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Miss Chen
2018年02月24日
Miss Chen
Description: This perennial wildflower is 1-2' tall, sending up one or more stems from the base that are unbranched or sparingly branched. The stems are light green, terete, and hairy. Alternate compound leaves are widely spreading; they are odd-pinnate with 9-25 leaflets. Individual leaflets are up to 1" long and ¼" across; they are medium green to grayish green, oblong to narrowly elliptic in shape, and smooth along their margins. Upper surfaces of the leaflets are hairless to silky-hairy, while their lower surfaces are pubescent to silky-hairy. Each leaflet has a prominent central vein. The central stalk (rachis) and petiole of each compound leaf is pubescent. At the base of each petiole, there is a pair of small stipules about ¼" long. The stems terminate in short dense racemes about 2-3" long that are covered in buds and bicolored flowers facing all directions. The racemes are held a little above the foliage on short peduncles. Individual flowers are ¾" long and across, consisting of 5 petals, a short tubular calyx with 5 teeth, 10 stamens, and a pistil. Each flower has a typical pea-like floral structure, consisting of an upright banner and a pair of lateral wings that project forward to enclose the keel. The broad banner is white to pale greenish yellow, while the wings are deep rosy pink. The pedicels of the flowers and their calyces are light green and pubescent. The blooming period occurs from early to mid-summer and lasts about 3 weeks. Afterwards, the flowers are replaced by widely spreading seedpods about 1½-3" long. These seedpods are initially light green, but later turn brown; they are silky-hairy. The seedpods are narrowly cylindrical and slightly flattened in shape; each pod contains several seeds that are reniform and somewhat flattened. The root system consists of a deep taproot. Cultivation: The preference is full or partial sun, mesic to dry conditions, and an acidic sandy soil. Goat's Rue adds nitrogen to the soil. Range & Habitat: The native Goat's Rue is occasional in all areas of Illinois, except the east-central section, where it is absent (see Distribution Map). Habitats include upland sand prairies, sandy hill prairies, sand dunes, upland sandy savannas, upland rocky savannas, and sandstone glades. In more wooded areas, Goat's Rue typically occurs where oaks are the dominant trees. Faunal Associations: The nectar and pollen of the flowers attract leaf-cutting bees (Megachile spp., Hoplitis spp.) and possibly other long-tongued bees. The caterpillars of the skipper, Thorybes bathyllus (Southern Cloudywing), feed on the foliage of Goat's Rue and other species in the Bean family. Other insect feeders include caterpillars of the moth Semiothisa eremiata (Three-lined Angle), seed-eating larvae of two straight-snouted weevils (Apion segnipes, Apion perforicolle), the plant bug Teleorhinus tephrosicola, the blister beetle Epicauta murina, and several leaf beetles (Bassareus lituratus, Odontota horni, Odontota notata, Pachybrachis othonus, Phyllecthris gentilis). Among vertebrate animals, the seeds are eaten by the Wild Turkey, while cattle have been observed to browse on the foliage. The roots contain rotenone, which is toxic to insects and fish.
Photographic Location: The photograph of the flowering plant was taken by Keith & Patty Horn (Copyright © 2009) at a prairie in Fayette County, Illinois. The photograph of the plants with mature seedpods was taken by John Hilty at Hooper Branch Savanna Nature Preserve in Iroquois County, Illinois. Comments: Because of its attractive bicolored flowers and widely spreading seedpods, Goat's Rue is fairly easy to identify. If only the foliage is present, then it is possible to confuse this wildflower with Amorpha canescens (Leadplant), Dalea foliosa (Leafy Prairie Clover), and possibly other species in the Bean family. These latter two species have very short seedpods and their flowers are much smaller in size than those of Goat's Rue. Across different populations of Goat's Rue, there is considerable variation in the hairiness of the foliage. Western populations that are found in sunny habitats often have leaflets that are densely covered with silky hairs, while eastern populations that occur in more shaded habitats have leaflets that are less conspicuously hairy.
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Miss Chen
2018年02月24日
Miss Chen
Description: This herbaceous perennial plant is ½–2' tall, producing one or more leafy stems that are erect, ascending, or sprawling. The wiry stems branch sparingly, and they are often curved, arching, or crooked. Young stems are whitish green to silver-colored and terete; they are moderately to densely covered with fine pubescence. Older stems are brown or purple and sparsely to moderately covered with fine pubescence. Alternate leaves occur along the entire length of each stem, becoming slightly smaller in size as they ascend. The leaves are ½–1¼" long and about 4-8 mm. across; they are oblong to elliptic in shape and entire (smooth) along their margins. The bases of leaves are sessile or clasp their stems slightly, while the tips of leaves are short-acute. Both the upper and lower surfaces of leaves are whitish green to silver-colored; they are moderately to densely covered with appressed fine pubescence. The upper stems terminate in one or more flowerheads. On a robust plant, this inflorescence resembles a little-branched open panicle up to ¾' long that has 6-18 flowerheads, otherwise the inflorescence consists of 1-2 short branches with 1-3 flowerheads at their tips or slightly below. The wiry branches of the inflorescence are terete, whitish green to silver-colored, and moderately to densely covered with fine pubescence. Along the branches of larger inflorescences, there are leafy bracts that resemble the alternate leaves. The daisy-like flowerheads are about 1¼" across, consisting of 10-22 ray florets that surround numerous disk florets. The petaloid rays of the flowerheads are linear-oblong in shape, widely spreading, and lavender, deep lavender, or various shades of purple. The tiny corollas of the disk florets are tubular in shape with 5 lanceolate lobes along their upper rims; these lobes are erect to ascending. During the period of bloom, the corollas of the disk florets are white to pale pinkish purple; their anther tubes are yellow and their stigmas are lavender to purple. The blooming period occurs from late summer into autumn, lasting about 1 month for a colony of plants. Afterwards, the florets are replaced by achenes. These achenes are 2-3 mm. long and bullet-shaped with small tufts of hair at their apices; they are dispersed by the wind. The root system is fibrous and occasionally rhizomatous; older plants form short caudices. Occasionally, clonal offsets are produced from rhizomes.
Cultivation: The preference is full sun and mesic to dry conditions. Almost any kind of soil is satisfactory if the site is well-drained, but this plant typically grows in poor soil that is rocky or sandy. A high pH is tolerated. Overall, this plant develops more slowly than most perennial asters (Symphyotrichum spp.) and it is a bit more difficult to grow. It doesn't tolerate much competition from taller ground vegetation. While the drought tolerance of mature plants is good, some of the lower leaves will wither away and fall from the stems. Range & Habitat: The native Silky Aster occurs primarily in the northern tier of counties and in many counties along the Illinois and Mississippi Rivers (see Distribution Map). It is an uncommon plant that appears to be declining in abundance as a result of habitat destruction. These habitats include upland dolomite prairies, gravel prairies, sand prairies, hill prairies, stabilized sand dunes, upland sandy savannas, limestone glades, and prairie remnants along railroads. This is an indicator plant of high quality habitats in dry open areas.
Faunal Associations: The nectar and pollen of the flowerheads attract bumblebees, leaf-cutting bees (Megachile spp.), green metallic bees (Agapostemon spp.), Syrphid flies, and small- to medium-sized butterflies, including the endangered Karner Blue (Lycaeides melissa samuelis); see Reed (1993) and Swengel & Swengel (2000). Syrphid flies are probably non-pollinating. A plant bug, Psallus astericola, feeds on Silky Aster (Knight, 1941). Other insects that feed of the foliage and other parts of asters (Symphyotrichum spp.) include leaf beetles, the larvae of leaf-mining flies, the larvae of gall flies, other plant bugs, aphids, the larvae of moths, the larvae of butterflies, and grasshoppers. Among mammals, the young foliage of these plants are browsed occasionally by rabbits, deer, groundhogs, cattle, horses, and sheep. However, Silky Aster may be an exception to this rule, as it was found to increase in abundance as a result of grazing (Brudvig et al., 2007). Among birds, the Wild Turkey also browses on the foliage of asters; this upland gamebird and the Tree Sparrow also eat their seeds (Martin et al., 1951/1961).
Photographic Location: The photographs were taken at the webmaster's wildflower garden in Urbana, Illinois. Comments: This is a truly beautiful little plant with attractive foliage and flowerheads. It's an excellent candidate as a wildflower in a sunny rock garden. In Illinois, Silky Aster (Symphyotrichum sericeum) can be distinguished from all other asters (Symphyotrichum spp.) within the state by its exceptional foliage, which has a silvery or silky appearance because of the numerous fine hairs covering its stems and leaves. It also has larger flowerheads (often exceeding 1" across) than most native or naturalized species of asters within the state. A scientific synonym of this plant is Aster sericeus.
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Miss Chen
2018年02月23日
Miss Chen
Description: This herbaceous perennial plant is 2-5' tall, branching occasionally. The larger stems are occasionally reddish, and have lines of white hairs. The alternate leaves are up to 5½" long and ¾" across, becoming smaller and narrower as they ascend up the stems. They are lanceolate, narrowly ovate, or linear, and have smooth margins. Underneath, the leaves are whitish green with a reticulate network of fine veins that is quite conspicuous. The inflorescence is large and pyramidal, containing numerous daisy-like composite flowers from ½–¾" across. Each flower has 20-30 lavender or light blue ray florets surrounding numerous yellow disk florets that eventually become reddish purple. The blooming period occurs from early to mid-fall, and lasts about a month. There is no noticeable floral scent. The achenes develop with small tufts of hair, and are dispersed by the wind. The root system is fibrous and rhizomatous. The Willow Aster often spreads vegetatively to form small to large colonies. Cultivation: The preference is full sun, moist conditions, and fertile loamy soil. Foliar disease occurs occasionally, which may involve some yellowing of the leaves and the formation of black spots. This affects primarily the older leaves near the base of the plant, otherwise the foliage remains attractive. Some standing water is tolerated if it is temporary.
Range & Habitat: The native Willow Aster is widely distributed, and it occurs in most counties of Illinois (see Distribution Map). This plant is occasional to locally common. Habitats include moist black soil prairies, moist meadows along rivers and lakes, thickets, roadside ditches, abandoned fields, and other poorly drained areas. Faunal Associations: Many kinds of insects visit the flowers, including long-tongued bees, short-tongued bees, flies, butterflies, and skippers. Among the bees, this includes such visitors as honeybees, bumblebees, Halictine bees, and some Andrenid bees that fly late in the season. Some Syrphid flies and beetles may feed on the pollen, otherwise these insects seek nectar; bees also collect pollen for their larvae. The caterpillars of the butterflies Chlosyne nycteis (Silvery Checkerspot) Phyciodes tharos (Pearl Crescent) feed on the foliage, as well as the caterpillars of several species of moths (see Moth Table). Various insects suck the juices from this and other asters, including plant bugs, lace bugs, and aphids. The Wild Turkey eats the foliage and seeds to a limited extent. Deer browse on this plant occasionally, while rabbits nibble on the foliage of immature plants.
Photographic Location: The photographs were taken at Loda Cemetery Prairie in Iroquois County, Illinois. Comments: This is another attractive aster for autumn bloom, producing abundant flowers. The Willow Aster can be distinguished from other asters (Symphyotrichum spp.) by the conspicuous reticulated pattern on the lower surface of its leaves. In addition, the stalks of the flowerheads are relatively short and they are covered with relatively large leafy bracts. Unlike many woodland asters, the leaves of Willow Aster are always narrow and willow-like, even at the base of the plant, and they lack serrated edges. The flowers are usually lavender or light violet, although sometimes they are white.
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Miss Chen
2018年02月23日
Miss Chen
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.
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Miss Chen
2018年02月23日
Miss Chen
Description: This perennial plant is 1-2' tall, branching frequently to create a bushy appearance. The slender stems are rather stiff and slightly pubescent; the lower stems turn brown and become slightly woody during the fall. The alternate leaves are up to 2" long and ½" across, becoming smaller as they ascend the stems; they are typically one-half the maximum size or a little less. They are linear to linear-oblong, slightly pubescent, and smooth along the slightly ciliate margins. These leaves are rather densely crowded along the stems (particularly the upper stems) and sessile. The compound flowers are daisy-like and about 1–1¼" across. Each compound flower consists of about 20-35 blue-violet or purple ray florets that surround numerous disk florets that are yellow or amber. These disk florets later become reddish purple. Each compound flower is subtended by spreading linear bracts that resemble the upper leaves. The blooming period occurs during the fall and lasts about 1-2 months; a robust plant will be covered with flowerheads. There is no noticeable floral scent, although the crushed foliage and flowerheads have a balsam-like aroma. Aromatic Aster is one of the last wildflowers to bloom prior to heavy frost. The achenes have small tufts of light brown hair and are distributed by the wind. The root system is fibrous and rhizomatous; older plants often have a short caudex. There can be significant variability in the characteristics of plants across different locations. Cultivation: The preference is full sun and dry conditions, although an average moisture level is tolerated if the site is well-drained. Poor, rocky soil with open terrain is preferred; a high pH is tolerated. Some of the lower leaves may wither away before the plants begin to bloom, but the foliage usually remains quite attractive. At moist fertile sites, this plant has trouble competing against tall aggressive plants, unless such neighbors are selectively weeded out.
Range & Habitat: The native Aromatic Aster occurs primarily in northern Illinois, the hilly sections of southern Illinois, and in areas bordering the Mississippi and Illinois rivers (see Distribution Map). It is generally an uncommon plant, although locally common at a few exceptional sites. Habitats include mesic to dry gravel prairies, dolomite prairies, gravelly hill prairies, limestone glades, and rocky bluffs along major rivers. Faunal Associations: Many insects visit the flowers, including long-tongued bees, short-tongued bees, small to medium-sized butterflies, and skippers. These insects seek nectar primarily, although the bees also collect pollen. Many kinds of insects feed on the foliage and other parts of asters, including the caterpillars of the butterfly Chlosyne nycteis (Silvery Checkerspot) and many moth species (see Moth Table). The Wild Turkey and possibly other upland gamebirds eat the seeds and foliage to a limited extent. Mammalian herbivores occasionally eat the foliage of asters, even though their food value is low.
Photographic Location: The above photographs were taken in the wildflower garden of the webmaster in Urbana, Illinois. Comments: This aster has attractive flowers and is fairly easy to cultivate in a sunny rock garden and similar areas. Aromatic Aster can be distinguished from other asters (Symphyotrichum spp.) by the number of ray florets per flowerhead (greater than 20), the size of its flowerheads (usually about 1" across or slightly more), and the spreading linear bracts underneath each flowerhead. The leaves are shorter and more narrow than those of many other Aster spp., and they release a pleasant aroma when crushed. In general habit, Aromatic Aster has denser foliage and a bushier habit than other asters, which are usually more tall and lanky. In mass-market horticulture, some plants that are labeled 'Aromatic Aster' appear to be hybrids of Aromatic Aster and Symphyotrichum novae-angliae (New England Aster). These cultivated plants tend to be larger in size and have larger lower leaves; their flowerheads are slightly larger and more double than those of Aromatic Aster.
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Miss Chen
2018年02月23日
Miss Chen
Description: This herbaceous perennial plant is up to 4' tall, consisting of a central stem that branches occasionally near the top. The central stem and side branches are covered with short white hairs. The alternate leaves are up to 4" long and 1" wide, becoming smaller as they ascend the flowering stems. They are lanceolate or oblong, pubescent, and clasp the stem at the base of each leaf. Their margins are smooth, but ciliate. Clusters of composite flowers occur at the ends of the upper stems. Each composite flower consists of numerous gold or yellow disk florets, which are surrounded by 30 or more ray florets that are purple, lavender, or light pink. Each composite flower is about 1½" across. A mature plant may bear two dozen or more of such flowers, putting forth a showy display. There is no noticeable floral scent. The blooming period occurs from late summer to fall, and lasts about 2 months. The root system consists of a stout caudex with fibrous roots, which often produces short thick rhizomes, enabling this plant to spread vegetatively. The achenes are longitudinally ribbed and slightly hairy, with tufts of hair that enable them to be carried off in the wind. Cultivation: The preference is full or partial sun, and moist to average conditions. The soil can contain loam or clay. This plant can become stressed out by hot dry weather, often dropping its lower leaves in response, while the remaining leaves may turn yellow or brown. Another problem is that the stems often flop over in the absence of supportive vegetation. Powdery mildew often afflicts the leaves during the cool, moist weather of the fall. This is an easy plant to grow in moist conditions, but it is more difficult to maintain in good condition throughout the year. Sometimes it becomes aggressive and spreads vegetatively.
Range & Habitat: The native New England Aster occurs throughout Illinois, except in a few southern counties (see Distribution Map). It is a common plant. Habitats include moist to mesic black soil prairies, clay prairies, thickets, moist meadows in woodlands, open areas along rivers and lakes, fens, abandoned fields, open areas along railroads and roadsides, and miscellaneous waste areas. Some populations are probably escapes from cultivated plants. This plant colonizes disturbed areas readily, but it also occurs in high quality habitats. Faunal Associations: The flowers are visited primarily by long-tongued bees, bee flies, butterflies, and skippers. Short-tongued bees and Syrphid flies also visit the flowers, but they collect pollen primarily and are non-pollinating. Among the long-tongued bees, are such visitors as bumblebees, honeybees, Miner bees, and large Leaf-Cutting bees. Cross-pollination by these insects is essential, otherwise the seeds will be infertile. The caterpillars of many moths feed on various parts of this and other asters (see Moth Table). Other insects feeding on this plant include Lygus lineolaris (Tarnished Plant Bug), Poccilocapsus lineatus (Four-Lined Plant Bug), Corythuche marmorata (Chrysanthemum Lace Bug), and Macrosiphum euphoriaca (Potato Aphid). The seeds and leaves of this plant are eatened to a limited extent by the Wild Turkey, while deer, livestock, and rabbits occasionally browse on the foliage, sometimes eating the entire plant. However, New England Aster isn't a preferred food source for these animals.
Photographic Location: The photographs were taken at Judge Webber Park in Urbana, Illinois. Comments: New England Aster can be variable in terms of its size, color of the flowers, and other characteristics. This plant has attractive flowers with a long blooming period, but it often appears messy by the fall as a result of drought, insects, and disease. It is easy to distinguish this aster from other asters (Symphyotrichum spp.), because its compound flowers are larger in size and they have more numerous ray florets.
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Miss Chen
2018年02月23日
Miss Chen
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.
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Miss Chen
2018年02月22日
Miss Chen
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.
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Miss Chen
2018年02月22日
Miss Chen
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.
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Miss Chen
2018年02月22日
Miss Chen
Description: This herbaceous vine is a summer annual about 2-6' long that branches occasionally. Its slender stems can climb by twining about adjacent vegetation; they are finely pubescent. Alternate trifoliate leaves occur at intervals along the stems. Each leaflet is about 1" long and 1/3" (8 mm.) across; it is oblong-lanceolate, smooth along the margins, and finely pubescent on both the upper and lower sides. Each trifoliate leaf has a long petiole about 1-2" long that is also finely pubescent; there is a pair of small lanceolate bracts at the base of each petiole. No tendrils are produced by this vine. At the base of the middle to upper leaves, a slender flowering stalk (peduncle) about 1-4" long is occasionally produced. Each stalk terminates in a dense cluster of 1-6 small flowers; usually only one flower in a cluster is in bloom at a time. Each flower is up to ¼" long; it has a pale pink to purplish pink corolla. This corolla has a typical pea-like structure that consists of a standard, keel, and enclosing wings. However, the narrow keel and its wings are somewhat unusual in that they curve upward in front of the standard, instead of remaining straight. This characteristic distinguishes the Strophostyles genus from many other members of the Bean family. The short tubular calyx of each flower is light green to purple and finely pubescent; it has 4-5 shallow teeth along its rim and a pair of small bracts (bracteoles) at its base. The pedicel of each flower is very short. The blooming period occurs from late summer into the fall and lasts about 1-2 months. Each flower is short-lived and lacks any noticeable floral scent. A fertile flower is replaced by a cylindrical seedpod about 1–1½" long that has a beaked outer tip. This seedpod is initially green, but becomes dark brown with maturity; it is finely pubescent to conspicuously hairy. Each seedpod contains a few large seeds that are oblongoid in shape; they become dark, shiny, and hairless with maturity. The root system consists of a taproot. This vine spreads by reseeding itself. Cultivation: The preference is full or partial sun, mesic to dry conditions, and sandy soil. Conventional garden soil containing loam or clay-loam is tolerated if there is not too much competition from taller plants. The seeds may remain in the ground for several years before they germinate; scarification of the seeds can speed up this process. The roots add nitrogen to the soil by forming a symbiotic association with rhizobial bacteria. Range & Habitat: The native Small Fuzzy Bean occurs occasionally in southern Illinois and in sandy areas of central and northern Illinois, otherwise it is uncommon or absent (see Distribution Map). Habitats include open rocky woodlands, open sandy woodlands, sandy savannas, glades, thickets, sand prairies, and sandy fields. This species is usually found in rather dry areas with sparse ground vegetation. Occasional wildfires are probably beneficial in removing competition from woody vegetation and other tall plants.
Faunal Associations: The nectar of the flowers occasionally attracts bees, including bumblebees, Leaf-Cutting bees (Megachile spp.), and Dagger bees (Calliopsis spp.). The extra-floral nectaries attract ants and Halictid bees. The caterpillars of the following skippers occasionally feed on the foliage of Strophostyles spp. (Fuzzy Beans): Epargyreus clarus (Silver-Spotted Skipper), Thorybes bathyllus (Southern Cloudywing), and Urbanus proteus (Long-tailed Skipper). Some leaf beetles feed on the foliage as well, including Cerotoma trifurcata (Bean Leaf Beetle), Sumitrosis ancoroides, and Sumitrosis pallescens; the larvae of the latter two species are leaf-miners. The Mourning Dove and Bobwhite Quail eat the seeds of Fuzzy Beans, while the foliage is readily eaten by cattle, deer, and other mammalian herbivores. Photographic Location: The wildflower garden of the webmaster in Urbana, Illinois. The dainty foliage of Aster oblongifolius (Aromatic Aster) can be observed in the background of the photographed trifoliate leaf.
Comments: This rather ordinary-looking vine has small flowers that are short-lived. Other common names for this species are Small Wild Bean and Small Woolly Bean. Two other vines in this genus that occur in Illinois are the following: Strophostyles helvola (Large Fuzzy Bean) and Strophostyles umbellata (Perennial Fuzzy Bean). As the common name implies, Large Fuzzy Bean is a more robust vine with longer stems and larger leaves; the leaves of this species are sometimes lobed. It is also a summer annual, but prefers more moist habitats. Similarly, the Perennial Fuzzy Bean is more robust with longer stems and larger leaves; this perennial vine is restricted to southern Illinois. These latter two species have slightly larger flowers (greater than ¼" in length) than the Small Fuzzy Bean (up to ¼" in length); they all have keels on their flowers that curve upward and their seedpods are finely pubescent to conspicuously hairy. While the mature seeds of Small Fuzzy Bean are shiny and hairless, the mature seeds of Large Fuzzy Bean and Perennial Fuzzy Bean are usually mealy-pubescent.
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