions, and sterile soil with little ground vegetation. In Illinois, this little plant completes its growth cycle during the spring.
Range & Habitat: Small Mouse-Eared Chickweed is occasional in central and NE Illinois, while in other areas of the state it is uncommon or absent. This plant was accidentally introduced into the United States from Europe. Habitats consist of fields, disturbed grassy meadows, areas along roads, barren ground in lawns, and waste areas. Areas with a history of disturbance and environmental degradation are strongly preferred. This little plant tolerates road salt and other run-off chemicals better than most kinds of turf-grass; it also tolerates hardpan clay and gravel better than turf-grass.
Faunal Associations: Like other Chickweeds (Cerastium spp., Stellaria spp.), the flowers of this species attract small bees and Syrphid flies. While the foliage of Small Mouse-Eared Chickweed is potentially edible to rabbits, it is rarely eaten because of its diminutive size and early spring growth. Small granivorous songbirds (e.g., sparrows) may use the seeds as a minor source of food.
Photographic Location: A barren area along a roadside in Urbana, Illinois.
Comments: There are several Cerastium spp. (Mouse-Eared Chickweeds) in Illinois and they are difficult to distinguish from each other. I believe that the species in the photograph above is Cerastium pumilum (Small Mouse-Eared Chickweed) for the following reasons: 1) It is a short-lived annual that completes its life-cycle during the spring, 2) Each of its flowers has 5 stamens and 5 styles, 3) Its flowers always have 5 petals, and 4) Its floral bracts usually lack translucent margins, except for some of the upper bracts on mature plants. Other Mouse-Eared Chickweeds are perennials (e.g., Cerastium fontanum), or they have flowers with 10 stamens (e.g., Cerastium brachypetalum, Cerastium glomeratum), or they produce flowers with 4 petals (e.g., Cerastium diffusum), or all of their bracts have conspicuous translucent margins (e.g., Cerastium semidecandrum).
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文章
Miss Chen
2018年07月31日
Description: This plant is a winter or spring annual that becomes 4-16" tall, usually forming a tuft of leafy stems that are ascending to sprawling. These stems are branched at the base near the crown of the plant, otherwise they are unbranched. Individual stems are light green, terete, and glandular-hairy. Pairs of opposite leaves occur along these stems (typically at intervals of 1-2½"). These leaves are ¾-2" long, 5-9 mm. across, and elliptic, oblong-lanceolate, or oblong-oblanceolate in shape. The leaf margins are smooth (entire) and slightly ciliate. The leaf surfaces are medium green and either sparsely short-pubescent or hairless. Each leaf has a prominent central vein.
The upper stems terminate in either cymes or compound cymes of flowers (usually the latter); these cymes are dichotomously branched and variable in size. Each terminal branch of the inflorescence typically has 3 flowers with divergent slender pedicels up to 1¼" long. While the flower buds are nodding, the flowers are more erect. Similar to the stems, the branches and pedicels of each inflorescence are light green, terete, and glandular-pubescent. At the base of each pair of branches in an inflorescence, there is a pair of leafy bracts up to ¾" and 5 mm. across. These bracts are lanceolate in shape and they lack membranous margins. The flowers are up to ¼" across while they are in bloom. Each flower has 5 white petals with notched tips, 5 green sepals, an ovary with 5 styles, and 10 stamens (usually). The sepals are lanceolate in shape with membranous margins and short-pubescent; they are about 3-5 mm. long. The petals are the same length or a little longer than the sepals. The blooming period occurs from mid-spring to early summer, lasting about 1 month. Usually, only a few flowers are in bloom at the same time. Sometimes cleistogamous flowers that fail to open are produced.Distribution Map Afterwards, the flowers are replaced by cylindrical seed capsules that become 8-12 mm. long at maturity. Like the flowerbuds, they tend to nod downward. Mature seed capsules are membranous, light tan, longitudinally veined, and often slightly curved; they are more than twice as long as the sepals. Each seed capsule has an open rim at its apex with 10 tiny teeth. Each seed capsule contains several tiny seeds about 0.5 mm. in length. The seeds are obovoid, somewhat flattened, brownish, and minutely tuberculate (warty). The root system system consists of a shallow spreading taproot.
Cultivation: The preference is full sun to light shade and moist conditions. Nodding Chickweed is not particular about soil. Most growth and development occurs during the spring when the weather is cool and moist, after which the foliage dies down.
Range & Habitat: The native Nodding Chickweed is occasional to locally common in most areas of Illinois. Habitats include floodplain woodlands, streambanks in wooded areas, ravines and ledges along streams, gravel bars along rivers, weedy meadows, nursery plots, and moist waste areas. Nodding Chickweed occurs in both natural areas and human-mediated environments. In natural areas, it tends to occur in places where there is some disturbance by the action of water (e.g., soil erosion or deposits of gravel).
Faunal Associations: The flowers are cross-pollinated by honeybees, Halictid bees (Halictus spp., Lasioglossum spp.), small butterflies, Syrphid flies, and other flies (Robertson, 1929). Both nectar and pollen are available as floral rewards. The caterpillars and cutworms of various moths are known to feed on chickweeds (Stellaria spp., Cerastium spp.). These moth species include Haematopis grataria (Chickweed Geometer), Lobocleta ossularia (Drab Brown Wave), Agrotis venerabilis (Venerable Dart), Hyles lineata (White-Lined Sphinx), Feltia jaculifera (Dingy Cutworm), Xestia badinodis (Spot-Sided Cutworm), and Xanthorhoe ferrugata (Red Twin-Spot). Vertebrate animals also feed on these plants to some extent. Various sparrows and other granivorous songbirds eat the seeds, while deer, rabbits, and domesticated farm animals (cattle, horses, sheep, & pigs) occasionally browse on the foliage.
Photographic Location: A gravel bar along a river in a wooded area of Pine Hills State Nature Preserve in west-central Indiana.
Comments: Notwithstanding its weedy appearance and habits, this is one of the native chickweeds in Illinois. It is a rather floppy plant with small white flowers. Nodding Chickweed can be distinguished from other chickweeds (Stellaria spp., Cerastium spp.) by the shape of its leaves, diffuse inflorescence, and structure of its flowers. In particular, the pedicels of its flowers are rather long (1" in length or more) and divergent, while its flowerbuds and seed capsules nod downward. Among the Mouse-Eared Chickweeds (Cerastium spp.), Nodding Chickweed has rather long and narrow leaves. Some authorities consider the more western Cerastium brachypodum to be a variety of Nodding Chickweed, or Cerastium nutans obtectum. This latter species (or variety) tends to have more hairy leaves and its pedicels are shorter (less than 1" in length).
The upper stems terminate in either cymes or compound cymes of flowers (usually the latter); these cymes are dichotomously branched and variable in size. Each terminal branch of the inflorescence typically has 3 flowers with divergent slender pedicels up to 1¼" long. While the flower buds are nodding, the flowers are more erect. Similar to the stems, the branches and pedicels of each inflorescence are light green, terete, and glandular-pubescent. At the base of each pair of branches in an inflorescence, there is a pair of leafy bracts up to ¾" and 5 mm. across. These bracts are lanceolate in shape and they lack membranous margins. The flowers are up to ¼" across while they are in bloom. Each flower has 5 white petals with notched tips, 5 green sepals, an ovary with 5 styles, and 10 stamens (usually). The sepals are lanceolate in shape with membranous margins and short-pubescent; they are about 3-5 mm. long. The petals are the same length or a little longer than the sepals. The blooming period occurs from mid-spring to early summer, lasting about 1 month. Usually, only a few flowers are in bloom at the same time. Sometimes cleistogamous flowers that fail to open are produced.Distribution Map Afterwards, the flowers are replaced by cylindrical seed capsules that become 8-12 mm. long at maturity. Like the flowerbuds, they tend to nod downward. Mature seed capsules are membranous, light tan, longitudinally veined, and often slightly curved; they are more than twice as long as the sepals. Each seed capsule has an open rim at its apex with 10 tiny teeth. Each seed capsule contains several tiny seeds about 0.5 mm. in length. The seeds are obovoid, somewhat flattened, brownish, and minutely tuberculate (warty). The root system system consists of a shallow spreading taproot.
Cultivation: The preference is full sun to light shade and moist conditions. Nodding Chickweed is not particular about soil. Most growth and development occurs during the spring when the weather is cool and moist, after which the foliage dies down.
Range & Habitat: The native Nodding Chickweed is occasional to locally common in most areas of Illinois. Habitats include floodplain woodlands, streambanks in wooded areas, ravines and ledges along streams, gravel bars along rivers, weedy meadows, nursery plots, and moist waste areas. Nodding Chickweed occurs in both natural areas and human-mediated environments. In natural areas, it tends to occur in places where there is some disturbance by the action of water (e.g., soil erosion or deposits of gravel).
Faunal Associations: The flowers are cross-pollinated by honeybees, Halictid bees (Halictus spp., Lasioglossum spp.), small butterflies, Syrphid flies, and other flies (Robertson, 1929). Both nectar and pollen are available as floral rewards. The caterpillars and cutworms of various moths are known to feed on chickweeds (Stellaria spp., Cerastium spp.). These moth species include Haematopis grataria (Chickweed Geometer), Lobocleta ossularia (Drab Brown Wave), Agrotis venerabilis (Venerable Dart), Hyles lineata (White-Lined Sphinx), Feltia jaculifera (Dingy Cutworm), Xestia badinodis (Spot-Sided Cutworm), and Xanthorhoe ferrugata (Red Twin-Spot). Vertebrate animals also feed on these plants to some extent. Various sparrows and other granivorous songbirds eat the seeds, while deer, rabbits, and domesticated farm animals (cattle, horses, sheep, & pigs) occasionally browse on the foliage.
Photographic Location: A gravel bar along a river in a wooded area of Pine Hills State Nature Preserve in west-central Indiana.
Comments: Notwithstanding its weedy appearance and habits, this is one of the native chickweeds in Illinois. It is a rather floppy plant with small white flowers. Nodding Chickweed can be distinguished from other chickweeds (Stellaria spp., Cerastium spp.) by the shape of its leaves, diffuse inflorescence, and structure of its flowers. In particular, the pedicels of its flowers are rather long (1" in length or more) and divergent, while its flowerbuds and seed capsules nod downward. Among the Mouse-Eared Chickweeds (Cerastium spp.), Nodding Chickweed has rather long and narrow leaves. Some authorities consider the more western Cerastium brachypodum to be a variety of Nodding Chickweed, or Cerastium nutans obtectum. This latter species (or variety) tends to have more hairy leaves and its pedicels are shorter (less than 1" in length).
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