文章
Miss Chen
2018年07月31日
Description: This plant is a winter or spring annual that becomes 4-10" tall. It has a small tuft of erect to ascending leafy stems; these stems are light green to dark purple, terete, and hairy. Along each stem, there are pairs of sessile opposite leaves at intervals. Individual leaves are up to ¾" long and about half as much across; they are medium green, bluntly ovate, broadly oblong, or obovate with smooth margins. Both the lower and upper surfaces of each leaf are covered with hairs. The hairs on the stems and leaves may have a sticky texture from minute glandular secretions.
Each stem terminates in a dense cluster of flowers; in addition, individual or small clusters of flowers may develop from the axils of the upper leaves. Each small flower is about ¼" across, consisting of 5 white petals, 5 green sepals, 10 stamens, and a pistil with 5 styles. The tips of the petals are notched. The lanceolate sepals have long forward-pointing hairs and membranous margins. The hairy pedicel of each flower is no longer than 5 mm. (1/5") in length, even when it has transformed into a seed capsule. The blooming period occurs from mid-spring to early summer and lasts about 3-4 weeks. Each flower transforms into a cylindrical seed capsule that is up to twice the length of the persistent sepals. This seed capsule is membranous along the sides and open at the apex, where there are 10 tiny teeth. At the bottom of this capsule, there are several tiny seeds. Each seed is obovoid or heart-shaped, somewhat flattened, and minutely pebbly on the outer surface. The root system is shallow and fibrous. This plant spreads by reseeding itself; it often forms colonies in favorable habitats.
Cultivation: This little weed prefers partial to full sun and moist to slightly dry conditions. It is often found in soil containing loam, clay-loam, or other material. This species can invade lawns to some extent.
Range & Habitat: Glomerate Mouse-Eared Chickweed is occasional throughout Illinois (see Distribution Map), where it is not native. Habitats include openings in rocky woodlands, grassy meadows, lawns, pastures, fallow fields, roadsides, and waste ground. Areas with a history of disturbance are preferred. This species is native to Eurasia.
Faunal Associations: The nectar and pollen of the flowers attract small bees (Halictid & others) and flies (Syrphid & others). The caterpillars of the moths Agrostis venerabilis (Venerable Dart), Haematopis grataria (Chickweed Geometer), and Lobocleta ossularia (Drab Brown Wave) feed on chickweeds. Among vertebrate animals, the Mourning Dove and various sparrows occasionally eat the seeds, while the foliage is eaten by the Cottontail Rabbit and Woodchuck.
Photographic Location: A lawn at a state park in west-central Indiana.
Comments: The distinctive characteristic of this chickweed is its dense cluster(s) of flowers. In particular, the pedicels of the flowers are the same length or shorter than the sepals (5 mm. or less). Several other species of chickweeds are similar in appearance, but at least some of their pedicels exceed 5 mm. in length (particularly when their flowers have transformed into seed capsules). The sepals of Glomerate Mouse-Eared Chickweed are somewhat unusual because they are covered with long forward-pointing hairs that may extend beyond their margins; other species of chickweed have sepals with shorter hairs. In general, the various species in the Cerastium genus are called "Mouse-Eared Chickweeds" because of the shape and hairiness of their leaves; these species usually have 10 stamens and 5 styles per flower. A scientific synonym of Glomerate Mouse-Eared Chickweed is Cerastium viscosum. Because of this defunct scientific name, this species is sometimes called "Clammy Mouse-Eared Chickweed."
Each stem terminates in a dense cluster of flowers; in addition, individual or small clusters of flowers may develop from the axils of the upper leaves. Each small flower is about ¼" across, consisting of 5 white petals, 5 green sepals, 10 stamens, and a pistil with 5 styles. The tips of the petals are notched. The lanceolate sepals have long forward-pointing hairs and membranous margins. The hairy pedicel of each flower is no longer than 5 mm. (1/5") in length, even when it has transformed into a seed capsule. The blooming period occurs from mid-spring to early summer and lasts about 3-4 weeks. Each flower transforms into a cylindrical seed capsule that is up to twice the length of the persistent sepals. This seed capsule is membranous along the sides and open at the apex, where there are 10 tiny teeth. At the bottom of this capsule, there are several tiny seeds. Each seed is obovoid or heart-shaped, somewhat flattened, and minutely pebbly on the outer surface. The root system is shallow and fibrous. This plant spreads by reseeding itself; it often forms colonies in favorable habitats.
Cultivation: This little weed prefers partial to full sun and moist to slightly dry conditions. It is often found in soil containing loam, clay-loam, or other material. This species can invade lawns to some extent.
Range & Habitat: Glomerate Mouse-Eared Chickweed is occasional throughout Illinois (see Distribution Map), where it is not native. Habitats include openings in rocky woodlands, grassy meadows, lawns, pastures, fallow fields, roadsides, and waste ground. Areas with a history of disturbance are preferred. This species is native to Eurasia.
Faunal Associations: The nectar and pollen of the flowers attract small bees (Halictid & others) and flies (Syrphid & others). The caterpillars of the moths Agrostis venerabilis (Venerable Dart), Haematopis grataria (Chickweed Geometer), and Lobocleta ossularia (Drab Brown Wave) feed on chickweeds. Among vertebrate animals, the Mourning Dove and various sparrows occasionally eat the seeds, while the foliage is eaten by the Cottontail Rabbit and Woodchuck.
Photographic Location: A lawn at a state park in west-central Indiana.
Comments: The distinctive characteristic of this chickweed is its dense cluster(s) of flowers. In particular, the pedicels of the flowers are the same length or shorter than the sepals (5 mm. or less). Several other species of chickweeds are similar in appearance, but at least some of their pedicels exceed 5 mm. in length (particularly when their flowers have transformed into seed capsules). The sepals of Glomerate Mouse-Eared Chickweed are somewhat unusual because they are covered with long forward-pointing hairs that may extend beyond their margins; other species of chickweed have sepals with shorter hairs. In general, the various species in the Cerastium genus are called "Mouse-Eared Chickweeds" because of the shape and hairiness of their leaves; these species usually have 10 stamens and 5 styles per flower. A scientific synonym of Glomerate Mouse-Eared Chickweed is Cerastium viscosum. Because of this defunct scientific name, this species is sometimes called "Clammy Mouse-Eared Chickweed."
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文章
Miss Chen
2018年07月30日
Description: This herbaceous perennial plant is tufted at the base, producing multiple stems up to 1½' long, although they are usually about one-half of this length or less. These stems are ascending to widely spreading; they are green or purple, terete (round in cross-section), and pubescent. The opposite leaves are up to 1" long and 1/3" across (or a little larger); they are variably shaped, including lanceolate-ovate, oval-oblong, or broadly oblanceolate. The leaves are pubescent, smooth along the margins, and sessile at the base; they have a prominent central vein on the upper surface. The stems often terminate in small cymes (flat-headed clusters) of 1-5 small flowers; both the peduncles and pedicelsClose-up of Flowers of these cymes are pubescent. At the base of each cyme, there is a pair of leafy bracts with thin translucent margins. Each flower is up to ¼" across, consisting of 5 green sepals, 5 white petals with notched tips, 10 stamens with pale yellow anthers, and 5 styles; some plants may produce flowers with fewer than 10 stamens. The sepals are lanceolate, pubescent, and translucent along their margins; they are about the same length as the petals. The blooming period occurs intermittently from late spring to early fall and may last several months for individual plants. Each flower is replaced by a cylindrical seed capsule with 10 small teeth along its upper rim. Each seed capsule containing several small seeds. The seeds are somewhat flattened and minutely warty or pebbly. The root system is mostly fibrous. This plant reproduces primarily by reseeding itself; it can also form vegetative offsets when the nodes of the lower stems develop rootlets while lying on moist ground.
Cultivation: The preference is full sun to light shade and moist to slightly dry conditions. This plant can tolerate a broad range of soils, including those that contain loam, clay-loam, and pebbly or gravelly material. Common Mouse-Eared Chickweed is more often found in fertile soil than other Cerastium spp. (Mouse-Eared Chickweeds). It is a larger plant that can tolerate more competition from other kinds of vegetation.
Range & Habitat: Common Mouse-Eared Chickweed occurs in every county of Illinois; it is quite common (see Distribution Map). This species was accidentally introduced into North America from Eurasia. Habitats include fields, pastures, lawns, gardens, roadsides, areas along railroads, areas adjacent to buildings, vacant lots, degraded grassy meadows, and waste areas. Areas with a history of disturbance provide preferred habitats.
Faunal Associations: The flowers attract various bees and flies; these insects suck nectar primarily, although some Syrphid flies feed on the pollen and some of the smaller bees (e.g., Halictid bees) collect pollen for their larvae. The caterpillars of several moths feed on the foliage of Chickweeds (Cerastium spp., Stellaria spp.), including Agrostis venerabilis (Venerable Dart), Haematopis grataria (Chickweed Geometer), and Lobocleta ossularia (Drab Brown Wave). Sparrows and other small granivorous songbirds eat the seeds of Chickweeds. Because Common Mouse-Eared Chickweed is one of the larger Chickweeds that grows during the summer, the Cottontail Rabbit nibbles on its foliage occasionally.
Photographic Location: An area adjacent to a building in Champaign-Urbana, Illinois.
Comments: This adaptable plant is probably the most common Cerastium sp. (Mouse-Eared Chickweed) in Illinois. Compared to the similar Stellaria spp. (Chickweeds), Mouse-Eared Chickweeds usually have more pubescent leaves and their flowers have 5 styles, rather than 3. Among the many Mouse-Eared Chickweeds that occur in Illinois (most of them are introductions from Eurasia), Common Mouse-Eared Chickweed is the only one with a perennial habit and it is often larger in size. It also blooms later in the year (typically during the summer), while the annual species of Mouse-Eared Chickweed bloom primarily during the spring. A scientific synonym of Common Mouse-Eared Chickweed is Cerastium vulgatum.
Cultivation: The preference is full sun to light shade and moist to slightly dry conditions. This plant can tolerate a broad range of soils, including those that contain loam, clay-loam, and pebbly or gravelly material. Common Mouse-Eared Chickweed is more often found in fertile soil than other Cerastium spp. (Mouse-Eared Chickweeds). It is a larger plant that can tolerate more competition from other kinds of vegetation.
Range & Habitat: Common Mouse-Eared Chickweed occurs in every county of Illinois; it is quite common (see Distribution Map). This species was accidentally introduced into North America from Eurasia. Habitats include fields, pastures, lawns, gardens, roadsides, areas along railroads, areas adjacent to buildings, vacant lots, degraded grassy meadows, and waste areas. Areas with a history of disturbance provide preferred habitats.
Faunal Associations: The flowers attract various bees and flies; these insects suck nectar primarily, although some Syrphid flies feed on the pollen and some of the smaller bees (e.g., Halictid bees) collect pollen for their larvae. The caterpillars of several moths feed on the foliage of Chickweeds (Cerastium spp., Stellaria spp.), including Agrostis venerabilis (Venerable Dart), Haematopis grataria (Chickweed Geometer), and Lobocleta ossularia (Drab Brown Wave). Sparrows and other small granivorous songbirds eat the seeds of Chickweeds. Because Common Mouse-Eared Chickweed is one of the larger Chickweeds that grows during the summer, the Cottontail Rabbit nibbles on its foliage occasionally.
Photographic Location: An area adjacent to a building in Champaign-Urbana, Illinois.
Comments: This adaptable plant is probably the most common Cerastium sp. (Mouse-Eared Chickweed) in Illinois. Compared to the similar Stellaria spp. (Chickweeds), Mouse-Eared Chickweeds usually have more pubescent leaves and their flowers have 5 styles, rather than 3. Among the many Mouse-Eared Chickweeds that occur in Illinois (most of them are introductions from Eurasia), Common Mouse-Eared Chickweed is the only one with a perennial habit and it is often larger in size. It also blooms later in the year (typically during the summer), while the annual species of Mouse-Eared Chickweed bloom primarily during the spring. A scientific synonym of Common Mouse-Eared Chickweed is Cerastium vulgatum.
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文章
Miss Chen
2018年07月30日
Description: This plant is a winter or spring annual about 4-16" tall that sometimes branches from the base, forming a tuft of leafy stems. Each erect to ascending stem is light green to pale purplish green, terete, and evenly glandular-pubescent. Several pairs of opposite leaves occur along each stem; sometimes tufts of smaller leaves develop from the axils of the lower opposite leaves. These leaves are up to 1" long and 1/5" (5 mm.) across; they are linear, linear-oblong, or oblong, and sessile against their stems. Each leaf is hairless on the upper surface with a single prominent vein; the lower surface is also hairless, except for some glandular hairs along the central vein. The leaf margins are smooth and ciliate.
Each stem terminates in a corymb (flat-headed cluster) or compound corymb of flowers. The peduncle of each corymb is similar to the stem, except that it has a pair of leafy bracts at its base; it can be several inches long. Compound corymbs have branched ascending peduncles. Each flower is up to ¼" across; it has 5 white petals, 5 green sepals, 10 stamens, and 3 tiny white styles at the apex of the light green ovary. The petals are cleft at their tips, while the sepals are glandular-pubescent. The pedicel of each flower is up to ½" long and glandular-pubescent. The leafy bracts are linear-lanceolate to ovate, glandular-pubescent on their undersides, and slightly membranous along their margins at maturity; they are smaller in size than the leaves (½" long or less). The blooming period occurs during the late spring and lasts about 3 weeks. There is no noticeable floral scent. Each flower is replaced by a cylindrical seed capsule that is up to 10 mm. (3/8") long. At maturity, this seed capsule becomes membranous and open at its apex; there are 6 small teeth along its upper rim. There are numerous small seeds within each capsule; each seed is pale brown, minutely warty, ovoid-obovoid in shape, and somewhat flattened. The root system consists of a slender branching taproot with fine fibrous roots. This plant spreads by reseeding itself and occasionally forms colonies.
Cultivation: Typical growing conditions consist of full sunlight and average levels of moisture. Three-styled Chickweed adapts readily to loam or clay-loam soil; sandy or gravelly soil may be tolerated as well. Because this chickweed is taller and more erect than most, regular mowing may inhibit its spread.
Range & Habitat: The adventive Three-Styled Chickweed is a rare weed in Illinois; it has been observed in only a few counties of south-central and east-central Illinois (see Distribution Map). This species is native to southern Europe and parts of Asia. The earliest collection of this species in the United States occurred in the state of Washington during the 1960's. Since that time, it has been observed in several other states (both eastern & western) and appears to be spreading. Habitats include disturbed areas with low grassy or weedy vegetation and the upper slopes of ditches. Recent construction activity mayClose-up of Flower have introduced this species to Champaign County in Illinois.
Faunal Associations: This information applies to chickweeds, both native and introduced, that are typically found in sunny meadows and similar habitats. The nectar and pollen of the flowers attract small bees (Halictid & others) and flies (Syrphid & others). The caterpillars of the moths Agrostis venerabilis (Venerable Dart), Haematopis grataria (Chickweed Geometer), and Lobocleta ossularia (Drab Brown Wave) feed on chickweeds. Among vertebrate animals, the seeds are a source of food for the Mourning Dove and various sparrows, while the foliage is occasionally eaten by the Cottontail Rabbit.
Photographic Location: The upper slope of a drainage ditch in Urbana, Illinois. If the photograph of the flower close-up is examined closely, it is possible to see the 3 tiny white styles; they are surrounded by the yellow anthers of the stamens.
Comments: Among Cerastium spp. (Mouse-Eared Chickweeds), this chickweed is highly unusual because its flowers have 3 styles, rather than 5 styles. This characteristic is more typical of Stellaria spp. (Chickweeds). However, other characteristics of its flowers (e.g., the presence of 10 stamens & the shape of its petals) and the even pubescence of its stems are more typical of the Mouse-Eared Chickweeds. Three-Styled Chickweed is a little taller than most of these species and its leaves are more slender. Otherwise, it is rather ordinary looking. Another common name is Doubtful Chickweed, which is derived from the scientific name.
Each stem terminates in a corymb (flat-headed cluster) or compound corymb of flowers. The peduncle of each corymb is similar to the stem, except that it has a pair of leafy bracts at its base; it can be several inches long. Compound corymbs have branched ascending peduncles. Each flower is up to ¼" across; it has 5 white petals, 5 green sepals, 10 stamens, and 3 tiny white styles at the apex of the light green ovary. The petals are cleft at their tips, while the sepals are glandular-pubescent. The pedicel of each flower is up to ½" long and glandular-pubescent. The leafy bracts are linear-lanceolate to ovate, glandular-pubescent on their undersides, and slightly membranous along their margins at maturity; they are smaller in size than the leaves (½" long or less). The blooming period occurs during the late spring and lasts about 3 weeks. There is no noticeable floral scent. Each flower is replaced by a cylindrical seed capsule that is up to 10 mm. (3/8") long. At maturity, this seed capsule becomes membranous and open at its apex; there are 6 small teeth along its upper rim. There are numerous small seeds within each capsule; each seed is pale brown, minutely warty, ovoid-obovoid in shape, and somewhat flattened. The root system consists of a slender branching taproot with fine fibrous roots. This plant spreads by reseeding itself and occasionally forms colonies.
Cultivation: Typical growing conditions consist of full sunlight and average levels of moisture. Three-styled Chickweed adapts readily to loam or clay-loam soil; sandy or gravelly soil may be tolerated as well. Because this chickweed is taller and more erect than most, regular mowing may inhibit its spread.
Range & Habitat: The adventive Three-Styled Chickweed is a rare weed in Illinois; it has been observed in only a few counties of south-central and east-central Illinois (see Distribution Map). This species is native to southern Europe and parts of Asia. The earliest collection of this species in the United States occurred in the state of Washington during the 1960's. Since that time, it has been observed in several other states (both eastern & western) and appears to be spreading. Habitats include disturbed areas with low grassy or weedy vegetation and the upper slopes of ditches. Recent construction activity mayClose-up of Flower have introduced this species to Champaign County in Illinois.
Faunal Associations: This information applies to chickweeds, both native and introduced, that are typically found in sunny meadows and similar habitats. The nectar and pollen of the flowers attract small bees (Halictid & others) and flies (Syrphid & others). The caterpillars of the moths Agrostis venerabilis (Venerable Dart), Haematopis grataria (Chickweed Geometer), and Lobocleta ossularia (Drab Brown Wave) feed on chickweeds. Among vertebrate animals, the seeds are a source of food for the Mourning Dove and various sparrows, while the foliage is occasionally eaten by the Cottontail Rabbit.
Photographic Location: The upper slope of a drainage ditch in Urbana, Illinois. If the photograph of the flower close-up is examined closely, it is possible to see the 3 tiny white styles; they are surrounded by the yellow anthers of the stamens.
Comments: Among Cerastium spp. (Mouse-Eared Chickweeds), this chickweed is highly unusual because its flowers have 3 styles, rather than 5 styles. This characteristic is more typical of Stellaria spp. (Chickweeds). However, other characteristics of its flowers (e.g., the presence of 10 stamens & the shape of its petals) and the even pubescence of its stems are more typical of the Mouse-Eared Chickweeds. Three-Styled Chickweed is a little taller than most of these species and its leaves are more slender. Otherwise, it is rather ordinary looking. Another common name is Doubtful Chickweed, which is derived from the scientific name.
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文章
Miss Chen
2018年07月30日
Description: This plant is an annual about 3-8" tall that branches occasionally, and it is more or less erect. The stems, leaves, and calyx of the flowers are greyish green and hairless. The slender stems are irregularly angular. The opposite leaves are up to 1" long and ¾" across, becoming smaller as they ascend the stems. They are variably shaped, smooth along the margins, and sessile or slightly clasping the stems. The lower leaves are ovoid or ovate with blunt tips, while the upper leaves are often lanceolate or oblong. Their texture is slightly fleshy and succulent. There is no tuft of basal leaves at the base of the plant. The upper stems terminate in small cymes or flat-headed panicles of flowers; some cymes of flowers may be produced from the axils of the upper leaves as well. Each flower has a narrow tubular corolla that is about ½" long; at its apex, this corolla divides into 5 spreading lobes up to ¼" across. These petal-like lobes are narrow and pink. At the base of the flower, there is a tubular calyx with 5 lobes that are very narrow and long. These calyx lobes are appressed against the base of the tubular corolla and at least half its length (sometimes they are nearly as long as the corolla). At the narrow throat of the flower, there are several exserted stamens with yellow anthers. Each flower has a short pedicel at least 1/8" long. The blooming period occurs during the summer and early fall and lasts about 2-3 months. As older flowers begin to fade away, the area that is enclosed by the lobes of their calyxes begins to swell until ovoid seed capsules are formed. Each seed capsule is open at the top and has 5 recurved teeth along its upper rim. Each of these capsules contains several tiny seeds that can be blown about by the wind or float on water. The root system consists of shallow fibrous roots. This plant spreads by reseeding itself.
Cultivation: Typical growing conditions are full sun and a moist soil that contains loam, clay-loam, or gravelly material. A limy soil and occasional flooding are tolerated.
Range & Habitat: Branching Centaury is an uncommon plant that is originally from Europe. It occurs primarily in a few counties in NE Illinois and does not appear to be spreading (see Distribution Map). The webmaster recently found a small colony of plants growing in Champaign County, Illinois. Habitats include moist depressions in grassy areas along roads and railroads. So far, this species is restricted to highly disturbed habitats.
Faunal Associations: Little information about floral-faunal relationships is available for this species. The structure of the flowers suggests that long-tongued bees, small butterflies, and skippers occasionally pollinate the flowers. One likely candidate is the butterfly Pieris rapae (Cabbage White), which is originally from Europe. The foliage of plants in the Gentian family is usually bitter and unattractive to most herbivores, although rabbits may nibble on the stems and leaves of Branching Centaury occasionally. The seeds are too small to be of much interest to birds.
Photographic Location: A moist grassy depression that was located a short distance away from a railroad in Urbana, Illinois. This area was mowed irregularly and prone to temporary flooding.
Comments: Branching Centaury is a small plant with delicate pink flowers. It has many characteristics in common with members of the Pink family (Caryophyllaceae), but it differs in having a calyx with long slender lobes that are at least half the length of the tubular corolla. According to official records, this is the only Centaurium sp. that has naturalized in Illinois. Some south-central and southwestern states have native Centaurium spp., but none of them have been observed in Illinois. These native species tend to have somewhat larger flowers and more narrow lower leaves. A closely related species from Europe, the biennial Centaurium erythraea (Forking Centaury), has been observed in Indiana and may occur somewhere in Illinois. The inflorescence of this latter species is less flat-headed and more vertical, while its flowers have shorter calyx lobes and slightly longer corolla lobes. The Centaurium spp. differ from the closely related Sabatia spp. (Rose Pinks) by having smaller flowers that are longer than they are across; they are always narrowly tubular at the base. The flowers of Rose Pinks have more open corollas with larger petal-like lobes, while the lobes of their calyxes are more spreading.
Cultivation: Typical growing conditions are full sun and a moist soil that contains loam, clay-loam, or gravelly material. A limy soil and occasional flooding are tolerated.
Range & Habitat: Branching Centaury is an uncommon plant that is originally from Europe. It occurs primarily in a few counties in NE Illinois and does not appear to be spreading (see Distribution Map). The webmaster recently found a small colony of plants growing in Champaign County, Illinois. Habitats include moist depressions in grassy areas along roads and railroads. So far, this species is restricted to highly disturbed habitats.
Faunal Associations: Little information about floral-faunal relationships is available for this species. The structure of the flowers suggests that long-tongued bees, small butterflies, and skippers occasionally pollinate the flowers. One likely candidate is the butterfly Pieris rapae (Cabbage White), which is originally from Europe. The foliage of plants in the Gentian family is usually bitter and unattractive to most herbivores, although rabbits may nibble on the stems and leaves of Branching Centaury occasionally. The seeds are too small to be of much interest to birds.
Photographic Location: A moist grassy depression that was located a short distance away from a railroad in Urbana, Illinois. This area was mowed irregularly and prone to temporary flooding.
Comments: Branching Centaury is a small plant with delicate pink flowers. It has many characteristics in common with members of the Pink family (Caryophyllaceae), but it differs in having a calyx with long slender lobes that are at least half the length of the tubular corolla. According to official records, this is the only Centaurium sp. that has naturalized in Illinois. Some south-central and southwestern states have native Centaurium spp., but none of them have been observed in Illinois. These native species tend to have somewhat larger flowers and more narrow lower leaves. A closely related species from Europe, the biennial Centaurium erythraea (Forking Centaury), has been observed in Indiana and may occur somewhere in Illinois. The inflorescence of this latter species is less flat-headed and more vertical, while its flowers have shorter calyx lobes and slightly longer corolla lobes. The Centaurium spp. differ from the closely related Sabatia spp. (Rose Pinks) by having smaller flowers that are longer than they are across; they are always narrowly tubular at the base. The flowers of Rose Pinks have more open corollas with larger petal-like lobes, while the lobes of their calyxes are more spreading.
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Miss Chen
2018年07月30日
Description: This herbaceous plant is a summer annual (in Illinois) that forms a low rosette during the spring, but by summer it bolts to become 1-4' tall. A typical plant is unbranched below and branched above with ascending lateral stems. The stems are light green to light yellowish tan, terete, glabrous, and stiff. Alternate leaves occur at intervals along these stems. These leaves are 2-6" long, ½-2" across, and stiff; they are lanceolate, lanceolate-oblong, ovate, or ovate-oblong in shape. The leaf bases are sessile or they clasp the stems. Leaf margins are mostly smooth (entire) with scattered yellow spines, although lower leaf margins are sometimes spineless and slightly dentate (although in some uncommon cultivars, all leaves may be spineless). Both the upper and lower surfaces of the leaves are dark green and glabrous; minute pubescence may occur along the lower surfaces of the central leaf veins.
Each upper stem terminates in 1-5 flowerheads. The flowerheads of each branch are usually clustered together on short peduncles. Each flowerhead is ¾-1½" across (excluding the outer phyllaries), consisting of 20-100 disk florets. These florets are ¾-1" in length, although their bases are hidden from view. The corollas of these florets are yellow to red (rarely white), narrowly cylindrical below, and 5-lobed above; these lobes are linear in shape and spreading. The styles are strongly exerted from the corollas. Around the base of the flowerhead, there are several outer phyllaries (floral bracts) up to 1½" long that are widely spreading and stiff; they are elliptic or lanceolate in shape, while their margins are smooth (entire) with scattered yellow spines. The surfaces of these outer bracts are dark green and glabrous. The inner phyllaries are mostly erect and appressed together; they are light green, ovate or lanceolate in shape, and covered with appressed hairs. The margins of the inner phyllaries are mostly smooth (entire) and ciliate, although their tips are spiny. However, in some uncommon cultivars, both outer and inner phyllaries are spineless. The blooming period occurs from mid-spring into the fall (in Illinois), lasting about 1-3 months. Afterwards, fertile florets are replaced by achenes. The achenes are 6-8 mm. long, white or light brown, oblanceoloid in shape, bluntly 4-angled, and often longitudinally striped. Usually the apices of these achenes lack tufts of hair, although in some uncommon cultivars short stiff bristles are present. The root system consists of a stout taproot up to 3-4' long and some lateral roots. This plant reproduces by reseeding itself.
Cultivation: Safflower adapts to full sun, mesic to dry conditions, and various kinds of soil, including those that contain loam, sandy loam, or clay-loam. It prefers cool to warm temperatures while in the rosette stage, and warm to hot temperatures after it bolts (a warm-temperate zone with long summer days, a long growing season, and adequate rainfall prior to the blooming period). In areas with high humidity or cool weather during the summer, this plant is vulnerable to a variety of fungal disease organisms. Because of the deep taproot, resistance to heat and drought is excellent.
Range & Habitat: The non-native Safflower uncommonly naturalizes in Illinois, occurring in Champaign County (see Distribution Map). However, the presence of this species within the state is probably under-reported. Because of its preference for areas with relatively low humidity, Safflower is cultivated primarily in the western half of the United States, where it more frequently naturalizes. In the eastern half of the United States (including Illinois), naturalized plants are typically found around bird feeders as Safflower is sometimes used as a source of bird seed. Naturalized plants can occur after birds inadvertently drop the seeds, or spill the seeds from a bird feeder. As a result, typically habitats in Illinois are unmowed areas around bird feeders, including vegetable gardens, flowerbeds, open spaces near shrubbery, and edges of yards. However, these naturalized plants rarely persist from one year to the next. Safflower was introduced into the United States during the early 20th century as an agricultural crop (as a source of vegetable oil and a dye for clothing or food). This plant is probably native to the eastern Mediterranean region and parts of southern and central Asia, where it has been cultivated for thousands of years.
Faunal Associations: Little specific information is available for the floral-faunal relationships of Safflower in North America. The flowers are cross-pollinated by bumblebees, honeybees, other long-tongued bees, and probably other insects with long mouth parts (e.g., butterflies & skippers). However, in the absence of cross-pollination, the flowers are self-fertile. Seed bugs (Lygus), aphids, leafhoppers, thrips, wireworms, and the larvae of some moths are reported to feed destructively on Safflower. Among vertebrate animals, some songbirds (e.g., Cardinals) and probably upland gamebrids feed on the seeds, which are sometimes used as a source of food in bird feeders. Prior to the blooming period, the foliage of Safflower is reportedly edible to sheep and, to a lesser extent, cattle. The suitability of the foliage as a source of forage depends in part on its level of spininess; this varies with different cultivars.
Photographic Location: A mulched bed near some shrubbery at the Anita Purves Nature Center in Urbana, Illinois.
Comments: Safflower is grown primarily as an agricultural crop in the western half of the United States and other parts of the world. The flowerheads are a source of red and yellow dyes for clothing and food (now largely replaced by synthetic dyes), while vegetable oil is derived from its seeds. Safflower oil is high in oleic and linoleic fatty acids, and it is used as a source for cooking oil, salad oil, industrial oil, biodiesel fuel, margarine, soap, cosmetics, oil-based paints, and varnishes. Roasted or fried hulled seeds are edible to humans, while unhulled raw seeds are used as a source of food for birds. Young foliage and meal from processed seeds are edible to livestock (e.g., cattle & sheep). The primary advantage of Safflower over other agricultural crops is its ability to adapt to hot dry climates. Because of the spines on its foliage and floral bracts, Safflower resembles thistles (Cirsium spp., Carduus spp.), but the corollas of its flowerheads are yellow to red, rather than pink or purple. Unlike thistles, the achenes of Safflower lack tufts of hair at their apices, except for some uncommon cultivars that have achenes with short bristles. In addition, the widely spreading and spiny floral bracts of Safflower have a distinctive appearance.
Each upper stem terminates in 1-5 flowerheads. The flowerheads of each branch are usually clustered together on short peduncles. Each flowerhead is ¾-1½" across (excluding the outer phyllaries), consisting of 20-100 disk florets. These florets are ¾-1" in length, although their bases are hidden from view. The corollas of these florets are yellow to red (rarely white), narrowly cylindrical below, and 5-lobed above; these lobes are linear in shape and spreading. The styles are strongly exerted from the corollas. Around the base of the flowerhead, there are several outer phyllaries (floral bracts) up to 1½" long that are widely spreading and stiff; they are elliptic or lanceolate in shape, while their margins are smooth (entire) with scattered yellow spines. The surfaces of these outer bracts are dark green and glabrous. The inner phyllaries are mostly erect and appressed together; they are light green, ovate or lanceolate in shape, and covered with appressed hairs. The margins of the inner phyllaries are mostly smooth (entire) and ciliate, although their tips are spiny. However, in some uncommon cultivars, both outer and inner phyllaries are spineless. The blooming period occurs from mid-spring into the fall (in Illinois), lasting about 1-3 months. Afterwards, fertile florets are replaced by achenes. The achenes are 6-8 mm. long, white or light brown, oblanceoloid in shape, bluntly 4-angled, and often longitudinally striped. Usually the apices of these achenes lack tufts of hair, although in some uncommon cultivars short stiff bristles are present. The root system consists of a stout taproot up to 3-4' long and some lateral roots. This plant reproduces by reseeding itself.
Cultivation: Safflower adapts to full sun, mesic to dry conditions, and various kinds of soil, including those that contain loam, sandy loam, or clay-loam. It prefers cool to warm temperatures while in the rosette stage, and warm to hot temperatures after it bolts (a warm-temperate zone with long summer days, a long growing season, and adequate rainfall prior to the blooming period). In areas with high humidity or cool weather during the summer, this plant is vulnerable to a variety of fungal disease organisms. Because of the deep taproot, resistance to heat and drought is excellent.
Range & Habitat: The non-native Safflower uncommonly naturalizes in Illinois, occurring in Champaign County (see Distribution Map). However, the presence of this species within the state is probably under-reported. Because of its preference for areas with relatively low humidity, Safflower is cultivated primarily in the western half of the United States, where it more frequently naturalizes. In the eastern half of the United States (including Illinois), naturalized plants are typically found around bird feeders as Safflower is sometimes used as a source of bird seed. Naturalized plants can occur after birds inadvertently drop the seeds, or spill the seeds from a bird feeder. As a result, typically habitats in Illinois are unmowed areas around bird feeders, including vegetable gardens, flowerbeds, open spaces near shrubbery, and edges of yards. However, these naturalized plants rarely persist from one year to the next. Safflower was introduced into the United States during the early 20th century as an agricultural crop (as a source of vegetable oil and a dye for clothing or food). This plant is probably native to the eastern Mediterranean region and parts of southern and central Asia, where it has been cultivated for thousands of years.
Faunal Associations: Little specific information is available for the floral-faunal relationships of Safflower in North America. The flowers are cross-pollinated by bumblebees, honeybees, other long-tongued bees, and probably other insects with long mouth parts (e.g., butterflies & skippers). However, in the absence of cross-pollination, the flowers are self-fertile. Seed bugs (Lygus), aphids, leafhoppers, thrips, wireworms, and the larvae of some moths are reported to feed destructively on Safflower. Among vertebrate animals, some songbirds (e.g., Cardinals) and probably upland gamebrids feed on the seeds, which are sometimes used as a source of food in bird feeders. Prior to the blooming period, the foliage of Safflower is reportedly edible to sheep and, to a lesser extent, cattle. The suitability of the foliage as a source of forage depends in part on its level of spininess; this varies with different cultivars.
Photographic Location: A mulched bed near some shrubbery at the Anita Purves Nature Center in Urbana, Illinois.
Comments: Safflower is grown primarily as an agricultural crop in the western half of the United States and other parts of the world. The flowerheads are a source of red and yellow dyes for clothing and food (now largely replaced by synthetic dyes), while vegetable oil is derived from its seeds. Safflower oil is high in oleic and linoleic fatty acids, and it is used as a source for cooking oil, salad oil, industrial oil, biodiesel fuel, margarine, soap, cosmetics, oil-based paints, and varnishes. Roasted or fried hulled seeds are edible to humans, while unhulled raw seeds are used as a source of food for birds. Young foliage and meal from processed seeds are edible to livestock (e.g., cattle & sheep). The primary advantage of Safflower over other agricultural crops is its ability to adapt to hot dry climates. Because of the spines on its foliage and floral bracts, Safflower resembles thistles (Cirsium spp., Carduus spp.), but the corollas of its flowerheads are yellow to red, rather than pink or purple. Unlike thistles, the achenes of Safflower lack tufts of hair at their apices, except for some uncommon cultivars that have achenes with short bristles. In addition, the widely spreading and spiny floral bracts of Safflower have a distinctive appearance.
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Miss Chen
2018年07月26日
Description: This plant is a winter annual or biennial that becomes ½–2' tall, branching very little except at the base. The round stems are more or less hairy. The alternate leaves are up to 1½" long and ¼" across. They are oblanceolate, lanceolate-oblong, or oblong-linear, and sessile at the base. The upper surface of each leaf has a single central vein, but radiating side veins are not visible. The leaves are more or less pubescent, although they occasionally have longer white hairs. Their margins are smooth and ciliate.
The nearly sessile flowers develop from the axils of the leaves in the upper portion of the stems. They are bunched together while in bloom or at the bud stage, but become more separated from each other as the flowering stems continue to elongate. Each flower is about ¼" long, consisting of a tubular white corolla with 5 small lobes and a hairy green calyx with 5 teeth that are linear-lanceolate. These teeth are about as long as the corolla. There are 5 stamens and a pistil that are inserted within the narrow throat of the corolla. The blooming period can occur from mid-spring to mid-summer and lasts about 2 months. Each flower is replaced by 4 nutlets. A nutlet is truncate at the base and tapers to a blunt round tip at the top. It is broadest a little below the middle, and has a greyish brown surface that is rough and wrinkled. The root system consists of a taproot. This plant spreads by reseeding itself.
Cultivation: This adaptable plant can be found in full or partial sun and mesic conditions in fertile loam, clay-loam, or sandy soil. Open areas are preferred where there is a scarcity of taller plants.
Close-up of FlowersRange & Habitat: Corn Gromwell is occasional to locally common in most areas of Illinois, except in the NW and SE, where it is uncommon or absent (see Distribution Map). It is adventive in North America and native to Eurasia. Habitats include cropland consisting of winter wheat or rye, fallow fields, vacant lots, grassy areas along roadsides and railroads, and miscellaneous waste areas. This weed occurs primarily in fields or along railroads, but it also appears in run-down areas of cities. Corn Gromwell prefers disturbed areas, and doesn't invade high quality natural sites to any significant degree.
Faunal Associations: Little information is available about floral-faunal relations for this species. According to Muller of 19th century Germany, the flowers of Corn Gromwell have few insect visitors. Occasionally, they attracted White butterflies, bees, and Syrphid flies.
Photographic Location: A grassy vacant lot in Urbana, Illinois.
Comments: This is a rather inconspicuous plant even while it is blooming. Corn Gromwell resembles many other weeds with small white flowers, but it has a distinguishing characteristic that sets it apart: The teeth of the hairy calyx are unusually long, slender, and conspicuous – about the same length as the flowers. Long after the corolla of a flower has withered away, the teeth of the calyx surround the nutlets on all sides and are much taller than them. Corn Gromwell resembles other members of the Borage family to some extent, including the native Lithospermum latifolium (American Gromwell) and introduced Lithospermum officinale (European Gromwell). However, these latter species have wider leaves with conspicuous side veins. Corn Gromwell is easily distinguished from the many weedy members of the Mustard family because its tubular flowers have 5 petal-like lobes, while the flowers of the latter have only 4 petals. An obsolete scientific name for this plant is Lithospermum arvense.
The nearly sessile flowers develop from the axils of the leaves in the upper portion of the stems. They are bunched together while in bloom or at the bud stage, but become more separated from each other as the flowering stems continue to elongate. Each flower is about ¼" long, consisting of a tubular white corolla with 5 small lobes and a hairy green calyx with 5 teeth that are linear-lanceolate. These teeth are about as long as the corolla. There are 5 stamens and a pistil that are inserted within the narrow throat of the corolla. The blooming period can occur from mid-spring to mid-summer and lasts about 2 months. Each flower is replaced by 4 nutlets. A nutlet is truncate at the base and tapers to a blunt round tip at the top. It is broadest a little below the middle, and has a greyish brown surface that is rough and wrinkled. The root system consists of a taproot. This plant spreads by reseeding itself.
Cultivation: This adaptable plant can be found in full or partial sun and mesic conditions in fertile loam, clay-loam, or sandy soil. Open areas are preferred where there is a scarcity of taller plants.
Close-up of FlowersRange & Habitat: Corn Gromwell is occasional to locally common in most areas of Illinois, except in the NW and SE, where it is uncommon or absent (see Distribution Map). It is adventive in North America and native to Eurasia. Habitats include cropland consisting of winter wheat or rye, fallow fields, vacant lots, grassy areas along roadsides and railroads, and miscellaneous waste areas. This weed occurs primarily in fields or along railroads, but it also appears in run-down areas of cities. Corn Gromwell prefers disturbed areas, and doesn't invade high quality natural sites to any significant degree.
Faunal Associations: Little information is available about floral-faunal relations for this species. According to Muller of 19th century Germany, the flowers of Corn Gromwell have few insect visitors. Occasionally, they attracted White butterflies, bees, and Syrphid flies.
Photographic Location: A grassy vacant lot in Urbana, Illinois.
Comments: This is a rather inconspicuous plant even while it is blooming. Corn Gromwell resembles many other weeds with small white flowers, but it has a distinguishing characteristic that sets it apart: The teeth of the hairy calyx are unusually long, slender, and conspicuous – about the same length as the flowers. Long after the corolla of a flower has withered away, the teeth of the calyx surround the nutlets on all sides and are much taller than them. Corn Gromwell resembles other members of the Borage family to some extent, including the native Lithospermum latifolium (American Gromwell) and introduced Lithospermum officinale (European Gromwell). However, these latter species have wider leaves with conspicuous side veins. Corn Gromwell is easily distinguished from the many weedy members of the Mustard family because its tubular flowers have 5 petal-like lobes, while the flowers of the latter have only 4 petals. An obsolete scientific name for this plant is Lithospermum arvense.
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Miss Chen
2018年07月26日
Description: This plant is an annual or biennial about 1-3' tall. Small plants are branched sparingly, while large plants branch abundantly in the upper half. The stems are gray-green or gray-blue, terete, glabrous, and glaucous. Plants that begin growth during the fall will overwinter as low rosettes with basal leaves, while plants that begin growth during the spring bolt upward almost immediately. Both the basal and lower leaves are up to 10" long and 2" across, but they are usually smaller than this. They are oblanceolate in overall shape and strongly pinnatifid with undulate or bluntly dentate margins; their terminal lobes are the largest in size. Both types of leaves have stout petioles. In contrast, the middle to upper leaves are smaller in size, lanceolate-oblong in shape, with margins that are smooth or bluntly dentate. These latter leaves have bases that usually clasp their stems, although some of them may be sessile. Like the stems, these various leaves are grey-green or blue-green, glaucous, and usually glabrous – occasionally the basal leaves have short bristly hairs. The lower, middle, and upper leaves are alternate.
The upper stems terminate in racemes of bright yellow flowers. The flowers bloom toward the apex of each raceme, while the seedpods develop below. Each flower is 1/3–1/2" (8-12 mm.) across, consisting of 4 yellow petals, 4 green to yellow sepals, several stamens, and a pistil with a single style. The sepals are narrowly lanceolate and hairless. The blooming period can occur anytime between late spring to early fall; it usually lasts about 1 month for a small colony of plants. Each flower is replaced by an ascending cylindrical seedpod (silique) that is 1¼–2¼" long at maturity and hairless. Each seedpod terminates in a seedless beak that is about one-fourth its entire length. At the base of each seedpod, there is a stout hairless pedicel about ½" long that is widely spreading to ascending. Each seedpod divides into 2 valves to release its small globoid seeds. The root system consists of a taproot. This plant reproduces by reseeding itself.
Cultivation: Rape Mustard prefers full sunlight, moist to dry conditions, and a neutral to alkaline soil containing loam, clay-loam, or gravelly material. The size of individual plants varies greatly according to moisture conditions and soil fertility.
Range & Habitat: Rape Mustard is occasional in most areas of Illinois (see Distribution Map). It is native to Eurasia. Typical habitats include cropland, weedy fields, roadsides, gravelly areas along railroads, and waste areas. This plant is usually found in areas with a history of disturbance where there is scant ground vegetation.
Faunal Associations: The nectar of the flowers attracts small bees and White butterflies (Pieridae); some bees may collect pollen from the flowers as well. The caterpillars of the butterflies Pieris napi (Mustard White), Pieris rapae (Cabbage White), and Pontia protodice (Checkered White) feed on Brassica spp. (Mustards), as do the caterpillars of the moths Evergestis pallidata (Purple-Backed Cabbageworm) and Plutella xylostella (Diamondback Moth). Several species of flea beetles (primarily Phyllotreta spp.), Murgantia histrionica (Harlequin Bug), and Adelphocoris superbus (Meadow Plant Bug) also feed on the foliage of these plants. The oily seeds of Rape Mustard and similar species are eaten by the Mourning Dove and Ring-Necked Pheasant, and the mild-tasting foliage can be eaten in limited amounts by livestock and other mammalian herbivores.
Photographic Location: A gravelly area along a railroad in Savoy, Illinois.
Comments: This is another weedy mustard species from Eurasia. It should not be confused with the agricultural crop, Oilseed Rape (or Canola), which is Brassica napus oleifera, or one of the cultivated vegetables. Rape Mustard has several common names, including Field Mustard and Birdseed Rape. In general, Rape Mustard can be distinguished from other Brassica spp. (Mustards) by its glaucous gray-blue or gray-green foliage and its clasping alternate leaves. A similar species, Brassica oleracea (Wild Cabbage), shares these characteristics, but this latter species has larger flowers (exceeding ½" across) and it is quite rare in Illinois. Oilseed Rape has foliage that is more green than either Rape Mustard or Wild Cabbage, and its foliage isn't glaucous.
The upper stems terminate in racemes of bright yellow flowers. The flowers bloom toward the apex of each raceme, while the seedpods develop below. Each flower is 1/3–1/2" (8-12 mm.) across, consisting of 4 yellow petals, 4 green to yellow sepals, several stamens, and a pistil with a single style. The sepals are narrowly lanceolate and hairless. The blooming period can occur anytime between late spring to early fall; it usually lasts about 1 month for a small colony of plants. Each flower is replaced by an ascending cylindrical seedpod (silique) that is 1¼–2¼" long at maturity and hairless. Each seedpod terminates in a seedless beak that is about one-fourth its entire length. At the base of each seedpod, there is a stout hairless pedicel about ½" long that is widely spreading to ascending. Each seedpod divides into 2 valves to release its small globoid seeds. The root system consists of a taproot. This plant reproduces by reseeding itself.
Cultivation: Rape Mustard prefers full sunlight, moist to dry conditions, and a neutral to alkaline soil containing loam, clay-loam, or gravelly material. The size of individual plants varies greatly according to moisture conditions and soil fertility.
Range & Habitat: Rape Mustard is occasional in most areas of Illinois (see Distribution Map). It is native to Eurasia. Typical habitats include cropland, weedy fields, roadsides, gravelly areas along railroads, and waste areas. This plant is usually found in areas with a history of disturbance where there is scant ground vegetation.
Faunal Associations: The nectar of the flowers attracts small bees and White butterflies (Pieridae); some bees may collect pollen from the flowers as well. The caterpillars of the butterflies Pieris napi (Mustard White), Pieris rapae (Cabbage White), and Pontia protodice (Checkered White) feed on Brassica spp. (Mustards), as do the caterpillars of the moths Evergestis pallidata (Purple-Backed Cabbageworm) and Plutella xylostella (Diamondback Moth). Several species of flea beetles (primarily Phyllotreta spp.), Murgantia histrionica (Harlequin Bug), and Adelphocoris superbus (Meadow Plant Bug) also feed on the foliage of these plants. The oily seeds of Rape Mustard and similar species are eaten by the Mourning Dove and Ring-Necked Pheasant, and the mild-tasting foliage can be eaten in limited amounts by livestock and other mammalian herbivores.
Photographic Location: A gravelly area along a railroad in Savoy, Illinois.
Comments: This is another weedy mustard species from Eurasia. It should not be confused with the agricultural crop, Oilseed Rape (or Canola), which is Brassica napus oleifera, or one of the cultivated vegetables. Rape Mustard has several common names, including Field Mustard and Birdseed Rape. In general, Rape Mustard can be distinguished from other Brassica spp. (Mustards) by its glaucous gray-blue or gray-green foliage and its clasping alternate leaves. A similar species, Brassica oleracea (Wild Cabbage), shares these characteristics, but this latter species has larger flowers (exceeding ½" across) and it is quite rare in Illinois. Oilseed Rape has foliage that is more green than either Rape Mustard or Wild Cabbage, and its foliage isn't glaucous.
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Miss Chen
2018年07月25日
Description: This plant is a summer annual that becomes 2-8' tall, branching occasionally. The stems are usually glabrous and glaucous; sometimes they have scattered stiff hairs toward the base. The alternate leaves are up to 10" long and 3" across, becoming smaller as they ascend the stems. The lower leaves are pinnately lobed and obovate in outline, tapering to a long and rather stout petiole. The terminal lobe is much larger than the lateral lobes. The upper surface of a lower leaf is often bristly with scattered hairs that are stiff, short, and white. The lower surface is usually glabrous, except for a few hairs along the central vein. The upper leaves are often lanceolate, broadly elliptic, or some other odd shape; they have 1-2 lobes or none.
The upper stems terminate in narrow racemes of yellow flowers; these racemes are ½–2' long when fully mature. Each flower is up to 1/3" (8 mm.) across, consisting of 4 yellow petals, 4 sepals, several stamens, and a pistil. The sepals are initially green, but become yellow while the flower blooms. The petals are well-rounded toward their tips. The blooming period occurs primarily during the summer and lasts about 1-2 months. A few plants may bloom during the fall. Each flower is replaced by a slender silique that becomes appressed against the stalk of the raceme as it matures. This silique is about 2/3" (17 mm.) long, tapering to a conical beak. The petiole of the silique (or flower) is about 1/3" (8 mm.) long. The seeds within this silique are dark brown or black. Both the seeds and the foliage have a pungent taste. The root system consists of a taproot. This plant spreads by reseeding itself.
Cultivation: This plant often occurs in full or partial sun, fertile soil, and mesic conditions. On less fertile ground, it is smaller in size. During hot sunny weather the leaves have a tendency to wilt, but they quickly recover by nightfall. Sometimes this plant becomes lanky and flops sideways.
Range & Habitat: The non-native Black Mustard is a common plant in central and northern Illinois, but it is less common or absent in southern Illinois (see Distribution Map). Habitats include weedy meadows, thickets, areas along railroads and roadsides, fallow fields, vacant lots, and miscellaneous waste places. Disturbed areas are preferred; Black Mustard doesn't invade high quality natural areas to any significant degree. It is native to Eurasia.
Faunal Associations: The nectar and pollen of the flowers attract primarily small bees and flower flies; less common visitors include White butterflies and wasps. The foliage is occasionally eaten by the caterpillars of various White butterflies, including Pieris rapae (Cabbage White) and Pontia protodice (Checkered White). The pungent foliage is usually avoided by mammalian herbivores; it is somewhat toxic to them.
Photographic Location: Along a railroad in a partially shaded area in Urbana, Illinois.
Comments: If you see a lanky mustard plant with narrow stalks of yellow flowers that is over your head, there's a good chance that it's Black Mustard. The seeds of Black Mustard are often used in the table condiment, hot mustard. Among the many Brassica spp. and Synapis spp. (Mustards), Black Mustard can be identified by considering the following characteristics: 1) It is often quite tall, 2) the slender siliques are appressed together near the stalk of each raceme, 3) the siliques are less than ¾" long and they have distinct beaks, 4) the leaves narrowly clasp the stems, 5) the terminal lobes of the lower leaves are much larger than the lateral lobes, and 6) the lower leaves often have short stiff hairs and feel bristly to the touch. Other mustards are often lacking one or more of these features.
The upper stems terminate in narrow racemes of yellow flowers; these racemes are ½–2' long when fully mature. Each flower is up to 1/3" (8 mm.) across, consisting of 4 yellow petals, 4 sepals, several stamens, and a pistil. The sepals are initially green, but become yellow while the flower blooms. The petals are well-rounded toward their tips. The blooming period occurs primarily during the summer and lasts about 1-2 months. A few plants may bloom during the fall. Each flower is replaced by a slender silique that becomes appressed against the stalk of the raceme as it matures. This silique is about 2/3" (17 mm.) long, tapering to a conical beak. The petiole of the silique (or flower) is about 1/3" (8 mm.) long. The seeds within this silique are dark brown or black. Both the seeds and the foliage have a pungent taste. The root system consists of a taproot. This plant spreads by reseeding itself.
Cultivation: This plant often occurs in full or partial sun, fertile soil, and mesic conditions. On less fertile ground, it is smaller in size. During hot sunny weather the leaves have a tendency to wilt, but they quickly recover by nightfall. Sometimes this plant becomes lanky and flops sideways.
Range & Habitat: The non-native Black Mustard is a common plant in central and northern Illinois, but it is less common or absent in southern Illinois (see Distribution Map). Habitats include weedy meadows, thickets, areas along railroads and roadsides, fallow fields, vacant lots, and miscellaneous waste places. Disturbed areas are preferred; Black Mustard doesn't invade high quality natural areas to any significant degree. It is native to Eurasia.
Faunal Associations: The nectar and pollen of the flowers attract primarily small bees and flower flies; less common visitors include White butterflies and wasps. The foliage is occasionally eaten by the caterpillars of various White butterflies, including Pieris rapae (Cabbage White) and Pontia protodice (Checkered White). The pungent foliage is usually avoided by mammalian herbivores; it is somewhat toxic to them.
Photographic Location: Along a railroad in a partially shaded area in Urbana, Illinois.
Comments: If you see a lanky mustard plant with narrow stalks of yellow flowers that is over your head, there's a good chance that it's Black Mustard. The seeds of Black Mustard are often used in the table condiment, hot mustard. Among the many Brassica spp. and Synapis spp. (Mustards), Black Mustard can be identified by considering the following characteristics: 1) It is often quite tall, 2) the slender siliques are appressed together near the stalk of each raceme, 3) the siliques are less than ¾" long and they have distinct beaks, 4) the leaves narrowly clasp the stems, 5) the terminal lobes of the lower leaves are much larger than the lateral lobes, and 6) the lower leaves often have short stiff hairs and feel bristly to the touch. Other mustards are often lacking one or more of these features.
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Miss Chen
2018年07月25日
Description: This annual wildflower is 1½–2½' tall, branching occasionally. The stems are light to medium green, terete, hollow, and densely covered with stiff white hairs. Alternate leaves along these stems are 2-6" long and about one-third as much across; they are ovate, obovate, or oblanceolate in shape with margins that are smooth and slightly undulate. The upper leaf surface is dark green, wrinkled from indented veins, and covered with sparse appressed hairs. The lower leaf surface is light to medium green and hairy primarily along the undersides of the veins.
Upper stems terminate in scorpioid cymes of nodding flowers. Individual flowers are ¾-1" across, consisting of 5 lanceolate blue petals (rarely white or pink), 5 green sepals, 5 dark blue to black anthers that merge together to form a central beak, and an ovary with a single style. The linear sepals are covered with stiff white hairs along their outer surfaces; they are about the same length or a little shorter than the petals. Like the stems and sepals, the branches of each inflorescence are covered with stiff white hairs; they are green to dark red. In Illinois, the blooming period occurs from mid-summer into the fall, lasting about 1½-3 months. Each flower is replaced by 4 dark brown nutlets. The root system consists of a taproot. This wildflower spreads by reseeding itself.
Cultivation: The preference is a sunny position, mesic conditions, and a fertile loamy soil.
Range & Habitat: Borage has naturalized in only a few counties in Illinois (see Distribution Map). Naturalized populations rarely persist for more than a few years. Borage was introduced into North America from Europe as an herbal and ornamental plant; it is native to the Mediterranean area. Habitats consist of areas near buildings, rubbish heaps consisting of organic material, and waste areas. Borage is still cultivated in gardens.
Faunal Associations: According to Muëller (1873/1883), the nectar and pollen of the flowers attract bees, including honeybees, bumblebees, other long-tongued bees, and Halictid bees. It is unclear to what extent mammalian herbivores in North America feed on the foliage of Borage, which is mildly toxic from the presence of pyrrolizidine alkaloids. Similarly, there is lack of information about the consumption of seeds by birds and rodents.
Photographic Location: An herbal garden at Meadowbrook Park in Urbana, Illinois.
Comments: The most striking aspect of this plant are the star-shaped flowers; the petals have a shade of genuine blue that is uncommon among flowering plants. The flowers are reportedly edible with a sweet taste. The leaves are also eaten in salads and other dishes; they have a cucumber-like flavor. However, because of their potential toxicity, the leaves should be eaten in only small amounts. Because of its unique blue flowers, Borage is easy to identify. Other species in the Borage family have flowers with more conventional corollas.
Upper stems terminate in scorpioid cymes of nodding flowers. Individual flowers are ¾-1" across, consisting of 5 lanceolate blue petals (rarely white or pink), 5 green sepals, 5 dark blue to black anthers that merge together to form a central beak, and an ovary with a single style. The linear sepals are covered with stiff white hairs along their outer surfaces; they are about the same length or a little shorter than the petals. Like the stems and sepals, the branches of each inflorescence are covered with stiff white hairs; they are green to dark red. In Illinois, the blooming period occurs from mid-summer into the fall, lasting about 1½-3 months. Each flower is replaced by 4 dark brown nutlets. The root system consists of a taproot. This wildflower spreads by reseeding itself.
Cultivation: The preference is a sunny position, mesic conditions, and a fertile loamy soil.
Range & Habitat: Borage has naturalized in only a few counties in Illinois (see Distribution Map). Naturalized populations rarely persist for more than a few years. Borage was introduced into North America from Europe as an herbal and ornamental plant; it is native to the Mediterranean area. Habitats consist of areas near buildings, rubbish heaps consisting of organic material, and waste areas. Borage is still cultivated in gardens.
Faunal Associations: According to Muëller (1873/1883), the nectar and pollen of the flowers attract bees, including honeybees, bumblebees, other long-tongued bees, and Halictid bees. It is unclear to what extent mammalian herbivores in North America feed on the foliage of Borage, which is mildly toxic from the presence of pyrrolizidine alkaloids. Similarly, there is lack of information about the consumption of seeds by birds and rodents.
Photographic Location: An herbal garden at Meadowbrook Park in Urbana, Illinois.
Comments: The most striking aspect of this plant are the star-shaped flowers; the petals have a shade of genuine blue that is uncommon among flowering plants. The flowers are reportedly edible with a sweet taste. The leaves are also eaten in salads and other dishes; they have a cucumber-like flavor. However, because of their potential toxicity, the leaves should be eaten in only small amounts. Because of its unique blue flowers, Borage is easy to identify. Other species in the Borage family have flowers with more conventional corollas.
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Miss Chen
2018年07月25日
Description: This plant is a summer annual about 2-5' tall; it is more or less erect and branches occasionally. The stems are green or reddish green, angular, strongly veined, and hairless (or nearly so). The leaves are mostly opposite; their blades are up to 8" long and 4" across, while their petioles are up to 2" long. The leaf blades are double- or triple-pinnate, medium green, and hairless (or nearly so). The segments of the blades are ovate, lanceolate, or oblanceolate with blunt tips and wedge-shaped bottoms; the margins of these segments are irregularly cleft or dentate. Overall, the leaf blades have a fern-like appearance. The upper stems terminate in individual flowerheads on long peduncles. Each flowerhead is about ½" long and ¼" across; it has numerous disk florets in the center and 0-5 ray florets along its upper margin. The disk florets have corollas that are golden yellow and tubular in shape; each corolla has 5 tiny lobes along its upper rim. The yellow ray florets are petal-like; they are about 1/8" (3 mm.) long and oval to oblong in shape. Some flowerheads may lack petal-like extensions of the ray florets altogether. The base of the flowerhead is surrounded by green bracts; the linear inner bracts are much longer (about 1/3" or 8 mm. in length) than the outer bracts. The blooming period occurs during the late summer or early fall. Each flowerhead is replaced by a seedhead that is globoid in shape and spans about 1" across. The long narrow seeds (achenes) spread outward from the center in all directions. Each mature seed is linear in shape, 4-angled, and dark brown; it has 2-4 short awns at its tip. Each tiny awn has downward-pointed barbs. The root system consists of a branching taproot. This plant spreads by reseeding itself.
Cultivation: Partial or dappled sunlight, moist to mesic conditions, and a fertile loamy soil are preferred. However, this robust plant can adapt to a wide range of environmental conditions. The size of individual plants varies significantly, depending on moisture levels and soil fertility.
Range & Habitat: The native Spanish Needles is occasional to locally common in southern and central Illinois; it is mostly absent in the northern section of the state (see Distribution Map). Habitats include open woodlands, woodland borders, savannas, thickets, rocky glades, riverbanks, weedy meadows, vacant lots, partially shaded areas along buildings, areas along railroads and roadsides, abandoned fields, and waste areas. Habitats with a history of disturbance are preferred. In Illinois, Spanish Needles is more often found in drier habitats than other species in the genus.
Faunal Associations: The nectar and pollen of the flowerheads attract bees: these include honeybees, leaf-cutting bees (Megachile spp., Coelioxys sayi, & Heriades leavitti), and Halictid bees (including green metallic bees). Other insect visitors of the flowers include Syrphid flies and the butterfly Pieris rapae (Cabbage White). Rather then visiting the flowers, other insects feed on the foliage and other parts of Bidens spp. These species include the caterpillars of the moths Cirrhophanus triangulifer (Goldenrod Stowaway), Condica confederata (The Confederate), Epiblema otiosana (Bidens Borer Moth), Palthis asopialis (Fainted-Spotted Palthis), Platysenta mobilis (Mobile Groundling), and Synchlora aerata (Wavy-Lined Emerald). The leaf beetles Calligrapha bidenticola and Calligrapha californica feed on the leaves of Bidens spp., while the aphid Aphis coreopsidis sucks juices from the flowering stalks. Many of these insects feed on similar plants in the Aster family. Seeds of Bidens spp. are eaten to a minor extent by various birds, including the Ring-Necked Pheasant, Bobwhite, Wood Duck, Purple Finch, and Common Redpoll. The foliage is sometimes eaten by the Cottontail Rabbit. The barbed awns of the seeds can cling to the fur of passing animals and the clothing of humans; in this manner, the seeds are distributed far and wide.
Photographic Location: The photographs were taken at a small grove of trees along a railroad in Champaign, Illinois, and a vacant lot in Urbana, Illinois. In one photograph, a green metallic bee is visiting a flowerhead. Underneath this flowerhead, there are some greenish aphids sucking juices from the stalk, although they are difficult to see.
Comments: The arrangement of the trident-shaped seeds into globoid seedheads is very striking. The common name derives from the appearance of these seeds. Among the many Bidens spp. in Illinois, Spanish Needles is the oddball of the group. The seeds of Spanish Needles are longer and usually more slender than those of other Bidens spp. Spanish Needles also has differently shaped leaves – they are more pinnately divided into smaller leaf segments than the leaves of other Bidens spp. (which are sometimes simple, rather than compound). Finally, Spanish Needles seems to prefer drier habitats; other Bidens spp. are more likely to be found in various wetland habitats.
Cultivation: Partial or dappled sunlight, moist to mesic conditions, and a fertile loamy soil are preferred. However, this robust plant can adapt to a wide range of environmental conditions. The size of individual plants varies significantly, depending on moisture levels and soil fertility.
Range & Habitat: The native Spanish Needles is occasional to locally common in southern and central Illinois; it is mostly absent in the northern section of the state (see Distribution Map). Habitats include open woodlands, woodland borders, savannas, thickets, rocky glades, riverbanks, weedy meadows, vacant lots, partially shaded areas along buildings, areas along railroads and roadsides, abandoned fields, and waste areas. Habitats with a history of disturbance are preferred. In Illinois, Spanish Needles is more often found in drier habitats than other species in the genus.
Faunal Associations: The nectar and pollen of the flowerheads attract bees: these include honeybees, leaf-cutting bees (Megachile spp., Coelioxys sayi, & Heriades leavitti), and Halictid bees (including green metallic bees). Other insect visitors of the flowers include Syrphid flies and the butterfly Pieris rapae (Cabbage White). Rather then visiting the flowers, other insects feed on the foliage and other parts of Bidens spp. These species include the caterpillars of the moths Cirrhophanus triangulifer (Goldenrod Stowaway), Condica confederata (The Confederate), Epiblema otiosana (Bidens Borer Moth), Palthis asopialis (Fainted-Spotted Palthis), Platysenta mobilis (Mobile Groundling), and Synchlora aerata (Wavy-Lined Emerald). The leaf beetles Calligrapha bidenticola and Calligrapha californica feed on the leaves of Bidens spp., while the aphid Aphis coreopsidis sucks juices from the flowering stalks. Many of these insects feed on similar plants in the Aster family. Seeds of Bidens spp. are eaten to a minor extent by various birds, including the Ring-Necked Pheasant, Bobwhite, Wood Duck, Purple Finch, and Common Redpoll. The foliage is sometimes eaten by the Cottontail Rabbit. The barbed awns of the seeds can cling to the fur of passing animals and the clothing of humans; in this manner, the seeds are distributed far and wide.
Photographic Location: The photographs were taken at a small grove of trees along a railroad in Champaign, Illinois, and a vacant lot in Urbana, Illinois. In one photograph, a green metallic bee is visiting a flowerhead. Underneath this flowerhead, there are some greenish aphids sucking juices from the stalk, although they are difficult to see.
Comments: The arrangement of the trident-shaped seeds into globoid seedheads is very striking. The common name derives from the appearance of these seeds. Among the many Bidens spp. in Illinois, Spanish Needles is the oddball of the group. The seeds of Spanish Needles are longer and usually more slender than those of other Bidens spp. Spanish Needles also has differently shaped leaves – they are more pinnately divided into smaller leaf segments than the leaves of other Bidens spp. (which are sometimes simple, rather than compound). Finally, Spanish Needles seems to prefer drier habitats; other Bidens spp. are more likely to be found in various wetland habitats.
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Miss Chen
2018年07月24日
Description: This plant is a summer annual about 1½–3' long; it branches occasionally, especially near the base. The stems are erect, ascending, or sprawling (often the latter); they are light green, more or less white-mealy, and terete or angular. The larger stems often have white longitudinal veins. The lowest leaves are opposite, while the remaining leaves are alternate; they have slender petioles up to 1" long. The leaf blades are up to 3½" long and ¾" across, becoming gradually smaller as they ascend the stems; they are green, flat, and either smooth or slightly undulate along their margins. The leaf blades have different shapes, but they are usually lanceolate-ovate, lanceolate, or oblong-linear; some leaves may have 1 or 2 lobes toward the base of their blades. The upper surface of each blade is hairless or glabrous, while the lower surface is often white-mealy.
The upper stems terminate in spikes or spike-like panicles of flowers; axillary spikes also develop from some of the upper leaves. The flowers are arranged in sessile clusters along the spikes or the branches of the panicles. Common Orach is monoecious with separate male (staminate) and female (pistillate) flowers on the same plant. Each male flower has 5 sepals and 5 stamens; it is whitish green and about 1/8" (3 mm.) across. Each female flower has an ovary with 2 styles and a pair of small bracts at its base; it is green and about 1/8" (3 mm.) across. The male flowers lack petals, while the female flowers have neither petals nor sepals. The flowers and branches of each inflorescence are white-mealy. The blooming period occurs during late summer into the fall. Pollination is by wind. The bracts of the female flowers enlarge in size, becoming triangular-hastate in shape and about 1/5" (5 mm.) in length; they form a flattened fruit that encloses the developing seed. Mature seeds are flattened, circular, and shiny black; each seed is covered by a thin rough membrane that is difficult to remove. The root system consists of a branching taproot. This plant spreads by reseeding itself.
Cultivation: The preference is full sun to light shade, moist to mesic conditions, and a fertile loamy soil. Toleration of salty alkaline conditions is quite good, although in Illinois this species is usually found in ordinary garden soil.
Range & Habitat: The adventive Common Orach occurs occasionally in central and northern Illinois, while in the southern part of the state it is uncommon (see Distribution Map). This species is native to Eurasia and northern Africa. Habitats include woodland borders, gardens, edges of yards, unmowed areas around telephone poles and tree stumps, areas along railroads and roadsides, dumps, and waste areas. Areas with a history of disturbance are preferred. In Illinois, this species is not invasive of natural habitats.
Faunal Associations: Insects that feed primarily on the leaves of Atriplex spp., including Common Orach (Atriplex patula), are larvae of a fly, Pegomya hyoscyami (Spinach Leafminer); larvae of Emmelina monodactyla (Morning Glory Plume Moth), Chrysoesthia drurella (Goosefoot Leafminer Moth), and Chrysoesthia lingulacella (Flamboyent Twirler Moth); adults of Chaetocnema concinna (Brassy Flea Beetle); and Hayhurstia atriplicis (Chenopodium Aphid). Because the foliage and seeds of herbaceous Atriplex spp. are similar to those of Chenopodium spp., they may have similar floral-faunal relationships in the eastern United States. In particular, granivorous songbirds (e.g., various sparrows) probably eat the seeds.
Photographic Location: The photographs were taken near a vegetable garden in Urbana, Illinois, and along the edge of a wooded area in Champaign County, Illinois.
Comments: This plant has unusual arrowhead-shaped fruits. While other Atriplex spp. have such fruits, there are usually more lobes and other irregularities along the margins of their fruits. The foliage of Common Orach is very similar to the foliage of some Chenopodium spp. (Goosefoots). However, the latter have button-shaped fruits with 5 folded sepals. Because of the variability of its leaves, different varieties of Common Orach have been described. The typical variety (described here) has lanceolate leaves, while var. littoralis has linear leaves and var. hastata has triangular-hastate leaves. Some authorities consider these varieties to be different species (see Mohlenbrock, 2001). Common Orach should not be confused with Atriplex hortensis (Garden Orach), which is occasionally grown in gardens as either a potherb or ornamental plant. This latter species has fruits with nearly orbicular bracts that are conspicuously veined. In dry areas of the Western states, there are woody to semi-woody Atriplex spp. that are quite distinct. These are referred to as 'Saltbushes.'
The upper stems terminate in spikes or spike-like panicles of flowers; axillary spikes also develop from some of the upper leaves. The flowers are arranged in sessile clusters along the spikes or the branches of the panicles. Common Orach is monoecious with separate male (staminate) and female (pistillate) flowers on the same plant. Each male flower has 5 sepals and 5 stamens; it is whitish green and about 1/8" (3 mm.) across. Each female flower has an ovary with 2 styles and a pair of small bracts at its base; it is green and about 1/8" (3 mm.) across. The male flowers lack petals, while the female flowers have neither petals nor sepals. The flowers and branches of each inflorescence are white-mealy. The blooming period occurs during late summer into the fall. Pollination is by wind. The bracts of the female flowers enlarge in size, becoming triangular-hastate in shape and about 1/5" (5 mm.) in length; they form a flattened fruit that encloses the developing seed. Mature seeds are flattened, circular, and shiny black; each seed is covered by a thin rough membrane that is difficult to remove. The root system consists of a branching taproot. This plant spreads by reseeding itself.
Cultivation: The preference is full sun to light shade, moist to mesic conditions, and a fertile loamy soil. Toleration of salty alkaline conditions is quite good, although in Illinois this species is usually found in ordinary garden soil.
Range & Habitat: The adventive Common Orach occurs occasionally in central and northern Illinois, while in the southern part of the state it is uncommon (see Distribution Map). This species is native to Eurasia and northern Africa. Habitats include woodland borders, gardens, edges of yards, unmowed areas around telephone poles and tree stumps, areas along railroads and roadsides, dumps, and waste areas. Areas with a history of disturbance are preferred. In Illinois, this species is not invasive of natural habitats.
Faunal Associations: Insects that feed primarily on the leaves of Atriplex spp., including Common Orach (Atriplex patula), are larvae of a fly, Pegomya hyoscyami (Spinach Leafminer); larvae of Emmelina monodactyla (Morning Glory Plume Moth), Chrysoesthia drurella (Goosefoot Leafminer Moth), and Chrysoesthia lingulacella (Flamboyent Twirler Moth); adults of Chaetocnema concinna (Brassy Flea Beetle); and Hayhurstia atriplicis (Chenopodium Aphid). Because the foliage and seeds of herbaceous Atriplex spp. are similar to those of Chenopodium spp., they may have similar floral-faunal relationships in the eastern United States. In particular, granivorous songbirds (e.g., various sparrows) probably eat the seeds.
Photographic Location: The photographs were taken near a vegetable garden in Urbana, Illinois, and along the edge of a wooded area in Champaign County, Illinois.
Comments: This plant has unusual arrowhead-shaped fruits. While other Atriplex spp. have such fruits, there are usually more lobes and other irregularities along the margins of their fruits. The foliage of Common Orach is very similar to the foliage of some Chenopodium spp. (Goosefoots). However, the latter have button-shaped fruits with 5 folded sepals. Because of the variability of its leaves, different varieties of Common Orach have been described. The typical variety (described here) has lanceolate leaves, while var. littoralis has linear leaves and var. hastata has triangular-hastate leaves. Some authorities consider these varieties to be different species (see Mohlenbrock, 2001). Common Orach should not be confused with Atriplex hortensis (Garden Orach), which is occasionally grown in gardens as either a potherb or ornamental plant. This latter species has fruits with nearly orbicular bracts that are conspicuously veined. In dry areas of the Western states, there are woody to semi-woody Atriplex spp. that are quite distinct. These are referred to as 'Saltbushes.'
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Miss Chen
2018年07月24日
Description: This herbaceous perennial plant is 2-4' tall, branching abundantly in the upper half where the flowerheads occur. The stems are largely hairless, angular, and furrowed, although the upper flowering stems are usually pubescent. The lower stems often become reddish or woody in appearance with maturity. The alternate leaves are up to 4" long and 3" across, becoming smaller in size and more narrow as they ascend the stems. The upper surface of these leaves is green and hairless, while their lower surface is white from fine pubescent hairs. The lower and middle leaves usually have 1-2 pairs of deep primary lobes that are often irregularly spaced; these primary lobes are often shallowly cleft by one or more secondary lobes, or they have may a few large teeth. At the base of these leaves, there are often 1 or 2 small eared lobes. The upper leaves have few lobes or none, eventually becoming linear on the flowering stems.
The inflorescence is a large panicle of leafy spikes with flowerheads. Each flowerhead is 1/8" (3 mm.) across or a little larger, consisting of numerous rayless florets. The florets in the center of the flowerhead are fertile and perfect, while the florets along the outer margin of the flowerhead are fertile and pistillate. The central florets are tubular with 5 recurved lobes, while the marginal florets have only 1 or 2 lobes. All of these florets have a divided style. At the base of the flowerhead are several floral bracts that are finely pubescent. Except for their abundance, these flowerheads are inconspicuous. At the bud stage they are whitish green, becoming dull yellowish green or purplish green with maturity. The blooming period occurs from late summer to early fall, and lasts about 1 month. Pollination is by wind. Each floret is replaced by an oblong achene that is without a tuft of hairs. These achenes are small and light enough to be blown about by the wind. The root system is quite rhizomatous, and often produces clonal colonies of plants.
Cultivation: Mugwort prefers full or partial sun and moist to slightly dry conditions. It adapts well to loam, clay-loam, or gravelly soil, and slightly acid to alkaline conditions. This plant can spread aggressively, forming dense colonies that exclude other plants.
Range & Habitat: Surprisingly, Mugwort is a rather uncommon plant in Illinois, occurring in only a few counties in the northern half of the state (see Distribution Map). It was introduced into the United States from Eurasia as an herbal plant. Habitats include areas along railroads, edges of woods, prairie restorations, herbal gardens, and miscellaneous waste places. This plant usually occurs in disturbed areas, but it has displayed a capacity to invade more natural sites, even when fire is used as a management tool. This plant may become more of a problem in the future.
Faunal Associations: The flowerheads attract few insects because they are wind-pollinated. While the shrubby Artemisia spp. (Sagebrushes) of the western states are valuable to various kinds of wildlife, birds and mammals appear to make little use of the herbaceous Artemisia spp. that occur in the Midwest and NE states. The slightly aromatic foliage of Mugwort is bitter-tasting and toxic, containing cinerole and thujone. This latter substance is a neurotoxin. While Mugwort has been used in herbal medicine in the past, it can cause a variety of neurological problems and adverse reactions.
Photographic Location: Along the edge of a prairie restoration at Meadowbrook Park in Urbana, Illinois.
Comments: Mugwort is one of the introduced Artemisia spp. and rather nondescript in appearance. While significantly lobed, its leaves are usually broader than other Artemisia spp. and more tolerant of shade. These leaves are bicolored: green and largely hairless on the upper surface, but finely pubescent and powdery white underneath, whereas other Artemisia spp. tend to be either hairy or glabrous on both sides and less bicolored. Some Artemisia spp. have hairy or pubescent stems, while the stems of Mugwort are largely hairless (except for the upper flowering stems). Mugwort is unusual in having recurved lobes on its central disk florets – other Artemisia spp. usually have erect or spreading lobes on their disk florets. Because these florets are quite small in size, this can be difficult to observe without magnification from a hand or eye lens.
The inflorescence is a large panicle of leafy spikes with flowerheads. Each flowerhead is 1/8" (3 mm.) across or a little larger, consisting of numerous rayless florets. The florets in the center of the flowerhead are fertile and perfect, while the florets along the outer margin of the flowerhead are fertile and pistillate. The central florets are tubular with 5 recurved lobes, while the marginal florets have only 1 or 2 lobes. All of these florets have a divided style. At the base of the flowerhead are several floral bracts that are finely pubescent. Except for their abundance, these flowerheads are inconspicuous. At the bud stage they are whitish green, becoming dull yellowish green or purplish green with maturity. The blooming period occurs from late summer to early fall, and lasts about 1 month. Pollination is by wind. Each floret is replaced by an oblong achene that is without a tuft of hairs. These achenes are small and light enough to be blown about by the wind. The root system is quite rhizomatous, and often produces clonal colonies of plants.
Cultivation: Mugwort prefers full or partial sun and moist to slightly dry conditions. It adapts well to loam, clay-loam, or gravelly soil, and slightly acid to alkaline conditions. This plant can spread aggressively, forming dense colonies that exclude other plants.
Range & Habitat: Surprisingly, Mugwort is a rather uncommon plant in Illinois, occurring in only a few counties in the northern half of the state (see Distribution Map). It was introduced into the United States from Eurasia as an herbal plant. Habitats include areas along railroads, edges of woods, prairie restorations, herbal gardens, and miscellaneous waste places. This plant usually occurs in disturbed areas, but it has displayed a capacity to invade more natural sites, even when fire is used as a management tool. This plant may become more of a problem in the future.
Faunal Associations: The flowerheads attract few insects because they are wind-pollinated. While the shrubby Artemisia spp. (Sagebrushes) of the western states are valuable to various kinds of wildlife, birds and mammals appear to make little use of the herbaceous Artemisia spp. that occur in the Midwest and NE states. The slightly aromatic foliage of Mugwort is bitter-tasting and toxic, containing cinerole and thujone. This latter substance is a neurotoxin. While Mugwort has been used in herbal medicine in the past, it can cause a variety of neurological problems and adverse reactions.
Photographic Location: Along the edge of a prairie restoration at Meadowbrook Park in Urbana, Illinois.
Comments: Mugwort is one of the introduced Artemisia spp. and rather nondescript in appearance. While significantly lobed, its leaves are usually broader than other Artemisia spp. and more tolerant of shade. These leaves are bicolored: green and largely hairless on the upper surface, but finely pubescent and powdery white underneath, whereas other Artemisia spp. tend to be either hairy or glabrous on both sides and less bicolored. Some Artemisia spp. have hairy or pubescent stems, while the stems of Mugwort are largely hairless (except for the upper flowering stems). Mugwort is unusual in having recurved lobes on its central disk florets – other Artemisia spp. usually have erect or spreading lobes on their disk florets. Because these florets are quite small in size, this can be difficult to observe without magnification from a hand or eye lens.
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Miss Chen
2018年07月24日
Description: This plant is a summer annual about 3-6' tall; it is more or less erect and branches regularly. The light green stems are angular-terete, ridged, and hairless; the secondary stems are ascending or spreading. The alternate leaves are up to 6" long and 4" across, becoming smaller as they ascend the stems. They are green and hairless. Each leaf is pinnately divided (double or triple) into slender lobes that are narrowly lanceolate or oblong-lanceolate; some of these lobes are cleft or toothed along their margins. The lower leaves have petioles, while the upper leaves are sessile.
The upper stems terminate in floral panicles up to 1½' long and half as much across. The panicles are abundantly branched, each branch consisting of a raceme of small drooping flowerheads. about 1-2 mm. across (1/8" or less). Each flowerhead is about 2 mm. across (1/8" or less); it has many tiny disk florets. At the base of each flowerhead, there are 6 oblong bracts that are dark green. The blooming period occurs from late summer into the fall. There is no floral scent, although the foliage has a sweet fruity fragrance. Pollination is by wind. Upon maturity, each floret is replaced by a single achene. These achenes are small enough to be carried aloft by the wind, even though they lack tufts of hair. The root system consists of a branching taproot. This plant reproduces by reseeding itself.
Cultivation: The preference is full or partial sun, moist to mesic conditions, and fertile loamy soil with high nitrogen content. This plant also adapts to gravelly and sandy soil.
Range & Habitat: Annual Wormwood is occasional throughout Illinois (see Distribution Map). It was introduced from Eurasia as a medicinal herb. Escaped plants usually don't persist in a given location. Habitats include woodland borders, low-lying areas along rivers and ponds, fields, vacant lots, edges of yards, fence rows, gardens, back alleys in older cities, and areas along railroads and roadsides. Disturbed habitats are preferred. Annual Wormwood is still cultivated occasionally in gardens.
Faunal Associations: The wind-pollinated florets attract few insects, while the seeds are too small to be of much value to birds. Mammalian herbivores usually avoid consumption of Artemisia spp. (Wormwoods) because of the bitter compounds and mild to moderate toxicity of their foliage.
Photographic Location: Along a fence row in Urbana, Illinois. The flowerheads in the upper photograph are still in the bud stage.
Comments: Another common name for this plant is 'Sweet Annie.' Annual Wormwood is a non-woody summer annual that has hairless foliage with a sweet fruity fragrance. Other Artemisia spp. (Wormwoods) are often herbaceous biennials or woody perennials with hairy foliage (at least on the underside of their leaves). Many of these species have foliage with a smoky fragrance that resembles the seasoning 'Sage.' Annual Wormwood differs from a similar species, Artemisia biennis (Biennial Wormwood), by its double or triple pinnate leaves and spreading floral panicles. The latter species has simple pinnate leaves and a more spike-like inflorescence. The foliage of Annual Wormwood contains a chemical that is useful in the treatment of malaria.
The upper stems terminate in floral panicles up to 1½' long and half as much across. The panicles are abundantly branched, each branch consisting of a raceme of small drooping flowerheads. about 1-2 mm. across (1/8" or less). Each flowerhead is about 2 mm. across (1/8" or less); it has many tiny disk florets. At the base of each flowerhead, there are 6 oblong bracts that are dark green. The blooming period occurs from late summer into the fall. There is no floral scent, although the foliage has a sweet fruity fragrance. Pollination is by wind. Upon maturity, each floret is replaced by a single achene. These achenes are small enough to be carried aloft by the wind, even though they lack tufts of hair. The root system consists of a branching taproot. This plant reproduces by reseeding itself.
Cultivation: The preference is full or partial sun, moist to mesic conditions, and fertile loamy soil with high nitrogen content. This plant also adapts to gravelly and sandy soil.
Range & Habitat: Annual Wormwood is occasional throughout Illinois (see Distribution Map). It was introduced from Eurasia as a medicinal herb. Escaped plants usually don't persist in a given location. Habitats include woodland borders, low-lying areas along rivers and ponds, fields, vacant lots, edges of yards, fence rows, gardens, back alleys in older cities, and areas along railroads and roadsides. Disturbed habitats are preferred. Annual Wormwood is still cultivated occasionally in gardens.
Faunal Associations: The wind-pollinated florets attract few insects, while the seeds are too small to be of much value to birds. Mammalian herbivores usually avoid consumption of Artemisia spp. (Wormwoods) because of the bitter compounds and mild to moderate toxicity of their foliage.
Photographic Location: Along a fence row in Urbana, Illinois. The flowerheads in the upper photograph are still in the bud stage.
Comments: Another common name for this plant is 'Sweet Annie.' Annual Wormwood is a non-woody summer annual that has hairless foliage with a sweet fruity fragrance. Other Artemisia spp. (Wormwoods) are often herbaceous biennials or woody perennials with hairy foliage (at least on the underside of their leaves). Many of these species have foliage with a smoky fragrance that resembles the seasoning 'Sage.' Annual Wormwood differs from a similar species, Artemisia biennis (Biennial Wormwood), by its double or triple pinnate leaves and spreading floral panicles. The latter species has simple pinnate leaves and a more spike-like inflorescence. The foliage of Annual Wormwood contains a chemical that is useful in the treatment of malaria.
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Miss Chen
2018年07月11日
Description: This herbaceous perennial plant forms both basal leaves and erect to ascending stems with alternate leaves; the latter are 2-4' tall, branching occasionally. The stems are grayish green to nearly white, densely canescent, and terete, becoming more glabrous and slightly woody with age. Both the basal and lower alternate leaves are 2–4½" long and ¾–1¾" across (excluding their petioles); they are bipinnatifid to tripinnatifid. These leaves are deeply divided into primary lobes, while their ultimate lobes are more shallow and cleft. The ultimate lobes are 2-4 mm. across and narrowly oblong to narrowly oblanceolate in shape, tapering abruptly into bluntly acute tips. The middle alternate leaves are less divided and slightly smaller in size, while the upper alternate leaves are simple or sparingly lobed and even smaller in size. Both the upper and lower sides of the leaves are grayish green and sparsely to moderately canescent. The basal and lower alternate leaves have long petioles, while the middle alternate leaves have shorter petioles, and the upper alternate leaves are sessile or nearly so. Like the leaves, the petioles are grayish green and canescent. The foliage of this plant has a sage-like aroma with slightly bitter overtones. The upper stems terminate in panicles of flowers. Along the primary rachises of these panicles, there are primary leafy bracts at the bases of the secondary rachises; these primary bracts are up to 1" long, linear-oblong in shape, grayish green to nearly white, and canescent.
Secondary leafy bracts also occur at the bases of the peduncles on the secondary rachises; these secondary bracts are similar to the primary leafy bracts, except they are smaller in size. Both the primary and secondary rachises of the panicles are grayish green to nearly white and moderately to densely canescent; they are flat or slightly concave along their upper sides and rounded along their lower sides. The nodding flowerheads are 3-5 mm. across and 2-3 mm. tall; they are subgloboid in shape. Each flowerhead has 20-40 perfect disk florets that are surrounded by 10-20 pistillate disk florets; both types of florets are fertile. The florets are seperated by abundant silky hairs that originate from the receptacle. The tiny corollas of these florets are tubular in shape and 5-lobed along their upper rims. Overall, the appearance of these florets is yellowish brown. Along the sides of each flowerhead, there are small appressed phyllaries (floral bracts) in several overlapping series; these floral bracts are whitish green, densely canescent, and oblong to ovate in shape. The flowerheads have short curved peduncles that are whitish green and densely canescent. The blooming period occurs from mid-summer to early autumn, lasting 2-3 weeks for a colony of plants. The florets are cross-pollinated by the wind. Afterwards, the florets are replaced by small achenes. Mature achenes are 0.5–1 mm. long, narrowly oblongoid-oblanceoloid in shape, and light brown; they lack tufts of hair. The root system consists of a taproot up to ½" across. This plant reproduces by reseeding itself.
Cultivation: The preference is full or partial sun, moist to dry-mesic conditions, and soil containing loam, clay-loam, or some gravel. The soil should be well-drained. The size of individual plants can be highly variable depending on their age, moisture conditions, and soil fertility. For a herbaceous wormwood species (Artemisia), Absinthe tends to be long-lived.
Range & Habitat: Naturalized populations of Absinthe can be found in NE Illinois and scattered counties elsewhere, where it is relatively rare (see Distribution Map). All of these naturalized plants have escaped from cultivation. Absinthe was introduced into North America from Europe as an ornamental and medicinal plant. It is still cultivated occasionally in herb gardens today. In North America, this plant is more common in the northern plains of the United States and south-central Canada, where it is regarded as a weed of pastures. Habitats include pastures, sunny fence rows, gravelly areas along railroads, old homestead sites, and waste areas. Habitats with a history of disturbance are strongly preferred. In Illinois, Absinthe has difficulty to competing with taller native plants in natural areas.
Faunal Associations: Several species of aphids are known to feed on Absinthe (Artemisia absinthium); many of these species originated from Europe. Examples include such species as Coloradoa absinthii, Coloradoa angelicae, Coloradoa artemisiae, Macrosiphoniella absinthii (Absinthe Aphid), and other Macrosiphoniella spp. (Blackman & Eastop, 2013; Robinson & Bradley, 1965). Other insects that feed on wormwood species (Artemisia spp.) include Aphis middletonii(Erigeron Root Aphid), larvae of the leaf-miner fly Calycomyza artemisiae (Wormseed Webworm), larvae of the Gelechiid moth, Scrobipalpula artemisiella (Wormseed Webworm), and larvae of the Tortricid moths Eucosma agricolana and Phaneta dorsiatomana (Hottes & Frison, 1931; Spencer & Steyskal, 1986; Marcovitch, 1916; Miller, 1987). Some grasshoppers feed on these plants as well, including Hesperotettix viridis (Meadow Purple-striped Grasshopper), Hypochloa alba (Cudweed Grasshopper), and Melanoplus angustipennis (Narrow-winged Sand Grasshopper); see Vickery & Kevan (1985). Because the foliage of Absinthe is aromatic and bitter, it is not preferred as a source of food by herbivorous mammals. However, cattle and other domesticated livestock will feed on the foliage of Absinthe if little else is available. The consumption of a large quantity of foliage is potentially harmful as it contains the neurotoxin, thujone.
Photographic Location: An herb garden at Meadowbrook Park in Urbana, Illinois.
Comments: Absinthe (Artemisia absinthium) has been used to flavor an alcoholic liquor by the same name. Excessive consumption of this liquor has the potential to cause toxic effects and its use in some countries has been banned. Absinthe is similar in appearance to several other wormseed species (Artemisia spp.); both native and non-native species are present in Illinois. A native species that occurs in sandy areas, Beach Wormwood (Artemisia campestris), can be distinguished by the longer length and narrowness of the lobes of its leaves, the sterile florets in the center of its flowerheads, and the lack of villous hairs on the receptacle of its flowerheads. The presence of the last characteristic (villous hairs on the receptacles of the flowerheads) distinguishes Absinthe from all other wormseed species in Illinois, except for Prairie Sagebrush (Artemisia frigida). Prairie Sagebrush has smaller leaves with more narrow lobes (1 mm. across or less) than Absinthe, while its flowerheads are slightly larger in size (5-6 mm. across and 3-5 mm. tall). It is primarily a western species that is rarely found in Illinois.
Secondary leafy bracts also occur at the bases of the peduncles on the secondary rachises; these secondary bracts are similar to the primary leafy bracts, except they are smaller in size. Both the primary and secondary rachises of the panicles are grayish green to nearly white and moderately to densely canescent; they are flat or slightly concave along their upper sides and rounded along their lower sides. The nodding flowerheads are 3-5 mm. across and 2-3 mm. tall; they are subgloboid in shape. Each flowerhead has 20-40 perfect disk florets that are surrounded by 10-20 pistillate disk florets; both types of florets are fertile. The florets are seperated by abundant silky hairs that originate from the receptacle. The tiny corollas of these florets are tubular in shape and 5-lobed along their upper rims. Overall, the appearance of these florets is yellowish brown. Along the sides of each flowerhead, there are small appressed phyllaries (floral bracts) in several overlapping series; these floral bracts are whitish green, densely canescent, and oblong to ovate in shape. The flowerheads have short curved peduncles that are whitish green and densely canescent. The blooming period occurs from mid-summer to early autumn, lasting 2-3 weeks for a colony of plants. The florets are cross-pollinated by the wind. Afterwards, the florets are replaced by small achenes. Mature achenes are 0.5–1 mm. long, narrowly oblongoid-oblanceoloid in shape, and light brown; they lack tufts of hair. The root system consists of a taproot up to ½" across. This plant reproduces by reseeding itself.
Cultivation: The preference is full or partial sun, moist to dry-mesic conditions, and soil containing loam, clay-loam, or some gravel. The soil should be well-drained. The size of individual plants can be highly variable depending on their age, moisture conditions, and soil fertility. For a herbaceous wormwood species (Artemisia), Absinthe tends to be long-lived.
Range & Habitat: Naturalized populations of Absinthe can be found in NE Illinois and scattered counties elsewhere, where it is relatively rare (see Distribution Map). All of these naturalized plants have escaped from cultivation. Absinthe was introduced into North America from Europe as an ornamental and medicinal plant. It is still cultivated occasionally in herb gardens today. In North America, this plant is more common in the northern plains of the United States and south-central Canada, where it is regarded as a weed of pastures. Habitats include pastures, sunny fence rows, gravelly areas along railroads, old homestead sites, and waste areas. Habitats with a history of disturbance are strongly preferred. In Illinois, Absinthe has difficulty to competing with taller native plants in natural areas.
Faunal Associations: Several species of aphids are known to feed on Absinthe (Artemisia absinthium); many of these species originated from Europe. Examples include such species as Coloradoa absinthii, Coloradoa angelicae, Coloradoa artemisiae, Macrosiphoniella absinthii (Absinthe Aphid), and other Macrosiphoniella spp. (Blackman & Eastop, 2013; Robinson & Bradley, 1965). Other insects that feed on wormwood species (Artemisia spp.) include Aphis middletonii(Erigeron Root Aphid), larvae of the leaf-miner fly Calycomyza artemisiae (Wormseed Webworm), larvae of the Gelechiid moth, Scrobipalpula artemisiella (Wormseed Webworm), and larvae of the Tortricid moths Eucosma agricolana and Phaneta dorsiatomana (Hottes & Frison, 1931; Spencer & Steyskal, 1986; Marcovitch, 1916; Miller, 1987). Some grasshoppers feed on these plants as well, including Hesperotettix viridis (Meadow Purple-striped Grasshopper), Hypochloa alba (Cudweed Grasshopper), and Melanoplus angustipennis (Narrow-winged Sand Grasshopper); see Vickery & Kevan (1985). Because the foliage of Absinthe is aromatic and bitter, it is not preferred as a source of food by herbivorous mammals. However, cattle and other domesticated livestock will feed on the foliage of Absinthe if little else is available. The consumption of a large quantity of foliage is potentially harmful as it contains the neurotoxin, thujone.
Photographic Location: An herb garden at Meadowbrook Park in Urbana, Illinois.
Comments: Absinthe (Artemisia absinthium) has been used to flavor an alcoholic liquor by the same name. Excessive consumption of this liquor has the potential to cause toxic effects and its use in some countries has been banned. Absinthe is similar in appearance to several other wormseed species (Artemisia spp.); both native and non-native species are present in Illinois. A native species that occurs in sandy areas, Beach Wormwood (Artemisia campestris), can be distinguished by the longer length and narrowness of the lobes of its leaves, the sterile florets in the center of its flowerheads, and the lack of villous hairs on the receptacle of its flowerheads. The presence of the last characteristic (villous hairs on the receptacles of the flowerheads) distinguishes Absinthe from all other wormseed species in Illinois, except for Prairie Sagebrush (Artemisia frigida). Prairie Sagebrush has smaller leaves with more narrow lobes (1 mm. across or less) than Absinthe, while its flowerheads are slightly larger in size (5-6 mm. across and 3-5 mm. tall). It is primarily a western species that is rarely found in Illinois.
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Miss Chen
2018年07月10日
Description: This herbaceous biennial plant is a low-growing rosette of basal leaves during the first year, but during the second year it becomes 3-6' tall. The second-year plant is little branched below, but produces short flowering side stems above. The stems are rather stout, round or slightly ridged in circumference, and light green to slightly reddish green. Young stems are covered with white cobwebby hairs, but older stems become glabrous and have conspicuous longitudinal veins. The basal leaves are up to 2' long and 1½' across. They have long petioles and resemble the leaves of rhubarb to some extent. The lower leaves of second year plants resemble the basal leaves, except that they are somewhat smaller. These leaves are ovate-cordate, dull green above, and whitish green below, with blunt tips. They are nearly glabrous above, but finely pubescent below. Their margins are somewhat undulate, crisped, or smooth, sometimes with a few blunt teeth. Their long petioles have a conspicuous furrow above and they are usually hollow inside. The middle to upper leaves of second year plants are similar in appearance, but they are smaller in size and more likely to be ovate with margins that are more smooth and petioles that are shorter.
The upper stems terminate in small clusters of flowerheads on short stalks. Each flowerhead is about ¾–1" across, consisting of numerous disk florets and floral bracts that have narrow hooked tips. There are no ray florets. Each disk floret has a corolla that is narrowly cylindrical with 5 slender upright lobes at the apex. The disk florets are usually some shade of pink or purple, although a rare form of Common Burdock with white florets occurs. The slender white style is strongly exerted from the corolla and bifurcated at its tip. The dark purple anthers form a sheath around the style that lies just above the lobes of the corolla. The abundant bracts are green at the base, but become yellowish green toward the their hooked tips. They have a spiny appearance and have few, if any, cobwebby hairs in their midst. The blooming period occurs from mid-summer to early fall, and lasts about a month for a colony of plants. The achenes are oblong, broader and more truncate at one end than the other, and light brown with dark brown speckles. At the apex, each achene has a crown of fine bristles, but these are deciduous and soon fall off. The floral bracts turn brown and enclose the withered flowers at the top, forming a bur. The burs are persistent and remain on the stalks after the leaves have withered away during the fall. The root system consists of a stout taproot that runs deep into the ground. This plant spreads by reseeding itself, and often forms colonies of variable size.
Cultivation: Common Burdock is often found in full or partial sun, slightly moist to mesic conditions, and a loamy fertile soil. It has a robust nature and can be found in other kinds of soil and drier conditions. It is often aggressive.
Range & Habitat: This non-native plant is common in central and northern Illinois, but less common or absent in southern Illinois (see Distribution Map). This is by far the most common Arctium sp. (Burdock) in the state. It is adventive from Northern Europe and also occurs in Asia. Habitats include woodland edges, savannas, thickets, pastures, edges of fields and fence rows, weedy meadows, barnyards, areas along roads and railroads, and waste areas. Disturbed areas are preferred, although it occasionally appears in more pristine natural areas, particularly along paths and animal trails.
Faunal Associations: The flowers are pollinated primarily by long-tongued bees, including bumblebees, honeybees, Miner bees, and Leaf-Cutting bees, which suck nectar and collect pollen. Other visitors include bee flies, butterflies, and skippers, which seek nectar and are also effective at pollination. The caterpillars of several Papaipema spp. (Borer Moths) bore through the pith of the stems, including Papaipema cataphracta (Burdock Borer Moth), Papaipema arctivorens (Northern Burdock Borer Moth), and Papaipema rigida (Rigid Sunflower Borer Moth). The foliage of Common Burdock is one of the food sources for the caterpillars of the butterfly Vanessa cardui (Painted Lady). The Ring-Necked Pheasant eats the seeds to a limited extent. Because the foliage is bitter-tasting, Common Burdock is not a preferred food plant for mammalian herbivores, although livestock and deer will browse on it if nothing else is available. There is some evidence that the foliage may be toxic to rabbits. The seeds are distributed far and wide by animals and humans because the burs cling readily to fur and clothing. They are quite difficult to remove.
Photographic Location: Along a fence row at the webmaster's apartment complex in Urbana, Illinois.
Comments: Apparently, the stout taproot has a sweet taste and can be used as food. Similarly, if the outer husk of the stems are peeled away, the pith can be used like a vegetable. There are 3 Arctium spp. (Burdocks) in Illinois. One of them, Arctium tomentosum (Woolly Burdock) has abundant cobwebby hairs that cover the floral bracts below their hooked tips. Another species, Arctium lappa (Great Burdock), is often taller than Common Burdock, and it has larger flowerheads about 1–1½" across. The flowerheads of Great Burdock have longer stalks and they are arranged in flat-headed cymes, whereas the flowerheads of Common Burdock are more vertically bunched together on short stalks, as revealed in the upper photograph. The petioles of the lower leaves in Great Burdock are less furrowed on the upper surface and they are solid inside, rather than hollow.
The upper stems terminate in small clusters of flowerheads on short stalks. Each flowerhead is about ¾–1" across, consisting of numerous disk florets and floral bracts that have narrow hooked tips. There are no ray florets. Each disk floret has a corolla that is narrowly cylindrical with 5 slender upright lobes at the apex. The disk florets are usually some shade of pink or purple, although a rare form of Common Burdock with white florets occurs. The slender white style is strongly exerted from the corolla and bifurcated at its tip. The dark purple anthers form a sheath around the style that lies just above the lobes of the corolla. The abundant bracts are green at the base, but become yellowish green toward the their hooked tips. They have a spiny appearance and have few, if any, cobwebby hairs in their midst. The blooming period occurs from mid-summer to early fall, and lasts about a month for a colony of plants. The achenes are oblong, broader and more truncate at one end than the other, and light brown with dark brown speckles. At the apex, each achene has a crown of fine bristles, but these are deciduous and soon fall off. The floral bracts turn brown and enclose the withered flowers at the top, forming a bur. The burs are persistent and remain on the stalks after the leaves have withered away during the fall. The root system consists of a stout taproot that runs deep into the ground. This plant spreads by reseeding itself, and often forms colonies of variable size.
Cultivation: Common Burdock is often found in full or partial sun, slightly moist to mesic conditions, and a loamy fertile soil. It has a robust nature and can be found in other kinds of soil and drier conditions. It is often aggressive.
Range & Habitat: This non-native plant is common in central and northern Illinois, but less common or absent in southern Illinois (see Distribution Map). This is by far the most common Arctium sp. (Burdock) in the state. It is adventive from Northern Europe and also occurs in Asia. Habitats include woodland edges, savannas, thickets, pastures, edges of fields and fence rows, weedy meadows, barnyards, areas along roads and railroads, and waste areas. Disturbed areas are preferred, although it occasionally appears in more pristine natural areas, particularly along paths and animal trails.
Faunal Associations: The flowers are pollinated primarily by long-tongued bees, including bumblebees, honeybees, Miner bees, and Leaf-Cutting bees, which suck nectar and collect pollen. Other visitors include bee flies, butterflies, and skippers, which seek nectar and are also effective at pollination. The caterpillars of several Papaipema spp. (Borer Moths) bore through the pith of the stems, including Papaipema cataphracta (Burdock Borer Moth), Papaipema arctivorens (Northern Burdock Borer Moth), and Papaipema rigida (Rigid Sunflower Borer Moth). The foliage of Common Burdock is one of the food sources for the caterpillars of the butterfly Vanessa cardui (Painted Lady). The Ring-Necked Pheasant eats the seeds to a limited extent. Because the foliage is bitter-tasting, Common Burdock is not a preferred food plant for mammalian herbivores, although livestock and deer will browse on it if nothing else is available. There is some evidence that the foliage may be toxic to rabbits. The seeds are distributed far and wide by animals and humans because the burs cling readily to fur and clothing. They are quite difficult to remove.
Photographic Location: Along a fence row at the webmaster's apartment complex in Urbana, Illinois.
Comments: Apparently, the stout taproot has a sweet taste and can be used as food. Similarly, if the outer husk of the stems are peeled away, the pith can be used like a vegetable. There are 3 Arctium spp. (Burdocks) in Illinois. One of them, Arctium tomentosum (Woolly Burdock) has abundant cobwebby hairs that cover the floral bracts below their hooked tips. Another species, Arctium lappa (Great Burdock), is often taller than Common Burdock, and it has larger flowerheads about 1–1½" across. The flowerheads of Great Burdock have longer stalks and they are arranged in flat-headed cymes, whereas the flowerheads of Common Burdock are more vertically bunched together on short stalks, as revealed in the upper photograph. The petioles of the lower leaves in Great Burdock are less furrowed on the upper surface and they are solid inside, rather than hollow.
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