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Miss Chen
2018年07月31日
Miss Chen
Description: This plant is a spring or summer annual that becomes 3-10" tall, branching occasionally. The narrow round stems are covered with white hairs. The lower leaves are opposite, while the middle to upper leaves are alternate. These leaves are up to 1" long and 1/6" (4 mm.) across. They are linear-oblong or linear-oblanceolate, with margins that are ciliate and smooth. From the axil of each middle or upper leaf, a single flower develops from a slender pedicel about 1" long. Sometimes a second flower develops from the leaf axil. Like the stems, these pedicels are covered with white hairs. The flowers are up to 1/4" in length. The corolla is tubular, with 5 spreading lobes in the front and a short spur in the back. The corolla has a small opening at the throat and is more or less two-lipped with 2 upper lobes and 3 lower lobes. It is variously colored, usually some shade of lavender, light purple, or white. Sometimes the corolla is bicolored, with the upper lobes lavender or light purple and the lower lobes white. There are usually a few hairs at the base of the lower lobes. The calyx is green or purplish green and quite hairy. It has 5 oblanceolate lobes that are almost as long as the corolla. The blooming period occurs during the summer and it lasts about a month for a colony of plants. There is no noticeable floral scent. Each flower is replaced by an ovoid capsule that contains numerous brown seeds. These seeds are tiny enough to be dispersed by gusts of wind. The root system consists of a slender taproot. This plant spreads by reseeding itself. Cultivation: This little plant prefers dry sunny conditions and a sterile soil that is sandy or gravelly. It also grows in partial sun and less dry conditions, in which case it will become somewhat taller and more leafy. In fertile soil, this plant is not competitive with taller vegetation. Alkaline soil is readily tolerated.
Range & Habitat: The non-native Dwarf Snapdragon has been reported from most counties in Illinois (see Distribution Map). It is occasional to locally common. Habitats include gravelly areas along railroads (including the ballast), sandy or gravelly areas along roads, gravelly borders along buildings, and sterile waste areas. Disturbed areas are preferred. Dwarf Snapdragon is especially common along railroads in part because the wind gusts produced by passing trains help to disperse the tiny seeds. This plant is adventive from the Mediterranean area of Europe. It is less common along railroad tracks than formerly because of the application of herbicides. Faunal Association: Little information is available about floral-faunal relationships. The flowers are pollinated by small bees, although they are also capable of self-pollination. The seeds are too small to be of any interest to birds, and the insubstantial foliage is unlikely to provide much nourishment to mammalian herbivores. Humans assist in the dispersal of the seeds of this plant because of their passing trains and motor vehicles, as noted above.
Photographic Location: A border along a building that was filled with pebbles. This building was located along a railroad in Urbana, Illinois. Comments: Sometimes this plant is called "Small Snapdragon" and "Lesser Toadflax." It resembles the Linaria spp. (Toadflaxes) somewhat, except the throat of its corolla is less obstructed by fuzzy hairs and a palate covers the lower lip. Dwarf Snapdragon is one of the members of a group of plants that colonize disturbed sterile soil; these species are ecologically significant because they help to stabilize and restore the fertility of the soil. An alternative spelling of the scientific name for this plant is Chaenorrhinum minus.
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Miss Chen
2018年07月31日
Miss Chen
Description: This little plant is a winter or spring annual about 2-6" tall. A mature plant becomes tufted at the base, sending up multiple stems. These stems are green and pubescent. The opposite leaves are up to ¾" long and about half as much across. These leaves are broadly oblong or ovate-oblong, green, and pubescent; they have conspicuous central veins, smooth margins, and sessile bases. The upper stems terminate in small cymes or individual flowers; sometimes the lower cymes branch into secondary cymes of flowers. The peduncles and pedicels of these cymes are light green and pubescent. At the base of each peduncle, there is a pair of green leaf-like bracts. These bracts are broadly lanceolate-oblong or lanceolate-ovate, pubescent, and smooth along the margins; some of the upper bracts have thin translucent margins toward their tips (i.e., they are slightly scarious). These translucent margins are more apparent in mature or dried-out plants than young specimens. The flowers at the tips of the pedicels are up to ¼" across when they are fully open. Each flower has 5 white petals, 5 green sepals, 5 white styles, and 5 stamens with pale yellow anthers. Each petal has several pale lines at its base, while its tip is notched. The sepals are lanceolate and hairy; their margins are translucent. The blooming period occurs during the spring and lasts about 1 month; this is one of the earliest wildflowers to bloom during the spring. The flowers open up during spring days that are sunny and warm. Some plants begin to bloom when they are only 1" tall. Each flower is replaced by a cylindrical capsule containing manyDistribution Map small seeds. Each seed capsule is straight to slightly curved; there are 10 small teeth along its upper rim. The seeds are brown, somewhat flattened, and minutely warty or pebbly. The root system consists mostly of thin fibrous roots. This plant spreads by reseeding itself and it often forms small colonies. Cultivation: The preference is full sun, moist to slightly dry conditions, and sterile soil with little ground vegetation. In Illinois, this little plant completes its growth cycle during the spring. Range & Habitat: Small Mouse-Eared Chickweed is occasional in central and NE Illinois, while in other areas of the state it is uncommon or absent. This plant was accidentally introduced into the United States from Europe. Habitats consist of fields, disturbed grassy meadows, areas along roads, barren ground in lawns, and waste areas. Areas with a history of disturbance and environmental degradation are strongly preferred. This little plant tolerates road salt and other run-off chemicals better than most kinds of turf-grass; it also tolerates hardpan clay and gravel better than turf-grass. Faunal Associations: Like other Chickweeds (Cerastium spp., Stellaria spp.), the flowers of this species attract small bees and Syrphid flies. While the foliage of Small Mouse-Eared Chickweed is potentially edible to rabbits, it is rarely eaten because of its diminutive size and early spring growth. Small granivorous songbirds (e.g., sparrows) may use the seeds as a minor source of food. Photographic Location: A barren area along a roadside in Urbana, Illinois. Comments: There are several Cerastium spp. (Mouse-Eared Chickweeds) in Illinois and they are difficult to distinguish from each other. I believe that the species in the photograph above is Cerastium pumilum (Small Mouse-Eared Chickweed) for the following reasons: 1) It is a short-lived annual that completes its life-cycle during the spring, 2) Each of its flowers has 5 stamens and 5 styles, 3) Its flowers always have 5 petals, and 4) Its floral bracts usually lack translucent margins, except for some of the upper bracts on mature plants. Other Mouse-Eared Chickweeds are perennials (e.g., Cerastium fontanum), or they have flowers with 10 stamens (e.g., Cerastium brachypetalum, Cerastium glomeratum), or they produce flowers with 4 petals (e.g., Cerastium diffusum), or all of their bracts have conspicuous translucent margins (e.g., Cerastium semidecandrum).
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Miss Chen
2018年07月31日
Miss Chen
Description: This plant is a winter or spring annual that becomes 4-16" tall, usually forming a tuft of leafy stems that are ascending to sprawling. These stems are branched at the base near the crown of the plant, otherwise they are unbranched. Individual stems are light green, terete, and glandular-hairy. Pairs of opposite leaves occur along these stems (typically at intervals of 1-2½"). These leaves are ¾-2" long, 5-9 mm. across, and elliptic, oblong-lanceolate, or oblong-oblanceolate in shape. The leaf margins are smooth (entire) and slightly ciliate. The leaf surfaces are medium green and either sparsely short-pubescent or hairless. Each leaf has a prominent central vein. The upper stems terminate in either cymes or compound cymes of flowers (usually the latter); these cymes are dichotomously branched and variable in size. Each terminal branch of the inflorescence typically has 3 flowers with divergent slender pedicels up to 1¼" long. While the flower buds are nodding, the flowers are more erect. Similar to the stems, the branches and pedicels of each inflorescence are light green, terete, and glandular-pubescent. At the base of each pair of branches in an inflorescence, there is a pair of leafy bracts up to ¾" and 5 mm. across. These bracts are lanceolate in shape and they lack membranous margins. The flowers are up to ¼" across while they are in bloom. Each flower has 5 white petals with notched tips, 5 green sepals, an ovary with 5 styles, and 10 stamens (usually). The sepals are lanceolate in shape with membranous margins and short-pubescent; they are about 3-5 mm. long. The petals are the same length or a little longer than the sepals. The blooming period occurs from mid-spring to early summer, lasting about 1 month. Usually, only a few flowers are in bloom at the same time. Sometimes cleistogamous flowers that fail to open are produced.Distribution Map Afterwards, the flowers are replaced by cylindrical seed capsules that become 8-12 mm. long at maturity. Like the flowerbuds, they tend to nod downward. Mature seed capsules are membranous, light tan, longitudinally veined, and often slightly curved; they are more than twice as long as the sepals. Each seed capsule has an open rim at its apex with 10 tiny teeth. Each seed capsule contains several tiny seeds about 0.5 mm. in length. The seeds are obovoid, somewhat flattened, brownish, and minutely tuberculate (warty). The root system system consists of a shallow spreading taproot. Cultivation: The preference is full sun to light shade and moist conditions. Nodding Chickweed is not particular about soil. Most growth and development occurs during the spring when the weather is cool and moist, after which the foliage dies down. Range & Habitat: The native Nodding Chickweed is occasional to locally common in most areas of Illinois. Habitats include floodplain woodlands, streambanks in wooded areas, ravines and ledges along streams, gravel bars along rivers, weedy meadows, nursery plots, and moist waste areas. Nodding Chickweed occurs in both natural areas and human-mediated environments. In natural areas, it tends to occur in places where there is some disturbance by the action of water (e.g., soil erosion or deposits of gravel). Faunal Associations: The flowers are cross-pollinated by honeybees, Halictid bees (Halictus spp., Lasioglossum spp.), small butterflies, Syrphid flies, and other flies (Robertson, 1929). Both nectar and pollen are available as floral rewards. The caterpillars and cutworms of various moths are known to feed on chickweeds (Stellaria spp., Cerastium spp.). These moth species include Haematopis grataria (Chickweed Geometer), Lobocleta ossularia (Drab Brown Wave), Agrotis venerabilis (Venerable Dart), Hyles lineata (White-Lined Sphinx), Feltia jaculifera (Dingy Cutworm), Xestia badinodis (Spot-Sided Cutworm), and Xanthorhoe ferrugata (Red Twin-Spot). Vertebrate animals also feed on these plants to some extent. Various sparrows and other granivorous songbirds eat the seeds, while deer, rabbits, and domesticated farm animals (cattle, horses, sheep, & pigs) occasionally browse on the foliage. Photographic Location: A gravel bar along a river in a wooded area of Pine Hills State Nature Preserve in west-central Indiana.
Comments: Notwithstanding its weedy appearance and habits, this is one of the native chickweeds in Illinois. It is a rather floppy plant with small white flowers. Nodding Chickweed can be distinguished from other chickweeds (Stellaria spp., Cerastium spp.) by the shape of its leaves, diffuse inflorescence, and structure of its flowers. In particular, the pedicels of its flowers are rather long (1" in length or more) and divergent, while its flowerbuds and seed capsules nod downward. Among the Mouse-Eared Chickweeds (Cerastium spp.), Nodding Chickweed has rather long and narrow leaves. Some authorities consider the more western Cerastium brachypodum to be a variety of Nodding Chickweed, or Cerastium nutans obtectum. This latter species (or variety) tends to have more hairy leaves and its pedicels are shorter (less than 1" in length).
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Miss Chen
2018年07月31日
Miss Chen
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."
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Miss Chen
2018年07月30日
Miss Chen
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.
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Miss Chen
2018年07月30日
Miss Chen
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.
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Miss Chen
2018年07月30日
Miss Chen
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.
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Miss Chen
2018年07月30日
Miss Chen
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.
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Miss Chen
2018年07月30日
Miss Chen
Description: This herbaceous plant is either a biennial or summer annual (usually the former). It consists initially of a rosette of basal leaves. These basal leaves are 4-12" long and 1¼-4" across; they are lanceolate-pinnatifid or elliptic-pinnatifid with occasional secondary lobes. The margins of these leaves have white to golden yellow spines; larger spines occur at the tips of the primary and secondary lobes, while smaller spines occur along their sides and sinuses. The upper surfaces of the basal leaves are medium green and glabrous, while their lower surfaces are light to medium green and mostly glabrous, except for some short pubescence along the midveins. The petioles of these basal leaves are short and broadly winged. Later, this plant bolts, becoming 1½-6' tall and either unbranched or branched. The lower stem (or stems) tends to be light green and nearly glabrous toward the bottom, becoming increasingly white-tomentose above (white hairs that are appressed and woolly). In addition, the stems are terete and relatively stout; they lack spines, except where extensions of the leaf margins are decurrent. Alternate leaves occur along these stems, becoming gradually smaller as they ascend; they are 2-6" long and ½-1½" across. Alternate leaves are narrowly pinnatifid-lanceolate or narrowly pinnatifid-elliptic in shape. Compared to the lobes of basal leaves, the lobes of alternate leaves are more shallow, although the tips of these latter lobes are still spined. Alternate leaves are sessile; their margins have decurrent extensions along the stems, where they are spiny. The upper stems terminate in individual flowerheads about 1-3" across on long erect peduncles (up to 2' long). These peduncles are terete, stout, and white-tomentose; they are largely naked, except for widely-spaced leafy bracts. The flowerheads often nod to one side. Each flowerhead has 100-1000 disk florets that are narrowly cylindrical below, while above they divide into linear lobes (5 lobes per floret). The corollas of these florets are pink to purplish pink (rarely white); the styles of these florets are strongly exerted. Around the base of each flowerhead, there are relatively large phyllaries in several series. These phyllaries are deltate-ovate in shape; outer phyllaries are ascending, widely spreading, or descending; sometimes they are also recurved. The tips of the phyllaries are stiff and spiny. Immature flowerheads have green phyllaries, but they later become purplish. The blooming period occurs from early summer into the fall, lasting 1-4 months. The flowerheads are fragrant. Afterwards, the florets are replaced by achenes (4-5 mm. in length) with large tufts of hair. These achenes are bullet-shaped, slightly flattened, and ribbed. The primary hairs that are above these achenes have minute lateral hairs (may require 10x magnification to see). The achenes are distributed primarily by the wind. The root system develops a fleshy taproot. Cultivation: The preference is full sun, mesic conditions, and calcareous soil that is derived from either limestone or sand. However, Nodding Thistle (Carduus nutans) will adapt to almost any soil that is not extremely acidic. The size of individual plants can vary considerably depending on soil fertility and moisture levels. This thistle can reseed itself aggressively and become invasive. The seeds can remain viable for 3 or more years. Range & Habitat: The non-native Nodding Thistle (Carduus nutans) is occasional in most areas of Illinois (see Distribution Map), and it is probably still spreading within the state. This thistle is native to Eurasia and northern Africa; it was accidentally introduced into North America during the 19th century, possibly from dumped ship ballast along the east coast. In Illinois and other parts of North America, habitats include savannas, pastures, fallow fields, roadsides, areas along railroads, waste areas, and gardens or yards that use transported soil containing the seeds of this thistle. Nodding Thistle is particularly common in areas with calcareous sand (e.g., near major lakes) and limestone-derived soil. Disturbed areas are strongly preferred.
Faunal Associations: The flowerheads are cross-pollinated primarily by bumblebees and other long-tongued bees, butterflies, and skippers. In the absence of cross-pollination, the florets of the flowerheads are self-fertile. Both nectar and pollen are available as floral rewards. Because Nodding Thistle (Carduus nutans) is regarded as invasive in some parts of North America, various insects have been introduced from abroad to function as biocontrol agents. These species include: Rhinocyllus conicus (Thistlehead Weevil), whose larvae feed on the flowerheads; Trichosirocalus horridus (Thistle Crown Weevil), whose larvae feed on the growing points of rosettes and young shoots; Cheilosa corydon (Thistle Crown Fly), whose larvae burrow into shoots; Cassida rubiginosa (Thistle Tortoise Beetle), whose larvae and adults feed on leaves; and Psylliodes chalcomerus (Musk Thistle Leaf Beetle), whose larvae bore through stems, while the adults feed on leaves. Other insect feeders include Platyptilia carduidactylus (Artichoke Plume Moth) and Brachycaudus cardui (Thistle Aphid). The seeds of this thistle are eaten by a songbird, the Eastern Goldfinch, and the tufted hairs of its seeds are used in the construction of this bird's nests. Because of the spiny foliage, Nodding Thistle is rarely eaten by mammalian herbivores. However, sometimes cattle, sheep, and goats will eat the flowerheads or seedheads. It is unclear to what extent the seeds can survive passage in the digestive tracts of these animals, and thus their role in seed dispersal is still unclear.
Photographic Location: The photographed plant was cultivated in the webmaster's wildflower garden in Urbana, Illinois. However, this plant was found originally in the yard of the webmaster's apartment complex, where it had been transported in contaminated soil that was purchased from a local garden center. Comments: Nodding Thistle (Carduus nutans) has very showy and fragrant flowerheads, while its foliage is quite spiny. Until the nodding flowerheads are produced, it can be difficult to distinguish from other thistles. Like the Eurasian Bull Thistle (Cirsium vulgare), Nodding Thistle can be distinguished from native thistles by the spines on its stems (as derived from the decurrent margins of its leaves). It can be distinguished from the Bull Thistle by differences in the shape, size, and color of their respective phyllaries (floral bracts). The phyllaries of Nodding Thistle are larger in size, more broad at their bases, and become purple-colored when the flowerheads bloom; the phyllaries of Bull Thistle remain green at this time. In addition, the flowerheads of Nodding Thistle are usually more broad than those of Bull Thistle. Thistle species in the Carduus genus differ from thistle species in the Cirsium genus by the structure of the tufted hairs above their seeds. The tufted hairs of Carduus spp. (Musk Thistles) have barbed hairs from minute lateral hairs, while the tufted hairs of Cirsium spp. (Thistles) are more plumose (feathery) from longer lateral hairs. This is why Carduus nutans is sometimes referred to as the 'Plumeless Thistle,' even though its seeds have tufts of hair.
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Miss Chen
2018年07月29日
Miss Chen
Iris blooms make every ounce of care worth the effort. They offer such a wide range of colors and shape of flower that planting irises can be quite the gardening adventure. Most irises are surprisingly low-maintenance during the growing season, but all irises that grow in climates with cold winters will benefit from some form of winter protection.
Preparing for Winter While irises are low-maintenance, they require some minor care before winter sets in, if they are expected to provide those same big blooms next year. End-of-season care is also good for the health of the plant, providing an opportunity to inspect the iris bed in search of disease, dying plants or plants that need to be divided. After flowering, trim flower stalks as close to the ground as possible. This will give the plant one less part to worry about as its stores energy for winter. It's important to cut back the foliage or remove it once it's faded to yellow or brown. Cut it back to 6 inches in the fall while it's still green or wait until it's yellow or brown. Mulch Mulch is one of the simplest, most effective ways to protect the iris root system during frigid winter temperatures. Newly planted irises and established iris beds both benefit from a thick layer of mulch to protect the roots. Select pine needles, straw, leaves, compost or even just additional soil from the garden to make a 4- to 6-inch layer of mulch around the base of the plant, recommends the University of Minnesota Extension. Remove some of the mulch from around the new plants in spring as soon as possible--such as when the snow begins to melt--and the rest of the mulch once the garden has dried out. Dividing Irises If established irises need to be divided, do so in midsummer, about four to six weeks after all blooms have faded. The plants need time to establish a root system before the winter, reports the North Carolina State University Extension. Those irises will probably put up new growth before winter sets in, but their root systems won't be strong enough to resist freeze/thaw cycles that may occur during the winter and early spring. Mulch newly divided irises in late fall.
Freeze/Thaw Cycles Freeze/thaw cycles can wreak havoc on bulbs and tubers that overwinter in the garden. During these cycles, the already frozen ground thaws briefly, then freezes again, causing bulbs and tubers--irises, included--to be literally thrown from their beds. Of course, they can't survive this type of exposure, so a thick layer of mulch will help protect them.
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