文章
Miss Chen
2018年02月25日
Description: This biennial plant consists of a low-growing rosette of basal leaves up to 7" across during the 1st year. These basal leaves are up to 3½" long and ¾" across; they are green to greyish green, oblanceolate, dentate, and often slightly pinnatifid with shallow lobes. Their upper surface is often hairy, although they tend to become less hairy with age. During the 2nd year, Tower Mustard bolts during the spring and produces one or more flowering stalks up to 3½' tall. These stalks are light green to dull white, unbranched, hairless, and glaucous. Sometimes there may be a few hairs near the base of the stalks. The alternate cauline leaves are up to 3" long and 1" across. They are greyish green, lanceolate, smooth along the margins, hairless, and glaucous. Some of the lower cauline leaves may be dentate and slightly pinnatifid. The base of each cauline leaf clasps the stalk with a pair of basal lobes, which may be rounded or pointed. During cool spring weather, the cauline leaves may turn purple when they are exposed to full sun. Each stalk terminates in an elongated raceme of flowers and upright siliques (slender cylindrical seedpods). This raceme can become as long as the rest of the plant (up to 1¾' in length) and it has a tower-like appearance. Each flower at the apex of the raceme is up to 1/6" (4 mm.) across, consisting of 4 white or cream petals, 4 light green or yellow sepals, a stout style, and several stamens. The pedicels of the flowers and siliques are about ¼–½" in length.
The blooming period occurs during late spring to mid-summer and lasts about 1½ months. Each flower is replaced by a slender cylindrical silique up to 2½" long. The siliques are held upright close to stalk of the raceme. Each silique contains 1 or 2 rows of slightly flattened ovoid seeds. These small seeds have narrowly winged margins and they are dispersed to some extent by the wind. The root system consists of a stout taproot. This plant spreads by reseeding itself.
Cultivation: The preference is full sun to light shade, mesic to dry conditions, and loam, clay-loam, or rocky soil. This plant also tolerates soil containing sand or hardpan clay. It is fairly easy to grow from seed.
Range & Habitat: The native Tower Mustard occurs occasionally in the northern half of Illinois, but it is uncommon in the southern half of the state (see Distribution Map). Habitats include various kinds of prairies (sand, gravel, black soil, or clay), rocky open woodlands, barren savannas, limestone glades, rocky bluffs, and abandoned fields. In Illinois, Tower Mustard has low fidelity to any particular habitat. It also occurs in Eurasia.
Faunal Associations: Mostly small bees and flower flies visit the flowers for nectar or pollen. Occasionally various species of White butterflies (Pieridae) visit the flowers for nectar. The caterpillars of two Pierid butterflies, Anthocharis midea (Falcate Orangetip) and Euchloe olympia (Olympia Marble), prefer Arabis spp. (Rock Cresses) as a food source, particularly those Rock Cresses that are typically found in sunny habitats. The caterpillars of another Pierid butterfly, Pieris napi (Mustard White), reportedly feed on Rock Cresses, although this butterfly species hasn't been observed in Illinois since the 19th century. Little information appears to be available about the desirability of Tower Mustard as a food source for mammalian herbivores. However, the foliage is not particularly bitter nor peppery.
Photographic Location: The webmaster's wildflower garden in Urbana, Illinois.
Comments: Among the various Rock Cresses (Arabis spp. and related genera), Tower Mustard is mostly likely to be found in black soil prairies, although it also occurs in other kinds of habitats. The tower-like inflorescence gives this plant an odd appearance that is rather striking, especially when it becomes 3-4' tall. Because Tower Mustard is not difficult to grow and seems rather robust, it is rather surprising that this species is not more common. There are several Rock Cresses in Illinois, which can be found in either sunny or shady habitats, depending on the species. Some species have erect siliques that are appressed against the stalk of the raceme, while other species have siliques that are spreading or drooping. Tower Mustard belongs to the first group. Its appearance is similar to a very rare species, Arabis drummondii (Drummond's Rock Cress). This latter species has flattened siliques containing 2 rows of seeds and the style of its flowers is more slender than the style of Tower Mustard. Another species, Arabis hirsuta (Hairy Rock Cress), has hairs along at least the lower half of its flowering stalks, and it has flattened siliques containing a single row of seeds. The siliques of Tower Mustard are terete (round in cross-section). A scientific synonym of this plant is Arabis glabra.
The blooming period occurs during late spring to mid-summer and lasts about 1½ months. Each flower is replaced by a slender cylindrical silique up to 2½" long. The siliques are held upright close to stalk of the raceme. Each silique contains 1 or 2 rows of slightly flattened ovoid seeds. These small seeds have narrowly winged margins and they are dispersed to some extent by the wind. The root system consists of a stout taproot. This plant spreads by reseeding itself.
Cultivation: The preference is full sun to light shade, mesic to dry conditions, and loam, clay-loam, or rocky soil. This plant also tolerates soil containing sand or hardpan clay. It is fairly easy to grow from seed.
Range & Habitat: The native Tower Mustard occurs occasionally in the northern half of Illinois, but it is uncommon in the southern half of the state (see Distribution Map). Habitats include various kinds of prairies (sand, gravel, black soil, or clay), rocky open woodlands, barren savannas, limestone glades, rocky bluffs, and abandoned fields. In Illinois, Tower Mustard has low fidelity to any particular habitat. It also occurs in Eurasia.
Faunal Associations: Mostly small bees and flower flies visit the flowers for nectar or pollen. Occasionally various species of White butterflies (Pieridae) visit the flowers for nectar. The caterpillars of two Pierid butterflies, Anthocharis midea (Falcate Orangetip) and Euchloe olympia (Olympia Marble), prefer Arabis spp. (Rock Cresses) as a food source, particularly those Rock Cresses that are typically found in sunny habitats. The caterpillars of another Pierid butterfly, Pieris napi (Mustard White), reportedly feed on Rock Cresses, although this butterfly species hasn't been observed in Illinois since the 19th century. Little information appears to be available about the desirability of Tower Mustard as a food source for mammalian herbivores. However, the foliage is not particularly bitter nor peppery.
Photographic Location: The webmaster's wildflower garden in Urbana, Illinois.
Comments: Among the various Rock Cresses (Arabis spp. and related genera), Tower Mustard is mostly likely to be found in black soil prairies, although it also occurs in other kinds of habitats. The tower-like inflorescence gives this plant an odd appearance that is rather striking, especially when it becomes 3-4' tall. Because Tower Mustard is not difficult to grow and seems rather robust, it is rather surprising that this species is not more common. There are several Rock Cresses in Illinois, which can be found in either sunny or shady habitats, depending on the species. Some species have erect siliques that are appressed against the stalk of the raceme, while other species have siliques that are spreading or drooping. Tower Mustard belongs to the first group. Its appearance is similar to a very rare species, Arabis drummondii (Drummond's Rock Cress). This latter species has flattened siliques containing 2 rows of seeds and the style of its flowers is more slender than the style of Tower Mustard. Another species, Arabis hirsuta (Hairy Rock Cress), has hairs along at least the lower half of its flowering stalks, and it has flattened siliques containing a single row of seeds. The siliques of Tower Mustard are terete (round in cross-section). A scientific synonym of this plant is Arabis glabra.
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文章
Miss Chen
2018年02月24日
Description: This is a perennial plant that branches sparingly, and it is up to 3½' tall. The alternate leaves are bipinnately or ternately compound, and tend to be aggregated toward the base of the plant. The basal leaves are up to 12" long and 6" across, while smaller leaves are sparsely distributed along the middle and upper portions of the stems. Sometimes there are minute stiff hairs at the base of the petioles where the compound leaves meet the stem. The leaflets have large blunt teeth, and often occur in pairs or triplets, with the terminal leaflets achieving the largest size. Each leaflet is up to 1" long and ½" across, lanceolate or ovate, and has wedge-shaped lower margins. The overall appearance of the leaves resembles Italian Parsley.
Flowering Plant in Prairie
Rounded compound umbels of light yellow flowers occur at the ends of the central stem and major side stems. Each umbel is about 3" across, and is composed of 12-20 umbellets. Each umbellet consists of a similar number of tiny flowers, each one with 5 petals. There is no noticeable floral scent. The blooming period occurs during the late spring or early summer, and lasts about a month. The root system consists of a central taproot.
Cultivation: The preference is full or partial sun and mesic conditions. The soil can contain significant amounts of loam, sand, or rocky material. Light shade is tolerated, but growth will be less robust and flowering less abundant. Hairy-Jointed Meadow Parsnip develops rapidly during the spring, and is usually taller than the surrounding plants when the blooming period begins. After flowering, the condition of the plant rapidly deteriorates.
Range & Habitat: This native plant occurs occasionally in scattered counties of Illinois. Its distribution is oddly bifurcated, consisting primarily of counties in east-central and west-central Illinois (see Distribution Map). Habitats include mesic black soil prairies, openings in forests and woodland borders, sandy savannas, rocky bluffs, and the borders of lakes. This plant occurs in prairies to a greater extent than has been realized in the past.
Faunal Associations: Many kinds of insects are attracted to the flowers, especially short-tongued bees, wasps, flies, and beetles. The caterpillars of the butterfly Papilio polyxenes asterias (Black Swallowtail) feed on the foliage and flowers. This plant is not known to be toxic, and is probably consumed occasionally by various mammalian herbivores, although information about this is limited.
Photographic Location: The photographs of the flowering plant and compound leaf were taken at Loda Cemetery Prairie in Iroquois County, Illinois. The photograph of the umbels and upper leaves was taken at a woodland in Vermilion County, Illinois.
Comments: This native member of the Carrot family should be grown more often in wildflower gardens. Sometimes it is called 'Hairy Meadow Parnsip,' but conspicuous hairs occur only at the base of the petioles of compound leaves, and these are not easy to see unless you know where to look. This plant resembles the weedy and aggressive Pastinaca sativa (Wild Parsnip), but the latter has flat compound umbels of yellow flowers, while Hairy-Jointed Meadow Parsnip has compound umbels of pale yellow flowers that are more rounded. There are also significant differences in the structure of the compound leaves between these two species.
Flowering Plant in Prairie
Rounded compound umbels of light yellow flowers occur at the ends of the central stem and major side stems. Each umbel is about 3" across, and is composed of 12-20 umbellets. Each umbellet consists of a similar number of tiny flowers, each one with 5 petals. There is no noticeable floral scent. The blooming period occurs during the late spring or early summer, and lasts about a month. The root system consists of a central taproot.
Cultivation: The preference is full or partial sun and mesic conditions. The soil can contain significant amounts of loam, sand, or rocky material. Light shade is tolerated, but growth will be less robust and flowering less abundant. Hairy-Jointed Meadow Parsnip develops rapidly during the spring, and is usually taller than the surrounding plants when the blooming period begins. After flowering, the condition of the plant rapidly deteriorates.
Range & Habitat: This native plant occurs occasionally in scattered counties of Illinois. Its distribution is oddly bifurcated, consisting primarily of counties in east-central and west-central Illinois (see Distribution Map). Habitats include mesic black soil prairies, openings in forests and woodland borders, sandy savannas, rocky bluffs, and the borders of lakes. This plant occurs in prairies to a greater extent than has been realized in the past.
Faunal Associations: Many kinds of insects are attracted to the flowers, especially short-tongued bees, wasps, flies, and beetles. The caterpillars of the butterfly Papilio polyxenes asterias (Black Swallowtail) feed on the foliage and flowers. This plant is not known to be toxic, and is probably consumed occasionally by various mammalian herbivores, although information about this is limited.
Photographic Location: The photographs of the flowering plant and compound leaf were taken at Loda Cemetery Prairie in Iroquois County, Illinois. The photograph of the umbels and upper leaves was taken at a woodland in Vermilion County, Illinois.
Comments: This native member of the Carrot family should be grown more often in wildflower gardens. Sometimes it is called 'Hairy Meadow Parnsip,' but conspicuous hairs occur only at the base of the petioles of compound leaves, and these are not easy to see unless you know where to look. This plant resembles the weedy and aggressive Pastinaca sativa (Wild Parsnip), but the latter has flat compound umbels of yellow flowers, while Hairy-Jointed Meadow Parsnip has compound umbels of pale yellow flowers that are more rounded. There are also significant differences in the structure of the compound leaves between these two species.
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文章
Miss Chen
2018年02月24日
Description: This perennial plant is 3-7' tall, branching occasionally. The central stem is rather stout, green or reddish purple, and glaucous or slightly pubescent. The alternate leaves are ternately compound: A primary compound leaf divides into 3 secondary compound leaves, while each secondary compound leaf has 3 leaflets. Each leaflet is about ¾–2" long and half as much across. It is rounded at the base, and either unlobed or with 2-3 lobes toward the outer edge (usually a large middle lobe and 2 smaller side lobes). The margin of each leaflet turns downward slightly. The light green or white lower surface has a waxy appearance that is covered with glandular hairs. These hairs will glisten when they are exposed to sunlight. The lower surface of a leaflet also has a reticulated network of conspicuous veins. The foliage, when crushed in the hand, will produce a skunk-like smell.
Female Plant with Immature Fruits
Occasionally, the upper stems will produce panicles of flowers that are up to 2' long and about half as much across. Individual plants are usually unisexual, producing either male or female flowers. A male flower has 4-5 light green sepals that spread outward, while conspicuous white stamens with yellow or brown anthers occupy the center. Each male flower is about 1/3" long. The male flowers usually droop downward from slender pedicels, and together have an airy appearance that is rather pleasant. The female flowers are shaped like small green burs and have numerous short pistils. They are less attractive than the male flowers. The blooming period is from late spring to early summer, and lasts about 3 weeks. There is no floral scent. Pollination is by wind. The flowers are replaced by small achenes that are ribbed and pointed at both ends. The root system has rhizomes, which enables vegetative colonies to form. This plant gradually dies down during the summer, but forms new vegetation at the base during the fall.
Cultivation: The preference is moist to slight dry conditions, and partial to full sun. This plant usually grows in fairly typical garden soil, such as a rich loam or clay loam. The height of a plant can vary considerably depending on fertility of the soil, moisture conditions, and maturity. Vegetative growth is very rapid during the spring. This species of Meadow Rue appears to tolerate full sun and droughty conditions better than most.
Range & Habitat: Waxy Meadow Rue is widely distributed in Illinois, where it is native. This plant occurs occasionally in central and northern Illinois, but it is less common or absent in southern Illinois (see Distribution Map). Habitats include mesic black soil prairies, thickets and woodland borders, savannas, and areas along railroads and roadsides, especially where remnant prairies occur.
Faunal Associations: Because the flowers are wind-pollinated, few insects visit the flowers. Occasionally bees gather pollen from the anthers of the male flowers, while various kinds of beetles eat the pollen. Because the foliage has a foul scent, it probably is not a preferred food source for mammalian herbivores.
Photographic Location: The photographs were taken at the Red Bison Railroad Prairie in Savoy, Illinois. The plants were growing in full sunlight under mesic conditions.
Comments: This plant is reasonably attractive while in bloom, but this doesn't last very long. The various Thalictrum spp. have very similar flowers, but can be distinguished by their foliage. Waxy Meadow Rue has glandular hairs on the undersides of the leaflets (which glisten in the sunlight), and the foliage has a foul scent when it is crushed. Another species, Thalictrum dasycarpum (Purple Meadow Rue), has a very similar appearance, but the hairs on the undersides of the leaflets (if present) are non-glandular, while the foliage has little scent. Either of these plants can occur in prairies. Another species that is fairly common in Illinois, Thalictrum dioicum (Early Meadow Rue), is a shorter plant that blooms earlier and occurs in woodlands. However, the terminal leaflets of this species have 5 lobes toward the outer margin, while the terminal leaflets of Waxy and Purple Meadow Rue have only 3 lobes.
Female Plant with Immature Fruits
Occasionally, the upper stems will produce panicles of flowers that are up to 2' long and about half as much across. Individual plants are usually unisexual, producing either male or female flowers. A male flower has 4-5 light green sepals that spread outward, while conspicuous white stamens with yellow or brown anthers occupy the center. Each male flower is about 1/3" long. The male flowers usually droop downward from slender pedicels, and together have an airy appearance that is rather pleasant. The female flowers are shaped like small green burs and have numerous short pistils. They are less attractive than the male flowers. The blooming period is from late spring to early summer, and lasts about 3 weeks. There is no floral scent. Pollination is by wind. The flowers are replaced by small achenes that are ribbed and pointed at both ends. The root system has rhizomes, which enables vegetative colonies to form. This plant gradually dies down during the summer, but forms new vegetation at the base during the fall.
Cultivation: The preference is moist to slight dry conditions, and partial to full sun. This plant usually grows in fairly typical garden soil, such as a rich loam or clay loam. The height of a plant can vary considerably depending on fertility of the soil, moisture conditions, and maturity. Vegetative growth is very rapid during the spring. This species of Meadow Rue appears to tolerate full sun and droughty conditions better than most.
Range & Habitat: Waxy Meadow Rue is widely distributed in Illinois, where it is native. This plant occurs occasionally in central and northern Illinois, but it is less common or absent in southern Illinois (see Distribution Map). Habitats include mesic black soil prairies, thickets and woodland borders, savannas, and areas along railroads and roadsides, especially where remnant prairies occur.
Faunal Associations: Because the flowers are wind-pollinated, few insects visit the flowers. Occasionally bees gather pollen from the anthers of the male flowers, while various kinds of beetles eat the pollen. Because the foliage has a foul scent, it probably is not a preferred food source for mammalian herbivores.
Photographic Location: The photographs were taken at the Red Bison Railroad Prairie in Savoy, Illinois. The plants were growing in full sunlight under mesic conditions.
Comments: This plant is reasonably attractive while in bloom, but this doesn't last very long. The various Thalictrum spp. have very similar flowers, but can be distinguished by their foliage. Waxy Meadow Rue has glandular hairs on the undersides of the leaflets (which glisten in the sunlight), and the foliage has a foul scent when it is crushed. Another species, Thalictrum dasycarpum (Purple Meadow Rue), has a very similar appearance, but the hairs on the undersides of the leaflets (if present) are non-glandular, while the foliage has little scent. Either of these plants can occur in prairies. Another species that is fairly common in Illinois, Thalictrum dioicum (Early Meadow Rue), is a shorter plant that blooms earlier and occurs in woodlands. However, the terminal leaflets of this species have 5 lobes toward the outer margin, while the terminal leaflets of Waxy and Purple Meadow Rue have only 3 lobes.
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Miss Chen
2018年02月24日
Description: This perennial wildflower consists of a rosette, or clustered rosettes, of basal leaves from which one or more flowering stalks develop. The ascending to spreading basal leaves are 1-6" long and 1/8–1/2" (3-12 mm.) across; they areColonies of Flowering Plants dark green, linear-oblanceolate in shape, smooth along their margins, and mostly hairless. The leaves of plants that are under stress from drought may become grayish green. Individual flowerheads develop at the apex of unbranched stalks that are 4-12" high; these flowering stalks are more or less erect. The stalks are rather stout and more or less finely pubescent. Individual flowerheads span 1-1¾" across, consisting of 10-30 ray florets that surround a dense cluster of 50 or more disk florets. The petal-like rays of the ray florets are ¼–¾" long, bright yellow, oblong in shape, and divided into 3 blunt teeth at their tips. The tiny disk florets are golden yellow, tubular in shape, and lobed along their upper rims. Both ray and disk florets are fertile. Around the base of each flowerhead, there are green floral bracts (phyllaries) in 2-3 series. Individual floral bracts are about ¼" in length, finely pubescent, and oblong-ovate with rounded tips. The blooming period usually occurs from late spring to early summer. A colony of plants may bloom for about a month. The florets are replaced by small achenes that are angular and finely pubescent; they become mature during the summer. At the apex of each achene, there is a tiny crown of 5 or more chaffy scales that are lanceolate in shape. The achenes are distributed by gravity and wind, although they usually don't travel far from the mother plant. The root system consists of a short stout caudex that eventually branches, forming a cluster of plants from vegetative offsets.
Cultivation: The preference is full sun, well-drained mesic to dry conditions, and a gritty alkaline soil containing gravel or rocky material. This wildflower can be cultivated in rock gardens. The seeds require no winter dormancy and should be sowed during the same year that they are produced.
Range & Habitat: Lakeside Daisy is a rare native wildflower in Illinois, having been found in only Tazewell and Will counties (see Distribution Map). It is state-listed as 'endangered' and federally listed as 'threatened.' At one time, this wildflower was extirpated from the wild in Illinois, although it still existed in private gardens in the Chicago area. More recently, it has been successfully reintroduced in various natural areas of the state. The largest population in the United States exists in Marblehead Peninsula along Lake Erie in Ohio. Habitats consist of dry dolomite prairies and gravel prairies, gravelly hill prairies, sand-gravel terraces along major rivers, ledges along cliffs, and limestone quarries. This wildflower is found in rocky areas with sparse vegetation and can tolerate minor amounts of disturbance.
Faunal Associations: Both nectar and pollen are available from the flowerheads, which attract bees, flies, beetles, butterflies, and skippers. Floral bee visitors include bumblebees, small carpenter bees (Ceratina spp.), and Halictid bees. Cross-pollination is required because individual plants are genetically self-incompatible. Insects that feed on the Lakeside Daisy include grasshoppers and the larvae of an unidentified weevil; the latter feeds on the seeds. The flowering stalks are eaten occasionally by the White-Tailed Deer and Cottontail Rabbit. In the Western states, related species in the Hymenoxys/Tetraneuris complex are known to have toxic leaves that can poison cattle and sheep, however the toxicity of the more eastern Lakeside Daisy has not been determined.
Photographic Location: A botanical garden in the Chicago area. The photographs of the Lakeside Daisy were taken by Jim Ault (Copyright © 2010).
Comments: The Lakeside Daisy is an attractive plant. This wildflower is rare because of its restrictive habitat requirements and the limited distribution of its seeds. Lakeside Daisy is one of several spring-blooming species in the Aster family that have yellow flowerheads and rosettes of basal leaves. It can be distinguished from these other species by its narrow dark green leaves, unbranched flowering stalks, three-toothed rays, and achenes with tiny crowns of scales (rather than a tufts of hairs). Other closely related species exist in the Western states. The Lakeside Daisy is sometimes classified as var. glabra of the western Hymenoxys acaulis. However, this latter species differs by having fewer ray florets (less than 15), floral bracts (phyllaries) with awned pointed tips, and basal leaves that are gray-green with silky hairs.
Cultivation: The preference is full sun, well-drained mesic to dry conditions, and a gritty alkaline soil containing gravel or rocky material. This wildflower can be cultivated in rock gardens. The seeds require no winter dormancy and should be sowed during the same year that they are produced.
Range & Habitat: Lakeside Daisy is a rare native wildflower in Illinois, having been found in only Tazewell and Will counties (see Distribution Map). It is state-listed as 'endangered' and federally listed as 'threatened.' At one time, this wildflower was extirpated from the wild in Illinois, although it still existed in private gardens in the Chicago area. More recently, it has been successfully reintroduced in various natural areas of the state. The largest population in the United States exists in Marblehead Peninsula along Lake Erie in Ohio. Habitats consist of dry dolomite prairies and gravel prairies, gravelly hill prairies, sand-gravel terraces along major rivers, ledges along cliffs, and limestone quarries. This wildflower is found in rocky areas with sparse vegetation and can tolerate minor amounts of disturbance.
Faunal Associations: Both nectar and pollen are available from the flowerheads, which attract bees, flies, beetles, butterflies, and skippers. Floral bee visitors include bumblebees, small carpenter bees (Ceratina spp.), and Halictid bees. Cross-pollination is required because individual plants are genetically self-incompatible. Insects that feed on the Lakeside Daisy include grasshoppers and the larvae of an unidentified weevil; the latter feeds on the seeds. The flowering stalks are eaten occasionally by the White-Tailed Deer and Cottontail Rabbit. In the Western states, related species in the Hymenoxys/Tetraneuris complex are known to have toxic leaves that can poison cattle and sheep, however the toxicity of the more eastern Lakeside Daisy has not been determined.
Photographic Location: A botanical garden in the Chicago area. The photographs of the Lakeside Daisy were taken by Jim Ault (Copyright © 2010).
Comments: The Lakeside Daisy is an attractive plant. This wildflower is rare because of its restrictive habitat requirements and the limited distribution of its seeds. Lakeside Daisy is one of several spring-blooming species in the Aster family that have yellow flowerheads and rosettes of basal leaves. It can be distinguished from these other species by its narrow dark green leaves, unbranched flowering stalks, three-toothed rays, and achenes with tiny crowns of scales (rather than a tufts of hairs). Other closely related species exist in the Western states. The Lakeside Daisy is sometimes classified as var. glabra of the western Hymenoxys acaulis. However, this latter species differs by having fewer ray florets (less than 15), floral bracts (phyllaries) with awned pointed tips, and basal leaves that are gray-green with silky hairs.
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Miss Chen
2018年02月23日
Description: This herbaceous perennial plant is 1½–3' tall and largely unbranched, except near the inflorescence. The central stem is light green, terete, and glabrous to sparsely short-hairy. Alternate leaves occur along the central stem, becoming shorter and more narrow as they ascend. The lower leaves are up to 3" long and 1½" across; they are narrowly oval to ovate in shape and smooth along their margins. The middle leaves are up to 2½" long and ¾" across; they are narrowly lanceolate to lanceolate in shape and smooth along their margins. The upper leaves are up to 1¼" long and ¼" across; they are linear-oblong in shape and smooth along their margins. The upper leaf surfaces are medium to dark green and glabrous or nearly so, while their lower surfaces are light green and glabrous to short-hairy along the major veins. The petioles of these leaves are up to 2" long, becoming shorter as they ascend the stem – however the upper leaves are sessile. The petioles are light green, concave above and convex below, and glabrous to slightly hairy. In addition to the deciduous alternate leaves, this plant also produces a loose tuft of semi-evergreen basal leaves. These basal leaves are similar in appearance to the lower alternate leaves, except they are more broad (oval to oval-cordate in shape) and their margins are sometimes crenate-serrate. The petioles of basal leaves are up to 3" long. The central stem terminates in a panicle of flowerheads that is ½–1½' long and about one-half as much across. When a plant is in bloom, it often leans to one side because of the weight of the inflorescence.
Several Flowerheads
The panicle has a rachis (central stalk) and several ascending primary branches; these branches divide into secondary and tertiary branches that terminate in daisy-like flowerheads. The rachis and branches are light green and glabrous to sparsely short-hairy; scale-like to linear leafy bracts up to ¾" long occur at intervals along these branches. Each flowerhead is about ½" across or slightly larger, consisting of 10-25 ray florets that surround numerous disk florets. The petaloid rays are lavender or light blue (rarely white), linear-oblong in shape, slightly notched at their tips, and widely spreading. The tiny corollas of the disk florets are tubular in shape with 5 ascending to spreading lobes along their upper rims; these corollas are initially yellow, but they later become purplish red and finally brown. Surrounding the base of each flowerhead, there are scale-like bracts (phyllaries) that are arranged in 3-5 series that are appressed together or slightly spreading. These floral bracts are about 2 mm. long, lanceolate in shape, and mostly light green, except toward their tips, where there are dark green patches that are diamond-shaped. The blooming period occurs from late summer into autumn, lasting about 1 month for a colony of plants. Afterwards, the florets are replaced by small bullet-shaped achenes (about 2 mm. in length) that have small tufts of hair at their apices. These achenes are distributed by the wind. The root system is fibrous and rhizomatous; older plants may develop a short caudex.
Cultivation: The preference is full or partial sun and mesic to dry conditions. This plant is rather indifferent to soil characteristics – it can flourish in soil that is loamy, sandy, rocky, or contains clay. This plant is easy to grow and drought resistant; the lower leaves are occasionally marred by powdery mildew and other foliar diseases.
Range & Habitat: The native Sky Blue Aster occurs occasionally in the northern and western halves of Illinois, but it is uncommon or absent elsewhere (see Distribution Map). Habitats include mesic to dry prairies, sand prairies, hill prairies, rocky upland woodlands, upland savannas, upland sandy savannas, woodland borders, sandy meadows, limestone glades, and roadside embankments. This plant is usually found in higher quality natural areas where the original ground flora is still intact. Occasional wildfires or other disturbance that reduce competition from woody vegetation is beneficial in maintaining populations of this plant.
Faunal Associations: For Sky Blue Aster, the nectar and pollen of the flowerheads attract bumblebees, digger bees (Melissodes spp.), leaf-cutting bees (Megachile spp.), Halictid bees (Agapostemon spp., Halictus spp., Lasioglossum spp.), Andrenid bees, Syrphid flies, bee flies (Bombyliidae), butterflies, skippers, miscellaneous beetles, and other insects (Reed, 1993). Bees that are specialist pollinators (oligoleges) of asters (Symphyotrichum spp.) and closely related composites include Andrena asteris, Andrena nubecula, Andrena simplex, Colletes simulans armatus, and Melissodes dentiventris. Other insects feed destructively on the leaves, flowerheads, and other parts of asters. These species include larvae of the Aster Leafminer Fly (Calycomyza humeralis), larvae of the Papery Blister Gall Midge (Asteromyia laeviana), larvae of fruit flies, plant bugs, the Goldenrod Lace Bug (Corythucha marmorata), aphids (especially Uroleucon spp.), the Aster Leafhopper (Macrosteles fascifrons), Blatchley's Walkingstick (Manomera blatchleyi), and grasshoppers (see the Insect Table for a listing of these and other species). In addition, larvae of the butterflies Silvery Checkerspot (Chlosyne nycteis) and Pearl Crescent (Phyciodes tharos) feed on asters, as do larvae of the Aster Borer Moth (Carmenta corni), The Asteroid (Cucullia asteroides), and many other moths (see Moth Table). Among birds, the Ruffed Grouse and Wild Turkey browse on the leaves and seeds of asters; the Tree Sparrow also eats the seeds during the winter. Among mammals, the Cottontail Rabbit and White-Tailed Deer browse on the foliage, while the White-footed Mouse eats the seeds (Martin et al., 1951/1961). Groundhogs, cattle, horses, and other livestock also browse on the foliage, especially when it is young and tender.
Photographic Location: The photographs were taken at the webmaster's wildflower garden in Urbana, Illinois.
Comments: For the size of the plant, the inflorescence of Sky Blue Aster (Symphyotrichum oolentangiense) is rather large and showy. This species of aster closely resembles Short's Aster (Symphyotrichum shortii), even though the latter species is a woodland aster. However, the upper leaves of Short's Aster are often narrowly cordate, rather than narrowly lanceolate or linear, and its flowerheads are slightly larger in size. Another similar species, Smooth Blue Aster (Symphyotrichum laeve), has alternate leaves that are all sessile, while Sky Blue Aster has lower to middle leaves with petioles. Other asters (Symphyotrichum spp.) have hairier foliage, or their leaves are narrow throughout, or they have more cordate leaves, or their alternate leaves have toothed margins. Older scientific names for Sky Blue Aster include Aster azureus and Aster oolentangiensis, while another common name for this species is Azure Aster.
Several Flowerheads
The panicle has a rachis (central stalk) and several ascending primary branches; these branches divide into secondary and tertiary branches that terminate in daisy-like flowerheads. The rachis and branches are light green and glabrous to sparsely short-hairy; scale-like to linear leafy bracts up to ¾" long occur at intervals along these branches. Each flowerhead is about ½" across or slightly larger, consisting of 10-25 ray florets that surround numerous disk florets. The petaloid rays are lavender or light blue (rarely white), linear-oblong in shape, slightly notched at their tips, and widely spreading. The tiny corollas of the disk florets are tubular in shape with 5 ascending to spreading lobes along their upper rims; these corollas are initially yellow, but they later become purplish red and finally brown. Surrounding the base of each flowerhead, there are scale-like bracts (phyllaries) that are arranged in 3-5 series that are appressed together or slightly spreading. These floral bracts are about 2 mm. long, lanceolate in shape, and mostly light green, except toward their tips, where there are dark green patches that are diamond-shaped. The blooming period occurs from late summer into autumn, lasting about 1 month for a colony of plants. Afterwards, the florets are replaced by small bullet-shaped achenes (about 2 mm. in length) that have small tufts of hair at their apices. These achenes are distributed by the wind. The root system is fibrous and rhizomatous; older plants may develop a short caudex.
Cultivation: The preference is full or partial sun and mesic to dry conditions. This plant is rather indifferent to soil characteristics – it can flourish in soil that is loamy, sandy, rocky, or contains clay. This plant is easy to grow and drought resistant; the lower leaves are occasionally marred by powdery mildew and other foliar diseases.
Range & Habitat: The native Sky Blue Aster occurs occasionally in the northern and western halves of Illinois, but it is uncommon or absent elsewhere (see Distribution Map). Habitats include mesic to dry prairies, sand prairies, hill prairies, rocky upland woodlands, upland savannas, upland sandy savannas, woodland borders, sandy meadows, limestone glades, and roadside embankments. This plant is usually found in higher quality natural areas where the original ground flora is still intact. Occasional wildfires or other disturbance that reduce competition from woody vegetation is beneficial in maintaining populations of this plant.
Faunal Associations: For Sky Blue Aster, the nectar and pollen of the flowerheads attract bumblebees, digger bees (Melissodes spp.), leaf-cutting bees (Megachile spp.), Halictid bees (Agapostemon spp., Halictus spp., Lasioglossum spp.), Andrenid bees, Syrphid flies, bee flies (Bombyliidae), butterflies, skippers, miscellaneous beetles, and other insects (Reed, 1993). Bees that are specialist pollinators (oligoleges) of asters (Symphyotrichum spp.) and closely related composites include Andrena asteris, Andrena nubecula, Andrena simplex, Colletes simulans armatus, and Melissodes dentiventris. Other insects feed destructively on the leaves, flowerheads, and other parts of asters. These species include larvae of the Aster Leafminer Fly (Calycomyza humeralis), larvae of the Papery Blister Gall Midge (Asteromyia laeviana), larvae of fruit flies, plant bugs, the Goldenrod Lace Bug (Corythucha marmorata), aphids (especially Uroleucon spp.), the Aster Leafhopper (Macrosteles fascifrons), Blatchley's Walkingstick (Manomera blatchleyi), and grasshoppers (see the Insect Table for a listing of these and other species). In addition, larvae of the butterflies Silvery Checkerspot (Chlosyne nycteis) and Pearl Crescent (Phyciodes tharos) feed on asters, as do larvae of the Aster Borer Moth (Carmenta corni), The Asteroid (Cucullia asteroides), and many other moths (see Moth Table). Among birds, the Ruffed Grouse and Wild Turkey browse on the leaves and seeds of asters; the Tree Sparrow also eats the seeds during the winter. Among mammals, the Cottontail Rabbit and White-Tailed Deer browse on the foliage, while the White-footed Mouse eats the seeds (Martin et al., 1951/1961). Groundhogs, cattle, horses, and other livestock also browse on the foliage, especially when it is young and tender.
Photographic Location: The photographs were taken at the webmaster's wildflower garden in Urbana, Illinois.
Comments: For the size of the plant, the inflorescence of Sky Blue Aster (Symphyotrichum oolentangiense) is rather large and showy. This species of aster closely resembles Short's Aster (Symphyotrichum shortii), even though the latter species is a woodland aster. However, the upper leaves of Short's Aster are often narrowly cordate, rather than narrowly lanceolate or linear, and its flowerheads are slightly larger in size. Another similar species, Smooth Blue Aster (Symphyotrichum laeve), has alternate leaves that are all sessile, while Sky Blue Aster has lower to middle leaves with petioles. Other asters (Symphyotrichum spp.) have hairier foliage, or their leaves are narrow throughout, or they have more cordate leaves, or their alternate leaves have toothed margins. Older scientific names for Sky Blue Aster include Aster azureus and Aster oolentangiensis, while another common name for this species is Azure Aster.
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Miss Chen
2018年02月23日
Description: This perennial herbaceous plant is 1–3½' tall, branching occasionally. The central stem and lateral stems are light green to dull red, terete, and sometimes shallowly grooved; they usually have vertical lines of white hairs. Older lower stems sometimes become brownish, woody-looking, and glabrous. Alternate leaves occur along the entire length of the stems, becoming gradually smaller in size as they ascend. These leaves are up to 5" long and ¾" across; they are narrowly lanceolate, elliptic, or elliptic-rhombic in shape, while their margins are entire (toothless) or sparingly serrated. Usually the lower to middle leaves have a few teeth along their middle to outer margins, while the upper leaves are entire. The leaves taper to acute tips, while their bases are wedge-shaped (cuneate); they are either sessile or taper gradually into short winged petioles. The upper leaf surface is medium to medium-dark green and glabrous, while the lower leaf surface is slightly more pale and usually glabrous (very young leaves may be sparsely short-pubescent below). A reticulated network of secondary veins is clearly visible on the lower side of each leaf, and sometimes it is also visible on the upper side. During cold autumn weather, sometimes the foliage becomes purple. The central stem terminates in a panicle of flowerheads up to 8" long and 4" across; smaller panicles of flowerheads are often produced from upper lateral stems and the axils of upper leaves.
Flowerheads, Leaves, & Leafy Bracts
The branches of these panicles are similar to the stems, except they tend to be more hairy and more grooved. Solitary leafy bracts up to 1½" long and 8 mm. across occur where these branches diverge, and they also occur at the bases of peduncles (basal stalks of the flowerheads). These peduncles are up to 1½" long. Each daisy-like flowerhead spans ½–¾" across, consisting of 20-40 ray florets that surround a dense head of numerous disk florets. The petaloid rays of a flowerhead are white and linear-oblong; when a flowerhead is fully open, they are widely spreading to somewhat declined. The corollas of disk florets 3-5 mm. long, tubular in shape, and 5-lobed along their rims; they are initially yellow, but later become orange-red. The lobes of the corollas are triangular in shape and ascending to widely spreading. The ray florets are fertile and pistillate, while the disk florets are fertile and perfect. Surrounding the base of each flowerhead, there are numerous phyllaries (scale-like floral bracts) in several series that are erect to ascending. The phyllaries are 2-4 mm. long, light to medium green, linear-oblong in shape, and glabrous. The blooming period occurs from late summer into autumn for 1-2 months. Afterwards, the florets are replaced by achenes with small tufts of white hair; they are dispersed by the wind. The achenes are about 1.5–2 mm. long, gray to dark gray, narrowly oblanceoloid in shape, slightly flattened, and finely pubescent. The root system is fibrous and long-rhizomatous. Clonal colonies of plants are often produced from the rhizomes.
Cultivation: The preference is full to partial sun and moist conditions. Favored locations are poorly drained areas that form pools of water temporarily, but later dry out. This plant can tolerate average levels of moisture and some drought, but it won't grow as large and its lower leaves may shrivel away. The soil can contain loam, clay, gravel, or even large rocks – this plant doesn't seem to care. Some foliar disease may occur, such as patches of rust or powdery mildew, but the foliage is usually in good shape during the blooming period of autumn. In damp open areas, this plant may spread aggressively by means of its rhizomes.
Range & Habitat: The native Panicled Aster occurs in most counties of Illinois (see Distribution Map), where it is common. Habitats include disturbed areas of moist prairies, prairie swales, openings and edges of floodplain woodlands, moist meadows along rivers, thickets, gravelly seeps, low areas along ponds and small lakes, edges of marshes, seasonal wetlands, roadside ditches, poorly drained gravelly areas of junkyards, fence rows, pastures, and abandoned fields. This plant often thrives in moist disturbed areas that are subjected to little or no mowing.
Faunal Associations: The nectar and pollen of the flowerheads attract many kinds of insects, including honeybees, bumblebees, leaf-cutting bees (Megachile spp.), Halictid bees (including green metallic bees), Halictid cuckoo bees (Sphecodes spp.), oligolectic Andrenid bees (Andrena spp.), Crabonid wasps (Ectemnius spp. & others), bee wolves (Philanthus spp.), thread-waisted wasps (Ammophila spp.), paper wasps (Polistes spp.), Eumenine wasps, Ichneumonid wasps, Syrphid flies, bee flies (Bombyliidae), Tachinid flies, flesh flies (Helicobia spp. & others), bottle flies (Lucilia spp.), Muscid flies, butterflies (Vanessa spp. & others), skippers, and beetles. Other insects feed destructively on the leaves and other parts of the Panicled Aster (Aster lanceolatus). These species include the leaf beetles Microrhopala xerene, Ophraella pilosa, Paria thoracia, and Sumitrosis inaequalis; larvae of the leaf-mining flies Nemorimyza posticata, Ophiomyia texana, and Phytomyza albiceps; larvae of Asteromyia laeviana (Papery Blister-Gall Midge) and the gall fly Rhopalomyia asteriflorae; the aphid Uroleucon olivei; and caterpillars of a butterfly, Phyciodes tharos (Pearl Crescent); see Clark et al. (2004), Needham et al. (1928), Felt (1917), Blackman & Eastop (2013), and Opler & Krizek (1984). Other insects that feed on this aster and other asters (Symphyotrichum spp.) include the larvae of fruit flies, plant bugs, several aphids, grasshoppers, and the larvae of many moths. Vertebrate animals also use asters as a source of food. The Ruffed Grouse and Wild Turkey feed on the seeds and foliage of these plants, while the Tree Sparrow and White-footed Mouse feed on the seeds only. Mammalian herbivores also browse on the foliage of asters, including deer, rabbits, groundhogs, horses, cattle, and sheep. In particular, White-Tailed Deer are very fond of the foliage of Panicled Aster, browsing its leafy stems to within inches of the ground (Martin et al., 1951/1961; personal observations).
Photographic Location: The photographs were taken at a rock-filled ditch near Urbana, Illinois.
Comments: Panicled Aster (Symphyotrichum lanceolatum) is rather showy when it is in bloom, even though it is often treated as an undesirable weed. This aster can be difficult to distinguish from other asters (Symphyotrichum spp.) that have small flowerheads with white petaloid rays. It has several characteristics that, when they are taken together, are useful in making a correct identification: 1) its flowerheads are usually ½" across or slightly more, 2) its flowerheads have at least 20 ray florets, 3) its leaves have wedged-shaped bases, rather than rounded or cordate (heart-shaped), 4) its mature leaves are hairless on both their upper and lower sides, 5) its stems usually have lines of fine white hairs, and 6) its panicles of flowerheads have conspicuous leafy bracts. Regarding nomenclature, alternative common names for this plant are 'Tall White Aster' and 'White Field Aster,' while older scientific names include Aster lanceolatus, Aster paniculatus and Aster simplex.
Flowerheads, Leaves, & Leafy Bracts
The branches of these panicles are similar to the stems, except they tend to be more hairy and more grooved. Solitary leafy bracts up to 1½" long and 8 mm. across occur where these branches diverge, and they also occur at the bases of peduncles (basal stalks of the flowerheads). These peduncles are up to 1½" long. Each daisy-like flowerhead spans ½–¾" across, consisting of 20-40 ray florets that surround a dense head of numerous disk florets. The petaloid rays of a flowerhead are white and linear-oblong; when a flowerhead is fully open, they are widely spreading to somewhat declined. The corollas of disk florets 3-5 mm. long, tubular in shape, and 5-lobed along their rims; they are initially yellow, but later become orange-red. The lobes of the corollas are triangular in shape and ascending to widely spreading. The ray florets are fertile and pistillate, while the disk florets are fertile and perfect. Surrounding the base of each flowerhead, there are numerous phyllaries (scale-like floral bracts) in several series that are erect to ascending. The phyllaries are 2-4 mm. long, light to medium green, linear-oblong in shape, and glabrous. The blooming period occurs from late summer into autumn for 1-2 months. Afterwards, the florets are replaced by achenes with small tufts of white hair; they are dispersed by the wind. The achenes are about 1.5–2 mm. long, gray to dark gray, narrowly oblanceoloid in shape, slightly flattened, and finely pubescent. The root system is fibrous and long-rhizomatous. Clonal colonies of plants are often produced from the rhizomes.
Cultivation: The preference is full to partial sun and moist conditions. Favored locations are poorly drained areas that form pools of water temporarily, but later dry out. This plant can tolerate average levels of moisture and some drought, but it won't grow as large and its lower leaves may shrivel away. The soil can contain loam, clay, gravel, or even large rocks – this plant doesn't seem to care. Some foliar disease may occur, such as patches of rust or powdery mildew, but the foliage is usually in good shape during the blooming period of autumn. In damp open areas, this plant may spread aggressively by means of its rhizomes.
Range & Habitat: The native Panicled Aster occurs in most counties of Illinois (see Distribution Map), where it is common. Habitats include disturbed areas of moist prairies, prairie swales, openings and edges of floodplain woodlands, moist meadows along rivers, thickets, gravelly seeps, low areas along ponds and small lakes, edges of marshes, seasonal wetlands, roadside ditches, poorly drained gravelly areas of junkyards, fence rows, pastures, and abandoned fields. This plant often thrives in moist disturbed areas that are subjected to little or no mowing.
Faunal Associations: The nectar and pollen of the flowerheads attract many kinds of insects, including honeybees, bumblebees, leaf-cutting bees (Megachile spp.), Halictid bees (including green metallic bees), Halictid cuckoo bees (Sphecodes spp.), oligolectic Andrenid bees (Andrena spp.), Crabonid wasps (Ectemnius spp. & others), bee wolves (Philanthus spp.), thread-waisted wasps (Ammophila spp.), paper wasps (Polistes spp.), Eumenine wasps, Ichneumonid wasps, Syrphid flies, bee flies (Bombyliidae), Tachinid flies, flesh flies (Helicobia spp. & others), bottle flies (Lucilia spp.), Muscid flies, butterflies (Vanessa spp. & others), skippers, and beetles. Other insects feed destructively on the leaves and other parts of the Panicled Aster (Aster lanceolatus). These species include the leaf beetles Microrhopala xerene, Ophraella pilosa, Paria thoracia, and Sumitrosis inaequalis; larvae of the leaf-mining flies Nemorimyza posticata, Ophiomyia texana, and Phytomyza albiceps; larvae of Asteromyia laeviana (Papery Blister-Gall Midge) and the gall fly Rhopalomyia asteriflorae; the aphid Uroleucon olivei; and caterpillars of a butterfly, Phyciodes tharos (Pearl Crescent); see Clark et al. (2004), Needham et al. (1928), Felt (1917), Blackman & Eastop (2013), and Opler & Krizek (1984). Other insects that feed on this aster and other asters (Symphyotrichum spp.) include the larvae of fruit flies, plant bugs, several aphids, grasshoppers, and the larvae of many moths. Vertebrate animals also use asters as a source of food. The Ruffed Grouse and Wild Turkey feed on the seeds and foliage of these plants, while the Tree Sparrow and White-footed Mouse feed on the seeds only. Mammalian herbivores also browse on the foliage of asters, including deer, rabbits, groundhogs, horses, cattle, and sheep. In particular, White-Tailed Deer are very fond of the foliage of Panicled Aster, browsing its leafy stems to within inches of the ground (Martin et al., 1951/1961; personal observations).
Photographic Location: The photographs were taken at a rock-filled ditch near Urbana, Illinois.
Comments: Panicled Aster (Symphyotrichum lanceolatum) is rather showy when it is in bloom, even though it is often treated as an undesirable weed. This aster can be difficult to distinguish from other asters (Symphyotrichum spp.) that have small flowerheads with white petaloid rays. It has several characteristics that, when they are taken together, are useful in making a correct identification: 1) its flowerheads are usually ½" across or slightly more, 2) its flowerheads have at least 20 ray florets, 3) its leaves have wedged-shaped bases, rather than rounded or cordate (heart-shaped), 4) its mature leaves are hairless on both their upper and lower sides, 5) its stems usually have lines of fine white hairs, and 6) its panicles of flowerheads have conspicuous leafy bracts. Regarding nomenclature, alternative common names for this plant are 'Tall White Aster' and 'White Field Aster,' while older scientific names include Aster lanceolatus, Aster paniculatus and Aster simplex.
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Miss Chen
2018年02月22日
Description: This perennial plant is 1½–3' tall and more or less erect. It is usually unbranched below, while branching occasionally above. The stems are light green or light blue, glabrous, and often glaucous; they are usually terete, although sometimes the stems are narrowly furrowed. Alternate leaves occur along the entire length of these stems, becoming gradually smaller in size as they ascend. These leaves are up to 6" long and 1¼" across, although they are typically about one-half of this size. The leaves are oblong-ovate, oblong-obovate, lanceolate, or ovate in shape, while their margins are either entire (toothless) or sparingly and bluntly toothed. Both lower and upper leaves clasp their stems. The upper leaf surface is medium green to grayish blue, glabrous, and sometimes glaucous, while the lower leaf surface is light green or light grayish blue, glabrous, and sometimes glaucous. A reticulated network of secondary veins is usually visible on the lower surface of each leaf.
The central stem terminates in a panicle of flowerheads about ½–1' long and about one-half as much across; smaller panicles of flowers often develop from lateral upper stems and the axils of upper leaves. Each flowerhead is ½–1" across, consisting of 15-30 ray florets that surround a dense head of numerous disk florets. The petaloid rays of the flowerheads are light lavender or light blue-violet (rarely white), widely spreading, and narrowly oblong in shape. The corollas of the disk florets are 3-6 mm. long, tubular in shape, and 5-lobed along their upper rims. During the blooming period, they change in color from whitish yellow to purplish red, eventually turning brown afterwards. The short-triangular lobes of these corollas are erect or ascending. Surrounding the base of each flowerhead, there are glabrous phyllaries (floral bracts) in several series that are erect or appressed together; they are linear-oblong in shape or sometimes wider. These phyllaries are mostly light green or light bluish green; they have either dark green markings at their tips or solitary vertical veins that are dark green.
The branches and peduncles of the panicle are light green or light grayish blue, terete, glabrous, and sometimes glaucous; solitary leafy bracts up to 2" long and ½" occur where the branches divide. The characteristics of these leafy bracts are similar to those of the leaves. The blooming period occurs from late summer to early autumn, lasting about 3-4 weeks for a colony of plants. Afterwards, the florets are replaced by achenes with small tufts of tawny (less often white) hair; they are distributed by the wind. Individual achenes are 2-3 mm. long, narrowly oblongoid-oblanceoloid in shape, slightly flattened, and variably colored (usually some shade of gray or brown with whitish fine ribs). The root system is fibrous and rhizomatous; older plants may develop small woody caudices. Occasionally, clonal offsets are produced from the rhizomes.
Cultivation: The preference is full to partial sun, mesic conditions, and soil containing loam, clay-loam, sandy loam, or some rocky material. This plant usually remains erect while in bloom and it is able to tolerate hot dry weather if it is not too prolonged. The foliage is occasional marred by powdery mildew and other foliar diseases to some extent; good air circulation reduces this vulnerability. Smooth Blue Aster is easy to cultivate in gardens if taller and more aggressive plants are kept away from it.
Range & Habitat: The native Smooth Blue Aster occurs occasionally in most counties of Illinois, but it is uncommon or absent in western and SE Illinois (see Distribution Map). Habitats include mesic black soil prairies, hill prairies, savannas, rocky open woodlands, sandy woodlands, woodland edges, thickets, limestone glades, and roadside embankments. Smooth Blue Aster is usually found in higher quality natural areas where the original ground flora is intact. It is sometimes cultivated in gardens because of its attractive foliage and flowerheads.
Faunal Associations: The nectar and pollen of the flowerheads attract honeybees, bumblebees, cuckoo bees (Triepeolus spp., Coelioxys spp.), digger bees (Melissodes spp.), leaf-cutting bees (Megachile spp.), Halictid bees (Agapostemon spp., Halictus spp., Lasioglossum spp.), Andrenid bees (including the oligolectic bee, Andrena asteris), Sphecid wasps, Syrphid flies (Eristalis spp., Helophilus spp., Syrphus spp., Toxomerus spp.), Muscid flies, butterflies, and skippers (see Graenicher). Other insects feed destructively on the leaves, flowerheads, and other parts of Smooth Blue Aster. These species include a leaf beetle (Ophraella pilosa), larvae of a leaf-mining fly (Nemorimyza posticata), larvae of the Papery Blister Gall Midge (Asteromyia laeviana), the Short-winged Meadow Katydid (Conocephalus brevipennis), and caterpillars of a butterfly, the Pearl Crescent (Phyciodes tharos); see Clark et al. (2004), Needham et al. (1928), Felt (1917), Gangwere (1961), and Opler & Krizek (1984). The Insect Table and Moth Table list additional insects that feed on this and other asters (Symphyotrichum spp.). Two upland gamebirds, the Ruffed Grouse and Wild Turkey, feed on both the leaves and seeds of asters. The Tree Sparrow and White-footed Mouse also eat the seeds. The young foliage of these plants is browsed occasionally by various mammalian herbivores, including deer, rabbits, groundhogs, horses, cattle, and sheep.
Photographic Location: The photographs were taken at a restored prairie of Meadowbrook Park in Urbana, Illinois, and at a small restored prairie along a drainage ditch in the same city.
Comments: Smooth Blue Aster (Symphyotrichum laeve) has many attractive qualities – they include its adaptability, beautiful flowerheads, attractive foliage, and flowering stems that usually remain erect. It's surprising that this aster is not grown more often in flower gardens. Smooth Blue Aster can be distinguished from other asters (Symphyotrichum spp.) primarily by the lack of hairs on its smooth foliage and stems; its foliage often has grayish or bluish tints. Other asters tend to have leaves that are hairy or rough-textured, while others have stems with lines of hair. Another distinctive characteristic is the lack of petioles – the leaves of Smooth Blue Aster clasp their stems. A scientific synonym of this plant is Aster laevis.
The central stem terminates in a panicle of flowerheads about ½–1' long and about one-half as much across; smaller panicles of flowers often develop from lateral upper stems and the axils of upper leaves. Each flowerhead is ½–1" across, consisting of 15-30 ray florets that surround a dense head of numerous disk florets. The petaloid rays of the flowerheads are light lavender or light blue-violet (rarely white), widely spreading, and narrowly oblong in shape. The corollas of the disk florets are 3-6 mm. long, tubular in shape, and 5-lobed along their upper rims. During the blooming period, they change in color from whitish yellow to purplish red, eventually turning brown afterwards. The short-triangular lobes of these corollas are erect or ascending. Surrounding the base of each flowerhead, there are glabrous phyllaries (floral bracts) in several series that are erect or appressed together; they are linear-oblong in shape or sometimes wider. These phyllaries are mostly light green or light bluish green; they have either dark green markings at their tips or solitary vertical veins that are dark green.
The branches and peduncles of the panicle are light green or light grayish blue, terete, glabrous, and sometimes glaucous; solitary leafy bracts up to 2" long and ½" occur where the branches divide. The characteristics of these leafy bracts are similar to those of the leaves. The blooming period occurs from late summer to early autumn, lasting about 3-4 weeks for a colony of plants. Afterwards, the florets are replaced by achenes with small tufts of tawny (less often white) hair; they are distributed by the wind. Individual achenes are 2-3 mm. long, narrowly oblongoid-oblanceoloid in shape, slightly flattened, and variably colored (usually some shade of gray or brown with whitish fine ribs). The root system is fibrous and rhizomatous; older plants may develop small woody caudices. Occasionally, clonal offsets are produced from the rhizomes.
Cultivation: The preference is full to partial sun, mesic conditions, and soil containing loam, clay-loam, sandy loam, or some rocky material. This plant usually remains erect while in bloom and it is able to tolerate hot dry weather if it is not too prolonged. The foliage is occasional marred by powdery mildew and other foliar diseases to some extent; good air circulation reduces this vulnerability. Smooth Blue Aster is easy to cultivate in gardens if taller and more aggressive plants are kept away from it.
Range & Habitat: The native Smooth Blue Aster occurs occasionally in most counties of Illinois, but it is uncommon or absent in western and SE Illinois (see Distribution Map). Habitats include mesic black soil prairies, hill prairies, savannas, rocky open woodlands, sandy woodlands, woodland edges, thickets, limestone glades, and roadside embankments. Smooth Blue Aster is usually found in higher quality natural areas where the original ground flora is intact. It is sometimes cultivated in gardens because of its attractive foliage and flowerheads.
Faunal Associations: The nectar and pollen of the flowerheads attract honeybees, bumblebees, cuckoo bees (Triepeolus spp., Coelioxys spp.), digger bees (Melissodes spp.), leaf-cutting bees (Megachile spp.), Halictid bees (Agapostemon spp., Halictus spp., Lasioglossum spp.), Andrenid bees (including the oligolectic bee, Andrena asteris), Sphecid wasps, Syrphid flies (Eristalis spp., Helophilus spp., Syrphus spp., Toxomerus spp.), Muscid flies, butterflies, and skippers (see Graenicher). Other insects feed destructively on the leaves, flowerheads, and other parts of Smooth Blue Aster. These species include a leaf beetle (Ophraella pilosa), larvae of a leaf-mining fly (Nemorimyza posticata), larvae of the Papery Blister Gall Midge (Asteromyia laeviana), the Short-winged Meadow Katydid (Conocephalus brevipennis), and caterpillars of a butterfly, the Pearl Crescent (Phyciodes tharos); see Clark et al. (2004), Needham et al. (1928), Felt (1917), Gangwere (1961), and Opler & Krizek (1984). The Insect Table and Moth Table list additional insects that feed on this and other asters (Symphyotrichum spp.). Two upland gamebirds, the Ruffed Grouse and Wild Turkey, feed on both the leaves and seeds of asters. The Tree Sparrow and White-footed Mouse also eat the seeds. The young foliage of these plants is browsed occasionally by various mammalian herbivores, including deer, rabbits, groundhogs, horses, cattle, and sheep.
Photographic Location: The photographs were taken at a restored prairie of Meadowbrook Park in Urbana, Illinois, and at a small restored prairie along a drainage ditch in the same city.
Comments: Smooth Blue Aster (Symphyotrichum laeve) has many attractive qualities – they include its adaptability, beautiful flowerheads, attractive foliage, and flowering stems that usually remain erect. It's surprising that this aster is not grown more often in flower gardens. Smooth Blue Aster can be distinguished from other asters (Symphyotrichum spp.) primarily by the lack of hairs on its smooth foliage and stems; its foliage often has grayish or bluish tints. Other asters tend to have leaves that are hairy or rough-textured, while others have stems with lines of hair. Another distinctive characteristic is the lack of petioles – the leaves of Smooth Blue Aster clasp their stems. A scientific synonym of this plant is Aster laevis.
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Miss Chen
2018年02月22日
Description: This herbaceous perennial plant is up to 2' tall, branching occasionally to create a bushy appearance. The hairy stems are green initially, but often become brown when the plant matures. The alternate leaves are up to 3" long and ¼" across toward the base of the plant, becoming less than 1" long and 1/8" (3 mm.) across near the flowering stems. They are linear in form and have smooth edges, often with a fine pubescence. The lower leaves usually shrivel and fall off by the time the compound flowers bloom during the fall. These flowers are very numerous and have a daisy-like appearance. Each compound flower is a little less than ½" across, and consists of numerous yellow disk florets, which are surrounded by about 12 white ray florets. There is no noticeable floral scent. There are numerous needle-like green bracts on the flowering stems, giving this plant a heath-like appearance. The little seeds have tufts of white hairs, and are distributed by the wind. The root system is rhizomatous.
Cultivation: The preference is full sun and average to dry conditions. The soil can contain significant amounts of loam, clay, or gravelly material; alkaline soil is tolerated. This plant withstands drought. It often spreads vegetatively to form colonies, especially in open disturbed areas.
Range & Habitat: The native Heath Aster is found in most counties of Illinois, but it is absent from some counties in the western and SE areas of the state (see Distribution Map). Overall, it is occasional to locally common. Habitats include mesic to dry black soil prairies, gravel prairies, dolomite prairies, hill prairies, savannas, openings in dry rocky forests, limestone glades, areas along roadsides and railroads, and pastures. It can be found in both high quality habitats and disturbed areas.
Faunal Associations: A wide variety of insects are attracted to the flowers, including long-tongued bees, short-tongued bees, wasps, flies, butterflies, skippers, moths, beetles, and plant bugs. Bee visitors include honeybees, bumblebees, cuckoo bees, little carpenter bees, leaf-cutting bees, Halictid bees, plasterer bees, and Andrenid bees. Wasp visitors include thread-waisted wasps, bee wolves, spider wasps, sand wasps, paper wasps, Ichneumonid wasps, and Braconid wasps. Among the flies, are such visitors as bee flies, Syrphid flies, thick-headed flies, Tachinid flies, Muscid flies, and others. Various insects suck juices from the plant, including aphids, lace bugs, and plant bugs. The caterpillars of the butterfly Chlosyne nycteis (Silvery Checkerspot) feed on the foliage or flowers, as does the caterpillars of many moth species (see Moth Table). Wild Turkeys nibble on the seeds and foliage to a limited extent. Mammalian herbivores, including the White-Tailed Deer, Cottontail Rabbit, and various kinds of livestock, also feed on the tender growth of young plants occasionally, but are less likely to bother mature plants later in the year.
Photographic Location: The photographs were taken at Loda Cemetery Prairie in Iroquois County, Illinois.
Comments: The Heath Aster has a wide distribution, and there is some variability in regards to its size and appearance across different locations. Sometimes it will hybridize with other species of asters, such as Symphyotrichum novae-angliae. The Heath Aster differs from other asters with small white flowerheads primarily by its short, narrow leaves (never more than 3" long and ¼" across). Also, its flowerheads tend to be smaller in size and they have fewer ray florets (about 12) than many other aster species. A scientific synonym of this plant is Aster ericoides.
Cultivation: The preference is full sun and average to dry conditions. The soil can contain significant amounts of loam, clay, or gravelly material; alkaline soil is tolerated. This plant withstands drought. It often spreads vegetatively to form colonies, especially in open disturbed areas.
Range & Habitat: The native Heath Aster is found in most counties of Illinois, but it is absent from some counties in the western and SE areas of the state (see Distribution Map). Overall, it is occasional to locally common. Habitats include mesic to dry black soil prairies, gravel prairies, dolomite prairies, hill prairies, savannas, openings in dry rocky forests, limestone glades, areas along roadsides and railroads, and pastures. It can be found in both high quality habitats and disturbed areas.
Faunal Associations: A wide variety of insects are attracted to the flowers, including long-tongued bees, short-tongued bees, wasps, flies, butterflies, skippers, moths, beetles, and plant bugs. Bee visitors include honeybees, bumblebees, cuckoo bees, little carpenter bees, leaf-cutting bees, Halictid bees, plasterer bees, and Andrenid bees. Wasp visitors include thread-waisted wasps, bee wolves, spider wasps, sand wasps, paper wasps, Ichneumonid wasps, and Braconid wasps. Among the flies, are such visitors as bee flies, Syrphid flies, thick-headed flies, Tachinid flies, Muscid flies, and others. Various insects suck juices from the plant, including aphids, lace bugs, and plant bugs. The caterpillars of the butterfly Chlosyne nycteis (Silvery Checkerspot) feed on the foliage or flowers, as does the caterpillars of many moth species (see Moth Table). Wild Turkeys nibble on the seeds and foliage to a limited extent. Mammalian herbivores, including the White-Tailed Deer, Cottontail Rabbit, and various kinds of livestock, also feed on the tender growth of young plants occasionally, but are less likely to bother mature plants later in the year.
Photographic Location: The photographs were taken at Loda Cemetery Prairie in Iroquois County, Illinois.
Comments: The Heath Aster has a wide distribution, and there is some variability in regards to its size and appearance across different locations. Sometimes it will hybridize with other species of asters, such as Symphyotrichum novae-angliae. The Heath Aster differs from other asters with small white flowerheads primarily by its short, narrow leaves (never more than 3" long and ¼" across). Also, its flowerheads tend to be smaller in size and they have fewer ray florets (about 12) than many other aster species. A scientific synonym of this plant is Aster ericoides.
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Miss Chen
2018年02月22日
Description: This herbaceous perennial plant is ½–2½' tall and usually unbranched. The central stem is 4-angled, usually with scattered hairs along the ridges, but not the sides (see Stem Photo). The opposite leaves are up to 3½" long and 1"Whorls of Flowers across. They are usually lanceolate or narrowly ovate, with serrate or crenate margins. The petioles of the lower leaves are about ¼" or slightly longer, while the upper leaves have shorter petioles or are sessile. Both the upper and lower surfaces of the leaves are hairless or nearly so – if hairs are present, they are most likely to occur along the lower mid-vein of the leaves. The central stem terminates in a spike-like inflorescence that has whorls of flowers at intervals along its length. This inflorescence can vary from 2-8" in length. The tubular corolla of each flower is about 1/3" long and divided into 2 lips. The hairy upper lip functions as a protective hood, while the lower lip is divided into 3 lobes (a central lobe and two smaller side lobes), which functions as a landing pad for visiting insects. The flowers are light pink or white, often with rosy pink splotches within the throat. The green calyx is hairless and at least half as long as the tube of the corolla (not including the lips). It is divided into 5 triangular segments that curl outward as the ovaries mature. The blooming period occurs during the summer and lasts about 1-2 months. Each flower is replaced by 4 black nutlets that are oblong in shape. The root system consists of a taproot and rhizomes. This plant often forms vegetative colonies, like many other members of the Mint family.
Cultivation: The preference is partial sun and moist conditions. This plant also tolerates light shade and full sun. The soil should contain sufficient organic material to retain moisture. If this plant dries out, the leaves have a tendency to turn yellow or brown, and the entire plant may die.
Range & Habitat: Smooth Hedge Nettle occurs in most counties of Illinois (see Distribution Map), where it is native. This plant is occasional in southern and central Illinois, but uncommon or absent in the northern counties. Habitats include ravines in floodplain forests, moist meadows along rivers or woodlands, thickets, and various kinds of wetlands, including swamps, seeps, and ditches. It can be found in either high quality habitats or rather degraded sites.
Faunal Associations: Primarily long-tongued bees pollinate the flowers, where they seek nectar primarily. Short-tongued bees sometimes collect pollen, while flower flies feed on the pollen, but they are not very effective pollinators. Occasionally butterflies or skippers may visit the flowers, but they aren't very effective at pollinating the flowers either. The bitter foliage of this and other Stachys spp. is not often consumed by mammalian herbivores.
Photographic Location: A swampy area of Busey Woods in Urbana, Illinois.
Comments: This is a typical member of the Mint family. It is easy to overlook, because this Hedge Nettle sp. tends to be rather small-sized and non-descript, almost looking like a lanky Prunella vulgaris (Self-Heal) at first glance. Identifying Smooth Hedge Nettle correctly can be rather tricky, so here are some of the key features to look for: 1) The calyx is hairless; 2) the petioles of the lower leaves are usually ¼" or longer, and 3) there are hairs on the ridges of the 4-angled central stem, but not on the sides. There is also a hairy form of this plant, referred to as Stachys tenuifolia hispida by some authorities and Stachys hispida by others, that also occurs in Illinois. It has foliage that is more hairy, and there are also some hairs along the edges of the calyx of each flower. However, it is similar to Smooth Hedge Nettle in that the central stem has hairs along the ridges, but not on the sides.
Cultivation: The preference is partial sun and moist conditions. This plant also tolerates light shade and full sun. The soil should contain sufficient organic material to retain moisture. If this plant dries out, the leaves have a tendency to turn yellow or brown, and the entire plant may die.
Range & Habitat: Smooth Hedge Nettle occurs in most counties of Illinois (see Distribution Map), where it is native. This plant is occasional in southern and central Illinois, but uncommon or absent in the northern counties. Habitats include ravines in floodplain forests, moist meadows along rivers or woodlands, thickets, and various kinds of wetlands, including swamps, seeps, and ditches. It can be found in either high quality habitats or rather degraded sites.
Faunal Associations: Primarily long-tongued bees pollinate the flowers, where they seek nectar primarily. Short-tongued bees sometimes collect pollen, while flower flies feed on the pollen, but they are not very effective pollinators. Occasionally butterflies or skippers may visit the flowers, but they aren't very effective at pollinating the flowers either. The bitter foliage of this and other Stachys spp. is not often consumed by mammalian herbivores.
Photographic Location: A swampy area of Busey Woods in Urbana, Illinois.
Comments: This is a typical member of the Mint family. It is easy to overlook, because this Hedge Nettle sp. tends to be rather small-sized and non-descript, almost looking like a lanky Prunella vulgaris (Self-Heal) at first glance. Identifying Smooth Hedge Nettle correctly can be rather tricky, so here are some of the key features to look for: 1) The calyx is hairless; 2) the petioles of the lower leaves are usually ¼" or longer, and 3) there are hairs on the ridges of the 4-angled central stem, but not on the sides. There is also a hairy form of this plant, referred to as Stachys tenuifolia hispida by some authorities and Stachys hispida by others, that also occurs in Illinois. It has foliage that is more hairy, and there are also some hairs along the edges of the calyx of each flower. However, it is similar to Smooth Hedge Nettle in that the central stem has hairs along the ridges, but not on the sides.
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Miss Chen
2018年02月22日
Description: This perennial plant is about 1½-3' tall and either unbranched or sparingly so. The 4-angled central stem is light green to dark purple and covered with fine hairs on all sides. The opposite leaves are up to 4" long and 1¾" across. They are lanceolate-oblong to ovate-oblong in shape, finely serrated along their margins, and either sessile against the stem or with short petioles (less than 1/3" or 8 mm. in length). The upper leaf surface is medium to dark green and finely short-hairy, while the lower surface is light green and finely hairy, especially along the lower sides of major veins. The foliage has an unpleasant bitter smell. The central stem terminates in a spike of flowers about 4-8" long. This spike consists of about 4-12 whorls of flowers, each whorl having several flowers. Each flower is about ½" long, consisting of a short-tubular corolla with 2 lips, a short-tubular calyx with 5 narrow triangular teeth, and the inserted reproductive organs. The corolla is white to light pink with splotches of rosy pink. The upper lip of the corolla is undivided and hairy along its upper surface, while the lower lip is divided into 3 lobes (a central lobe and 2 smaller side lobes). The calyx is green to purplish green and finely hairy. The calyx is green or purplish green; its teeth extend to more than one-half of the length of the corolla tube (excluding the length of the lips). The central stalk of the floral spike is green to dark purple and covered with fine hairs on all sides. The blooming period occurs during the summer and lasts about 1-2 months. Sometimes the flowers have a mild fragrance.
After the blooming period, the flowers are replaced by open seed capsules; each capsule contains 4 small nutlets. The root system is rhizomatous and tuberous. Hairy Hedge Nettle often forms clonal colonies of varying size.
Cultivation: The preference is full sun to light shade, moist conditions, and soil that is loamy or sandy. The foliage is rarely bothered by either disease or insects.
Range & Habitat: The native Hairy Hedge Nettle occurs primarily in central and northern Illinois, where it is occasional. In southern Illinois, it is either absent or uncommon (see Distribution Map). Habitats include moist prairies, edges of marshes, moist meadows in wooded areas, borders of bottomland woodlands, soggy thickets, prairie swales, roadside ditches, edges of fields, and fence rows. Hairy Hedge Nettle can occur in either sandy or non-sandy habitats that are variable in their level of disturbance.
Faunal Associations: The flowers are visited by nectar-seeking bees primarily, including bumblebees, leaf-cutting bees (Megachile spp.), digger bees (Melissodes spp.), little carpenter bees (Ceratina spp.), and Anthophorid bees (Anthophora spp.). Sometimes the flowers are visited by butterflies, skippers, and moths, but they are not very effective at cross-pollination. Small bees also visit the flowers to collect pollen. The seeds of Stachys spp. (Hedge Nettles) and other members of the Mint family are eaten by Sehirus cinctus (White-Margined Burrower Bug). Because the foliage is bitter and hairy, it is not favored as a food source by mammalian herbivores.
Photographic Location: The photograph was taken in an overgrown moist area between an abandoned railroad and a roadside in Champaign County, Illinois.
Comments: This plant has an unsettled taxonomic history. At the present time, I prefer to use the scientific name Stachys palustris arenicola from the Field Guide to Indiana Wildflowers (2000) by Kay Yatskievych. Older authorities, such as A. G. Jones or Britton & Brown, called this species Stachys arenicola. In contrast, Mohlenbrock (1986, 2002) probably refers to this species as a variety of Stachys palustris or Stachys pilosa. Hairy Hedge Nettle can be distinguished from other Stachys spp. (Hedge Nettles) by the presence of fine hairs on all 4 sides of its central stem, the general hairiness of its leaves, the absence of petioles exceeding 1/3" (8 mm.) in length, the length of its toothed calyx in relation to the corolla tube (exceeding one-half of its length), and the shape of its calyx teeth. All of the Hedge Nettles differ from the similar Teucrium canadense (American Germander) by having flowers with well-defined upper lips.
After the blooming period, the flowers are replaced by open seed capsules; each capsule contains 4 small nutlets. The root system is rhizomatous and tuberous. Hairy Hedge Nettle often forms clonal colonies of varying size.
Cultivation: The preference is full sun to light shade, moist conditions, and soil that is loamy or sandy. The foliage is rarely bothered by either disease or insects.
Range & Habitat: The native Hairy Hedge Nettle occurs primarily in central and northern Illinois, where it is occasional. In southern Illinois, it is either absent or uncommon (see Distribution Map). Habitats include moist prairies, edges of marshes, moist meadows in wooded areas, borders of bottomland woodlands, soggy thickets, prairie swales, roadside ditches, edges of fields, and fence rows. Hairy Hedge Nettle can occur in either sandy or non-sandy habitats that are variable in their level of disturbance.
Faunal Associations: The flowers are visited by nectar-seeking bees primarily, including bumblebees, leaf-cutting bees (Megachile spp.), digger bees (Melissodes spp.), little carpenter bees (Ceratina spp.), and Anthophorid bees (Anthophora spp.). Sometimes the flowers are visited by butterflies, skippers, and moths, but they are not very effective at cross-pollination. Small bees also visit the flowers to collect pollen. The seeds of Stachys spp. (Hedge Nettles) and other members of the Mint family are eaten by Sehirus cinctus (White-Margined Burrower Bug). Because the foliage is bitter and hairy, it is not favored as a food source by mammalian herbivores.
Photographic Location: The photograph was taken in an overgrown moist area between an abandoned railroad and a roadside in Champaign County, Illinois.
Comments: This plant has an unsettled taxonomic history. At the present time, I prefer to use the scientific name Stachys palustris arenicola from the Field Guide to Indiana Wildflowers (2000) by Kay Yatskievych. Older authorities, such as A. G. Jones or Britton & Brown, called this species Stachys arenicola. In contrast, Mohlenbrock (1986, 2002) probably refers to this species as a variety of Stachys palustris or Stachys pilosa. Hairy Hedge Nettle can be distinguished from other Stachys spp. (Hedge Nettles) by the presence of fine hairs on all 4 sides of its central stem, the general hairiness of its leaves, the absence of petioles exceeding 1/3" (8 mm.) in length, the length of its toothed calyx in relation to the corolla tube (exceeding one-half of its length), and the shape of its calyx teeth. All of the Hedge Nettles differ from the similar Teucrium canadense (American Germander) by having flowers with well-defined upper lips.
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Miss Chen
2018年02月21日
Description: This perennial plant is usually 4-12" tall and unbranched. There is a rosette of 2-6 strap-like basal leaves that are individually about 3-8" long and 1/3" (8 mm.) across. They are linear to linear-oblanceolate with smooth margins, and usually wither away before the flowers bloom. On robust specimens, there may be 1 or 2 small leaves on the lower flowering stalk. The flowering stalk is up to 1' tall, with 6-12 flowers occurring on the upper half. These flowers are arranged on the stalk as intertwined double spirals – as a result, the individual spirals are not readily discernible. The flowering stalk is light green and covered more or less with white glandular hairs. At the base of each flower, there is a conspicuous green bract that is curved and narrowly ovate. Each flower is about 1/3" (8 mm.) long, consisting of 3Flowering Stalk white sepals and 3 white petals. The upper sepal and upper two petals are fused together and form a curved hood that curls upward at its tip, forming a small upper lip with 3 lobes. The lower petal has a prominent lip that hangs downward and has a crystalline appearance, while the lateral sepals are linear and non-spreading. Together, these sepals and petals form a tubular-shaped flower that nods downward. The blooming period can occur from late summer until the fall, and lasts about a month. There is usually a mild floral scent. Some plants may form cleistogamous flowers. Fertilized flowers are replaced by pods containing the tiny seeds, which are easily carried aloft by the wind. These pods may be capable of photosynthesis while they are green. The root system consists of a cluster of fleshy roots at the base of the plant that are finger-like in shape, and occasional rhizomes may be produced. This orchid can reproduce from the seeds of the flowers, or it may form offsets from rhizomes. Normal growth and development won't occur unless the root system forms an endomycorrhizal association with the appropriate species of fungus.
Cultivation: For most ecotypes of this orchid, the preference is full or partial sun and moist sandy soil. Some ecotypes appear to flourish in thin rocky soil that is rather dry. Taller, more aggressive plants can out-compete this orchid for the available light, so it prefers rather open ground vegetation. Starting plants from seed is quite difficult; on the other hand, this orchid is easier to transplant than most others. Cultivars of this orchid species are available from the mass horticultural market, while local ecotypes are next to impossible to obtain.
Range & Habitat: Nodding Ladies' Tresses occurs occasionally throughout Illinois, where it is native; for an orchid species, it is fairly common (see Distribution Map). Habitats include moist sand prairies, sandy savannas, areas adjacent to paths in sandy woodlands, shrubby bogs, sandy pannes near lakes, gravelly seeps, limestone glades, bluffs, sandy pits, ditches, and abandoned fields. This orchid typically occurs in somewhat disturbed areas of high quality habitats, and appears to respond positively to occasional wildfires. Individual plants are usually scattered about, rather than forming dense colonies.
Faunal Associations: Both long-tongued and short-tongued bees occasionally visit the flowers for nectar. The seeds are too small to be of any interest to birds. The foliage can be eaten by various mammalian herbivores, including rabbits, groundhogs, and deer, while the fleshy roots are probably eaten by pocket gophers when individual plants stray into drier areas.
Photographic Location: The photographed plant was growing in a sandy swale at the Indiana Dunes National Lakeshore in NW Indiana.
Comments: While rather small-sized, the bright white spike of flowers provides a striking contrast with the background vegetation and is fairly easy to spot. The individual flowers are attractive, particularly when they are viewed close-up; in particular, the lower lip has an intricate crystalline pattern that can vary significantly from flower to flower. Unlike the Ladies' Tresses orchids that form a single spiral of flowers, such as Spiranthes lacera (Slender Ladies' Tresses), the Nodding Ladies' Tresses falls into the group of Spiranthes spp. with double intertwined spirals that are difficult to discern because of the density of flowers on the spike. The Spiranthes spp. in this group are distinguished from each other primarily by considering the variation in the structure of their flowers and the shape of their leaves. Nodding Ladies' Tresses can be distinguished from these other species by the downward curve of its tubular flowers, providing them with a 'nodding' appearance.
Cultivation: For most ecotypes of this orchid, the preference is full or partial sun and moist sandy soil. Some ecotypes appear to flourish in thin rocky soil that is rather dry. Taller, more aggressive plants can out-compete this orchid for the available light, so it prefers rather open ground vegetation. Starting plants from seed is quite difficult; on the other hand, this orchid is easier to transplant than most others. Cultivars of this orchid species are available from the mass horticultural market, while local ecotypes are next to impossible to obtain.
Range & Habitat: Nodding Ladies' Tresses occurs occasionally throughout Illinois, where it is native; for an orchid species, it is fairly common (see Distribution Map). Habitats include moist sand prairies, sandy savannas, areas adjacent to paths in sandy woodlands, shrubby bogs, sandy pannes near lakes, gravelly seeps, limestone glades, bluffs, sandy pits, ditches, and abandoned fields. This orchid typically occurs in somewhat disturbed areas of high quality habitats, and appears to respond positively to occasional wildfires. Individual plants are usually scattered about, rather than forming dense colonies.
Faunal Associations: Both long-tongued and short-tongued bees occasionally visit the flowers for nectar. The seeds are too small to be of any interest to birds. The foliage can be eaten by various mammalian herbivores, including rabbits, groundhogs, and deer, while the fleshy roots are probably eaten by pocket gophers when individual plants stray into drier areas.
Photographic Location: The photographed plant was growing in a sandy swale at the Indiana Dunes National Lakeshore in NW Indiana.
Comments: While rather small-sized, the bright white spike of flowers provides a striking contrast with the background vegetation and is fairly easy to spot. The individual flowers are attractive, particularly when they are viewed close-up; in particular, the lower lip has an intricate crystalline pattern that can vary significantly from flower to flower. Unlike the Ladies' Tresses orchids that form a single spiral of flowers, such as Spiranthes lacera (Slender Ladies' Tresses), the Nodding Ladies' Tresses falls into the group of Spiranthes spp. with double intertwined spirals that are difficult to discern because of the density of flowers on the spike. The Spiranthes spp. in this group are distinguished from each other primarily by considering the variation in the structure of their flowers and the shape of their leaves. Nodding Ladies' Tresses can be distinguished from these other species by the downward curve of its tubular flowers, providing them with a 'nodding' appearance.
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