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Miss Chen
2018年02月08日
Miss Chen
Description: This herbaceous perennial wildflower is 2-5' tall with an erect central stem that is unbranched. This stem is light green, terete, stout, and covered with short stiff hairs; it often becomes brown with age. The alternate leaves are up to 4½" and 2" across, becoming gradually smaller as they ascend the stem. They are lanceolate to broadly lanceolate, elliptic, orClose-up of Flowerhead oblanceolate in shape, medium green, and covered with short stiff hairs on their undersides. The margins of the lower leaves are dentate, while the margins of the upper leaves are more smooth. Most of the leaves are sessile, although some of the lower leaves may clasp the stem slightly; some of these leaves may wither before the blooming period. The foliage contains a bitter white latex. The central stem terminates in a spike-like raceme (or something similar to this) about ½–2' long. Along the central stalk of this raceme, are small clusters of flowerheads; small clusters of flowerheads also develop from the axils of the upper leaves. Each flowerhead is about ½–1" across, consisting of 10-18 ray florets and no disk florets. Each of these ray florets is white or cream-colored, linear-oblong in shape, and truncate at its tip with 5 small teeth. The base of each flowerhead is about ½" long and cylindrical in shape; it is covered with 8-10 phyllaries (floral bracts) that are light green, conspicuously hairy, and linear-oblong in shape. At the bottom of the flowerhead's base, there are several secondary phyllaries that are much smaller in size and insignificant. The reproductive organs of the ray florets consist of divided styles with strongly recurved tips and elongated stamens. The blooming period occurs from late summer to early fall and lasts about 2-3 weeks. Each fertile floret is replaced by an oblongoid achene with a small tuft of hairs. These hairs are straw-colored or light brown. Distribution of the achenes is provided by the wind. The root system consists of a stout taproot that is broadest toward the middle. This plant reproduces by reseeding itself. Cultivation: The preference is full sun and mesic to dry conditions. Different kinds of soil are tolerated, including those that are loamy, rocky, or sandy. It is difficult to establish this plant from seed as it is slow-growing and the young seedlings are vulnerable to "damping off" and other problems. Range & Habitat: Rough White Lettuce exists in widely scattered populations throughout Illinois (see Distribution Map), where it is native. Populations of this species have declined and it has become rather uncommon, largely because of the destruction of prairie habitat throughout the state. Habitats include black soil prairies, sand prairies, savannas, rocky upland woodlands, limestone glades, and prairie remnants along railroads. At one time, Rough White Lettuce was considered a weed in pastures, but this is no longer the case. Today, this conservative species is typically found in high quality prairies. Because of the difficulty in propagating this species, it is not often used in prairie restorations. Faunal Associations: There is a paucity of records about floral-faunal relationships for this species. Bumblebees visit the flowerheads for nectar. Cattle and other mammalian herbivores usually leave this plant alone because of its rough hairy foliage and bitter latex (see Ada Georgia, A Manual of Weeds, 1913).
Photographic Location: The photograph of the flowerhead was taken by Pat Chapel (Copyright © 2006) at the Prospect Cemetery Prairie in Ford County, Illinois, while the photograph of the stem and leaves was taken by the webmaster at Loda Cemetery Prairie in Iroquois County of the same state. Comments: This is a true prairie plant that blooms during the fall. It is somewhat similar in appearance to Prenanthes racemosa (Glaucous White Lettuce), which prefers moist habitats. This latter species has a central stem that is glabrous and glaucous throughout, while the central stem of Rough White Lettuce has stiff short hairs. The color of the flowerheads is also somewhat different: the flowerheads of Glaucous White Lettuce often have a pale purple tint, while those of Rough White Lettuce are cream-colored or white. Other Prenanthes spp. in Illinois are normally found in woodlands, rather than prairies. In contrast to Rough White Lettuce, these woodland species have nodding flowerheads, widely spreading inflorescences, and leaves that are often deeply lobed.
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Miss Chen
2018年02月08日
Miss Chen
Description: This perennial plant sprawls along the ground by means of stolons; it is less than 1' tall. The slender stems and stolons are initially green, but become red with age. Depending on the local ecotype, they can be nearly glabrous, or covered with spreading white hairs. The stolons can extend up to 3' and their tips often root in the ground, forming new plantlets. The compound leaves are palmate (with 5 leaflets) and alternate along the stolons or stems. Each leaflet is up to 3" long and ¾" across. There is coarse serration along the margins, except near the base, and prominent venation. The upper surface is glabrous, while the lower surface may be hairy or nearly glabrous. The leaflets are narrowly ovate (but with blunt tips), obovate, or oblanceolate; young leaflets often have their margins curled upward. A single yellow flower develops from a long pedicel from the upper axils of some of the compound leaves. This flower is about ½" across, and has 5 yellow petals that are narrow at the base, but rounded toward their tips, which are sometimes notched. The green calyx has 5 triangular tips that are a little shorter than the petals. The center of the flower has a somewhat flattened reproductive structure, which is surrounded by about 20 stamens. The blooming period can occur from spring to mid-summer, and lasts about a month. Only a few flowers are in bloom at the same time. There is no noticeable floral scent. The achenes are without tufts of hair. There is a short, thick rootstock that divides into coarse secondary roots. This plant often forms loose colonies by means of its stolons.
Cultivation: The preference is partial to full sun, and moist to dry conditions. The soil can consist of loam, clay-loam, or contain gravelly material. This is an easy plant to grow that presents few problems. Range & Habitat: The native Common Cinquefoil occurs in every county of Illinois and it is fairly common (see Distribution Map). Habitats include mesic to dry black soil prairies, open upland forests, savannas, gravelly seeps, and abandoned fields. This plant occurs in both disturbed areas and high quality habitats. In tallgrass prairies, it is one of the understory plants. Faunal Associations: The flowers primarily attract small bees and flies, including Mason bees, Small Carpenter bees, Nomadine Cuckoo bees, Halictid bees, Syrphid flies, Tachinid flies, Blow flies, and others. Less common visitors are wasps, skippers, and butterflies. These insects seek nectar, although bees also collect pollen. The seeds are little used by birds. Small mammalian herbivores, such as rabbits and groundhogs, often eat the foliage. It is possible that some of the seeds of Common Cinquefoil can pass through their digestive tracts unharmed, and are thus distributed by them; some studies involving livestock have found this to be the case with a similar species, Potentilla recta (Sulfur Cinquefoil). Photographic Location: The above photographs were taken at Loda Cemetery Prairie in Iroquois County, Illinois. Comments: This is another plant that fits the stereotype of a weed, but it also occurs in prairies and other native habitats. The flowers are reasonably showy during the spring, but few in number. Common Cinquefoil resembles many other species of Cinquefoil, both native and introduced. Its compound leaves almost always have 5 leaflets, the flowers are bright yellow, and it sprawls along the ground; other species often have a fewer or greater number of leaflets, their flowers may be white or pale yellow, or they are erect. Common Cinquefoil is perhaps most similar to the native Potentilla canadensis (Dwarf Cinquefoil), except that the latter is a smaller plant with blunter leaftlets that are strongly obovate or oblanceolate.
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Miss Chen
2018年02月07日
Miss Chen
Description: This plant is a biennial or short-lived perennial that persists as a low rosette of basal leaves for 2-4 years. The blades of these basal leaves are up to 6" long and 5" across; they are bipinnate-pinnatifid or pinnate-pinnatifid in structure and triangular in outline. Individual leaflets (or subleaflets) are moderately to deeply divided into pinnate lobes; these lobes usually have a few coarse teeth along their margins. The surface of basal blades is medium green and glabrous (or nearly so). The petioles of the basal leaves are up to 4" long and they are covered with short fine pubescence to a greater or lesser extent. In addition, the leaflets of the basal leaves have conspicuous petiolules (basal stalklets). The petiolules of the terminal leaflets are longer than those of the lateral leaflets. Eventually, this plant bolts to produce a single flowering stalk with a few alternate leaves. This stalk is light green to pale brownish red, terete (round in cross-section), somewhat stout, and 1½-3' tall. It is unbranched, except toward the apex, where the umbels of flowers occur, and usually it is covered with short fine pubescence to a greater or less extent. The alternate leaves are up to 3" long and 3" across, pinnate-pinnatifid in structure, triangular in outline, and sessile; they become smaller in size as they ascend the stem. Similar to the basal leaves, the leaflets of alternate leaves are moderately to deeply divided into pinnate lobes; these lobes usually have a few coarse teeth along their margins. The surface of alternate leaves is medium green and glabrous (or nearly so). The central stalk terminates in a few compound umbels of flowers that span 1½-3" across. In addition, lateral compound umbels of flowers often develop from the axils of upper leaves on peduncles 2" long or more. Depending on their stage of development, the tops of these umbels areDistribution Map dome-shaped to nearly flat. A typical umbel will have about 10-15 congested umbellets, and each umbellet will have 10-15 flowers. The rays (stalklets) of both the umbels and umbellets are light green, angular, and more or less covered with short fine pubescence. Both umbels and umbellets lack significant floral bracts. When such bracts are present, they are small in size, linear in shape, and soon wither away. Each flower has 5 yellow petals with incurved tips, a light green or yellowish green calyx with 5 minute ovate teeth, 5 stamens, and a pistil. Individual flowers are about 1/8" (3 mm.) across. The blooming period occurs from mid-spring to early summer for about 1 month. Each flower is replaced by a dry fruit (schizocarp) that becomes 6-9 mm. long at maturity. Immature fruits are green, but they later become yellow, and finally brown. Each fruit consists of a pair of seeds that develop winged margins at maturity. These seeds are distributed to some extent by the wind. The root system consists of a deep taproot. Cultivation: The preference is full sun, mesic to dry conditions, and soil containing loam, rocky material, or sand. The seeds can be difficult to germinate, requiring a winter dormancy of about 120 days, and each plant is rather slow to develop after germination has occurred. Range & Habitat: The native Prairie Parsley occurs in scattered areas of northern, southern, and west-central Illinois, where it is fairly uncommon. Populations of this plant within the state appear to be declining. Illinois lies along the NE range limit of this plant. Habitats include upland prairies, hill prairies, limestone glades, chert glades, thinly wooded bluffs, and savannas. Prairie Parsley is an indicator plant of original prairie. It is rarely found in disturbed areas. This conservative species may require occasional wildfires to remove excess brush and debris, and to facilitate germination of the seeds. Faunal Associations: The tiny flowers attract primarily small bees, miscellaneous flies, and occasional wasps (Robertson, 1929). Prairie Parsley is one of the species in the Carrot family that the oligolectic bee, Andrena ziziae, visits for pollen and nectar. The caterpillars of a butterfly, Papilio polyxenes asterius (Black Swallowtail), feed on the foliage of this plant. Cattle and other mammalian herbivores browse readily on the non-toxic foliage.
Photographic Location: The wildflower garden of the webmaster in Urbana, Illinois. Comments: Most people might regard Prairie Parsley as another weed, but it is a conservative native plant with high fidelity to prairies. This plant is perhaps at its most attractive when its fruits have reached the showy yellow stage. The native Prairie Parsley in Illinois should not be confused with either Wild Parsnip (Pastinaca sativa) or Golden Alexanders (Zizia aurea). Like Prairie Parsley, Wild Parsnip and Golden Alexanders have compound umbels of small yellow flowers, but they differ by having simple-pinnate leaves with leaflets that are less lobed. Another species, Flat-Leaved Parsley (Petroselinum crispum neapolitanum), has compound leaves and compound umbels of flowers that are very similar to those of Prairie Parsley, but Flat-Leaved Parsley differs by having mature seeds that lack winged margins.
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Miss Chen
2018年02月07日
Miss Chen
Description: This annual plant is usually unbranched and 4-12" tall. The central stem is sharply angular and hairless. The alternate or opposite leaves are sessile against the stem, ranging up to 1½" in length and 1/6" (4 mm.) across. They have a prominent mid-vein, smooth margins, and are linear or oblong-linear in shape. The central stem terminates in a spike-like raceme of flowers. This raceme is about 1" long and ½" across. The flowers are variable in color, ranging from purplish pink, white, or green. An individual flower consists of two large sepals (i.e., the wings), three small sepals that are barely perceptible, and three small petals that form a narrow tube. One of these petals has a small crest at its tip. The wings are about 1/3" (8 mm.) long and ovate – they are the most prominent part of the flower and determine its color. The tiny tube of the petals has a similar color, but is short-lived, typically occurring near the apex of the inflorescence amid the wings. The stalk beneath the raceme has an irregular surface and spike-like remnants of the bracts where the older flowers occurred. The blooming period is from mid-summer to early fall, and lasts about 1-2 months for a colony of plants. Each flower is replaced by a capsule containing two seeds that are hairy. The root system consists of a slender taproot that has a wintergreen fragrance. This plant spreads by reseeding itself. Cultivation: The preference is full or partial sun and moist to dry conditions. Poor soil is preferred, as this reduces competition from other plant species. This plant often grows in soil that sandy or rocky, but will thrive in loamy soil as well if it receives adequate sunlight. Range & Distribution: The native Field Milkwort occurs occasionally in most counties of Illinois. It is the most common Polygala spp. (Milkwort species) in the state. Habitats include moist to dry prairies, sand prairies, typical savannas and sandy savannas, woodland edges, glades, and abandoned fields. Faunal Associations: The nectar of the flowers attracts small to medium-sized long-tongued bees, short-tongue bees, and bee flies. Among the bees, are such visitors as Dagger bees, Miner bees, and Cuckoo bees. Little information is available about the food value of the Milkworts to birds and animals. Photographic Location: A moist sand prairie at Hooper Branch Savanna Nature Preserve in Iroquois County, Illinois. The location was flooded earlier in the year, which is why the leaves have a muddy appearance. Comments: As a group, the Milkworts have not received as much attention as they deserve. Some species, such as this one, have fairly attractive flowers. They are usually found in locations with acid sandy soil, but some species prefer dry sites with rocky material or loess. The Polygala spp. can be distinguished from each other by taking into consideration the following: 1) whether the leaves are alternate or whorled, 2) the shape, size, and color of the wings on the flowers, 3) the density of flowers on the spike or spike-like raceme, and 4) the conspicuousness of the tubular petals. The slender leaves of Field Milkwort are usually alternate, rather than whorled. This species has fairly large wings (about 1/3" or 8 mm.) that are ovate in shape. They are often purplish pink, but may turn white near the base. The density of flowers on the spike-like raceme is high, while the tubular petals are inconspicuous. Field Milkwort has a wide distribution in the Eastern United States, and different varieties have been described.
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Miss Chen
2018年02月07日
Miss Chen
Description: This annual plant is 4-12" tall and usually unbranched. The central stem is angular and hairless. The leaves occur in whorls of 4 and are sessile against the stem. They are up to 1½" long and 1/3" (8 mm.) across, linear or linear-oblong in shape, with smooth margins. The central stem terminates in a dense spike of flowers up to 2-3" long and 1" across. These flowers are variable in color, ranging from purplish pink or pink to greenish white. Each flower is about 1/3" (8 mm.) across, consisting of 2 large sepals (called 'wings'), 3 tiny sepals, and 3 petals that form a narrow tube with a crest at its apex. The wings are the most conspicuous part of the flower and determine its color. They are broadly triangular (or deltoid) in shape, and lie to the right and left of the tubular petals. These wings persist on the spike long after the petals have fallen off, and have the appearance of sharp-pointed bracts. The narrow tubular petals are observable near the apex of the spike. They are usually some shade of pink, but quickly fade to brownish yellow, before falling off the spike. The blooming period occurs from mid-summer to early fall, and lasts about 1-2 months. When fertilization occurs, each flower is replaced by a 2-seeded capsule. The seeds are hairy. The root system consists of a taproot. This plant spreads by reseeding itself. Cultivation: The preference is full or partial sun, and moist sandy soil. The pH should be somewhat acid. This plant can withstand occasional flooding if it is temporary. Range & Habitat: Cross-Leaved Milkwort occurs primarily in NE Illinois (see Distribution Map). It is an uncommon plant and native to Illinois. Habitats include moist sand prairies, shrub prairies, sandy Black Oak savannas, and edges of sandy marshes. It also occurs along paths in these areas, preferring the reduced competition from taller plants. Faunal Associations: Probably small to medium-sized long-tongued and short-tongued bees visit the flowers for nectar. Little information is available about this plant's value as a food source to birds or mammals. Photographic Location: Along a path in the Hooper Branch Savanna Nature Preserve in Iroquois County, Illinois, where Cross-Leaved Milkwort occurred in a moist sand prairie that was somewhat shrubby and sunny moist areas of Black Oak Savanna. This area was prone to occasional flooding from heavy rains. Comments: The thick spike of flowers of this odd little plant is very conspicuous and easy to spot. Cross-Leaved Milkwort is relatively easy to identify because of the bract-like wings that spread horizontally (left and right) from the center of each flower. In other species of Milkwort, these wings are held upright and resemble petals. The whorled leaves are another distinctive feature, as many species of Milkwort have alternate leaves. Another common name for this plant is 'Drumheads,' which refers to the shape of the stout spike of flowers. Different varieties of Cross-Leaved Milkwort have been described, but only Polygala cruciata aquilonia is known to occur in Illinois.
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Miss Chen
2018年02月07日
Miss Chen
Description: This annual plant is about 2' tall and largely unbranched, except near the base. The major stems are stout, round, and covered with rather long glandular hairs, especially where new growth occurs. The lower and middle compound leaves along the stems are trifoliate with long petioles. The individual leaflets are about 1½" long and ½" across. They are oval, ovate, or oblong, and have smooth margins that are slightly ciliate. Their surface is dull green and covered with short fuzzy hairs, with longer hairs occurring along the lower central vein. When the foliage is bruised or rubbed against, a fetid odor is emitted. Smaller leaves on short petioles occur along the upper stems that are simple, rather than compound. The major stems terminate in racemes of flowers of variable length – these flowers are whorled near the apex of the stems with scattered seedpods below. Each flower is about 1" across and has an unusual structure. There are 4 white petals about ½" long that are heart-shaped, but with a long narrow base. About 8-12 strongly exerted stamens are reddish purple and rather unequal in length, with the upper stamens about twice the length of the petals. The single slender style is much shorter than the stamens and less conspicuous. At the base of each flower, is a gland that secretes a conspicuous drop of bright red fluid. The calyx is divided into 4 triangular sepals that are reddish purple. The flowers occur on long hairy pedicels. The blooming period occurs from summer until the fall, and can last several months. There is no obvious floral scent. Pollinated flowers develop sizeable seedpods up to 3" long that are sessile against the pedicels (i.e., there is no stipular growth at the base of the seedpods). These seedpods resemble stout bean pods that can divide into two halves. Each seedpod has fuzzy hairs on the outer surface, and forms a long terminal spike that withers away as the seedpod matures. Mature seedpods are held more or less erect, rather than drooping downward from the stems. The individual seeds have an irregular patterned surface. The root system consists of a long taproot without rhizomes. This plant spreads by reseeding itself. Cultivation: It is best to growth this plant in full sunlight, mesic to dry conditions, and soil that is rocky or sandy. The base of the central stem of this plant may sprawl along the ground if it is grown in moist, fertile soil. Foliar disease and insect pests are not generally troublesome.
Range & Habitat: Large-Flowered Clammyweed is an uncommon plant that occurs in widely scattered counties in Illinois (see Distribution Map), where it is probably native. This plant is more common in areas that lie to the west of Illinois. Within the state, it has been found in such natural habitats as openings in bluffs, glades, or hill prairies, and may occur occasionally as an adventive plant along railroads. Because of the ornamental flowers, this plant can be found in flower gardens, but this is uncommon. Faunal Associations: Various bees visit the flowers for nectar, while flower flies feed on the pollen from the exerted anthers. However, the latter group of insects does not effectively pollinate the flowers. The foliage is not known to be toxic to mammalian herbivores, notwithstanding the fetid odor, but little appears to be known about the attractiveness of the foliage as a food source. Similarly, little is known about the attractiveness of the seeds to small rodents or upland gamebirds. Because the seeds of similar kinds of plants, such as the Cleome spp. (Bee Plants) in the western states, are occasionally eaten by the Ring-Necked Pheasant, Mourning Dove, and various small rodents, it is possible that the same or similar species also eat the seeds of Polanisia spp. (Clammyweeds).
Photographic Location: The edge of vegetable garden in Meadowbrook Park, Urbana, Illinois. The plant was blooming during early September. Comments: Large-Flowered Clammyweed is primarily a western species, and Illinois lies on the eastern edge of its distribution. It is fairly attractive while in bloom and has some resemblance to Cleome hassleriana (Spider Flower) of mass-market horticulture. This latter species is a larger plant from South America with palmate compound leaves. The more typical variety of Clammyweed, Polanisia dodecandra dodecandra, has smaller flowers with petals about ¼" and stamens that are barely longer than the petals. It less showy than the variety of Clammyweed that is described here, and it has a more eastern distribution. An uncommon species of Clammyweed, Polanisia jamesii (James' Clammyweed), is a sand prairie species that has narrow leaflets and flower petals with irregular fringed edges. What distinguishes the Polanisia spp. (Clammyweeds) from the Cleome spp. (Bee Plants) is the lack of a stipe connecting the seedpod with the pedicel. This stipe of the Bee Plants is a stalk-like extension of the developing seedpod. Both groups of plants are members of the Caper family.
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Miss Chen
2018年02月07日
Miss Chen
Description: This plant is a summer annual that branches sparingly to occasionally; it is ¾–2' tall. The stems are light green or light reddish green, terete, finely short-pubescent, and sparsely to abundantly hairy. The leaves are opposite or alternate; they occur sparingly along the stems, except at their apices, where they occur in dense pseudo-whorls. The leaves are ¾–3" long and ¼-1" across; they are at least twice as long as they are across. Depending on the variety, the leaves are variably shaped; var. dentata has leaves that are elliptic-lanceolate to ovate, while var. cuphosperma has leaves that are linear-lanceolate to elliptic. The leaf margins are coarsely dentate. The leaf bases are wedge-shaped, while their tips are bluntly acute to acute. The upper leaf surfaces are medium to dark green and glabrous, while the lower leaf surfaces are light-medium to medium green and glabrous to short-pubescent along the lower sides of the veins. The petioles are 3-20 mm. (1/8–3/4") long, light green, glabrous to short-pubescent, and narrowly winged toward the leaf bases. The foliage of this plant exudes a white milky sap when it becomes damaged. The stems terminate in flat-topped clusters of flowers spanning about ¾–2" across. Each cluster of flowers has several cyathia with a mixture of flowers and immature fruits; the cyathia and fruits are light green and glabrous, although sometimes the fruits become light red or purple in response to strong sunlight. A cyathium is a small cup-like structure spanning about 3 mm. (1/8") across that contains a single pistillate (female) flower and several surrounding staminate (male) flowers. These flowers are devoid of petals and sepals; their tiny reproductive organs are yellow, light pink, or white. Underneath the clusters of flowers, there are small leafy bracts up to ¾" long and ¼" across; they are few in number and linear-elliptic to elliptic in shape. The blooming period occurs from mid-summer to autumn, lasting about 1 month for a colony of plants. There is no noticeable floral scent. After blooming, the pistillate flowers are replaced with 3-lobed nodding fruits that span about 4-5 mm. across. These fruits are subgloboid (globoid and slightly flattened) in shape, and they are exserted from their cyathia on short curved stalks.
Each fruit contains 3 seeds. Individual seeds are 2–2.5 mm. long and slightly less across, ovoid-globoid in shape, gray to nearly black, minutely bumpy across the surface, and grooved along one side. The root system consists of a taproot. Cultivation: The preference is full sun, mesic to dry conditions, and poor soil containing significant amounts of clay, sand, or gravel. Disease rarely bothers the leaves and drought resistance is excellent. The seeds germinate after the weather becomes warm. Range & Habitat: The native Toothed Spurge occurs in almost all counties of Illinois (see Distribution Map), where it is occasional to locally common. Habitats include disturbed areas of upland prairies (including gravel and sand prairies), hill prairies, open upland thickets, limestone glades, abandoned fields, areas along cultivated fields, areas along railroads, areas along parking lots, roadsides, and open waste ground. Among these various habitats, Toothed Spurge is perhaps most common along railroads. This plant favors open disturbed areas.
Faunal Associations: The flowers are probably visited by small bees, Syrphid flies, and wasps; both nectar and pollen are available as floral rewards. A flea beetle, Glyptina cyanipennis, feeds on Toothed Spurge (Clark et al., 2004). Some aphids feed on spurges (Euphorbia spp.) and probably Toothed Spurge as well; these species include Macrosiphum euphorbiae and Macrosiphum gei (Hottes & Frison, 1931; Cranshaw, 2004). The seeds of spurges are consumed by the Mourning Dove, Greater Prairie Chicken, Bobwhite Quail, and Horned Lark (Martin et al., 1951/1961). Because the milky latex in the foliage can irritate the mouth parts and gastrointestinal tract of mammalian herbivores, it is rarely consumed by them. Photographic Location: The photographs were taken at the Windsor Road Prairie in Champaign, Illinois. Comments: Sometimes this plant is referred to as Euphorbia dentata. Toothed Spurge is closely related to Wild Poinsettia (Poinsettia cyathophora); this latter plant also occurs in Illinois. Wild Poinsettia has upper leaves and bracts that turn red at their bases near the inflorescence; it is the showier of the two plants. Both of these plants are rather weedy in their habits.
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Miss Chen
2018年02月06日
Miss Chen
Description: This perennial orchid is 1-3' tall and unbranched. The central stem is light green and glabrous. Along this stem, there are 2-5 alternate leaves up to 8" long and 2" across; these leaves become smaller in size as they ascend the stem and they are held more or less upright. The leaf blades are light to medium green, lanceolate-oblong to narrowly ovate, and smooth along their margins; their veins are parallel. The central stem terminates in an elongated raceme of flowers about 3-8" long and 2½" across. Racemes of Flowers The flowers are arranged somewhat densely all around the central stalk of the raceme, blooming from the bottom to the top. The flowers are usually bright rose-purple and less often pale rose-purple. Each flower is about 1" long and ¾" across, consisting of 3 petal-like sepals, 3 petals, the reproductive organs, and a nectar spur in the back (about 1" long) that nods downward. The upper sepal and two upper petals (about ¼" long) form a small hood (upper lip) above the reproductive organs. The lowest petal forms the lower lip of the flower (about ¾" long); it is deeply divided into 3 fan-shaped lobes that are barely fringed along their lower margins. The central lobe of the lower lip is larger than the lateral lobes; it usually has a small narrow notch in the middle of its lower margin. The lower sepals are about 1/3" long and form the sides of the flower; they extend further back than either the hood or the lower lip. Each flower has a stout ascending pedicel about 1" long. At the base of each pedicel, there is an ascending small bract (about ¾" long) that resembles a narrow leaf. The blooming period occurs during mid- to late summer and lasts about 3 weeks. Fertile flowers are replaced by erect seed capsules about ½–¾" long that are ellipsoid in shape. The capsules split open to release numerous tiny seeds that are dispersed by the wind. The root system consists of fleshy fibrous roots. Cultivation: The preference is full sun to light shade, moist conditions, and a slightly acidic soil that contains loam, silt, or gravel. Because the root system forms a symbiotic relationship with underground fungi, individual plants are difficult to transplant. During some years, this orchid may fail to flower. Range & Habitat: Purple Fringeless Orchid is uncommon in southern and SE Illinois, while in other areas of the state it is absent. This is a native wildflower of Illinois. Habitats include moist meadows and prairies, prairie swales, openings in floodplain woodlands, swamps, moist thickets, gravelly seeps, streambanks, poorly drained fallow fields, and ditches. This orchid benefits from disturbance that reduces overhead trees and other kinds of competing vegetation. It is often found in seasonal wetlands that are flooded during the spring, but dry out during the summer. Faunal Associations: The nectar of the flowers attracts primarily large butterflies and Sphinx moths. The following floral visitors of Purple Fringeless Orchid have been observed: Danaus plexippus (Monarch), Papilio glaucus (Tiger Swallowtail), Papilio troilus (Spicebush Swallowtail), Speyeria cybele (Great Spangled Fritillary), Epargyreus clarus (Silver-Spotted Skipper), Amphion floridensis (Nessus Sphinx), Hemaris diffinis (Snowberry Clearwing), Hemaris thysbe (Hummingbird Clearwing), and Hyles lineata (White-Lined Sphinx). Various mammalian herbivores (deer, rabbits, cattle, etc.) sometimes browse on the foliage and flowers of this and other orchids. It may be necessary to place wire cages around individual plants or erect fences to prevent the destruction of local orchid populations by these animals. Photographic Location: A prairie in Fayette County, Illinois. The photograph of the flowering plant was taken by Keith & Patty Horn (Copyright © 2009). Comments: When this orchid is in full bloom, it is very eye-catching and beautiful. The only other species in Illinois that are even remotely similar, viz. Platanthera psycodes (Purple-Fringed Orchid) and Platanthera grandiflora (Large Purple-Fringed Orchid), have rose-purple flowers with strongly fringed lower lips. Because these latter orchids are found only in the northern section of the state, their ranges do not overlap with the more southern range of the Purple Fringeless Orchid.
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Miss Chen
2018年02月06日
Miss Chen
Description: This perennial plant is about 1-2' tall, forming a single central stem with occasional short side stems. The alternate light green leaves are up to 6" long and 1½" across, and become smaller in size as they ascend the stem. They are lanceolate or narrowly lanceolate, and sparsely distributed overall. The lowest leaves clasp the stem, while the middle and upper leaves are sessile or have short petioles. They have smooth edges and texture, with faint parallel veins. Blooming Plant in Prairie The central stem terminates in a raceme of flowers, often with a half-dozen or more blooming at the same time. One or two smaller sides stem may each produce racemes of flowers as well. Each flower is about 1½" long and 1" across, consisting of 3 greenish white sepals and 3 white petals. The upper sepal and two upper petals form a hood over the pollen- and nectar-bearing organs of the flower. The lateral sepals are similar in shape, but spread outward. The large white lower petal, or lip, is divided into 3 parts and heavily fringed. There is a long nectar spur that arches downward from the back of the flower. During the day, the flowers have a slight fragrance, which probably becomes stronger at night. The blooming period occurs during early to mid-summer, and lasts about a month. There is a dense cluster of roots that are fleshy and tuberous. They form a symbiotic relationship with endomycorrhizal bacteria, and rarely form offshoots. The tiny seeds are easily carried aloft by the wind, and can travel a considerable distance.
Cultivation: The preference is full sun to light shade, and moist conditions. The soil should be high in organic matter, preferably with a little sand, and the pH should be mildly acid to neutral. However, this orchid is more robust than most and will tolerate conditions that deviate somewhat from the above. Germinating the tiny seeds normally requires the presence of an appropriate fungus, which they invade. Artificial techniques have been developed to speed up the propagation of orchids. Large transplanted plants from a specialist nursery are the easiest to handle and have the best survival rate, but they are expensive, if available at all. Range & Habitat: The Prairie White-Fringed Orchid occurs in scattered counties of central and northern Illinois (see Distribution Map), where it is native. Only small, local populations of this rare plant exist in high quality habitats. It is listed as 'endangered' by the state of Illinois, and is considered 'threatened' by the U.S. government. Habitats include moist to mesic black soil prairies, sand prairies, thickets, pot hole marshes, and fens. At one time, this orchid was far more common, and hundreds of plants could be observed blooming in prairie habitat, particularly near the Chicago region. Habitat destruction and over-collection brought this joyful abundance to an end.
Faunal Associations: Various species of Hawkmoths pollinate the flowers. While seeking the copious nectar, a moth may acquire some pollen on its head, which is then carried to the next plant in bloom. One observed visitor of this orchid is Xylophanes tersa (Tersa Sphinx). Mammalian herbivores will readily consume this plant if they encounter it, including rabbits, deer, and livestock. It may be necessary to protect this plant with a wire cage where such animals are present. Photographic Location: A prairie in east-central Illinois. Comments: This is one of the most beautiful wildflowers in a prairie. Rejoice should you discover one or two plants in bloom. There is a slightly larger orchid, Platanthera praeclara, with a similar appearance, that occurs in prairies west of the Mississippi River.
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Miss Chen
2018年02月06日
Miss Chen
Description: This perennial orchid is 1-2½' tall and unbranched. The central stem is light green, terete, glabrous, and somewhat stout. There are 2-5 alternate leaves along each stem, developing from sheaths. They are 2-8" long and ½–2" across, becoming smaller as they ascend the central stem. The light to medium green leaf blades are elliptic, elliptic-oblong, or lanceolate-oblong in shape and smooth along their margins; their veins are parallel. In relation to the stem, the leaf blades are nearly erect and slightly spreading. The central stem terminates in a narrow raceme flowers about 3-8" long. The whitish or yellowish green flowers are arranged all around the central stalk of the raceme on ascending stout pedicels about 1" long. At the base of each pedicel, there is a linear-lanceolate bract about ¾" long. Raceme of Flowers Each flower is about ¾" long and across, consisting of 3 petals, 3 sepals, a nectar spur, and reproductive organs. The upper sepal and upper 2 petals (about ¼" long) form a small hood (upper lip) over the reproductive organs and nectary opening. The upper sepal is broadly oblong in shape, while the upper 2 petals are linear to linear-oblong. The 2 lateral sepals (about ¼" long) are broadly oblong and usually curve backward from the front of the flower. The lower petal forms a lower lip that is deeply divided into 3 fan-shaped lobes. The lateral lobes and usually the central lobe are deeply fringed; less often, the central lobe is shallowly divided into 2-3 smaller lobes. The fringed lower lip may be more white than other parts of the flower. At the back of the flower, there is a narrowly cylindrical nectar spur about ¾" long that nods downward. The blooming period occurs during mid-summer and lasts about 3 weeks. The flowers are often fragrant, especially at night. Fertile flowers are replaced by narrowly ellipsoid seed capsules about ¾" long. The seed capsules split open to release numerous tiny seeds, which are distributed by the wind. The root system consists of fleshy fibrous roots. Sometimes, vegetative offsets develop a short distance from the mother plant. Cultivation: The preference is full or partial sun, moist conditions, and an acidic soil containing sand, silt-loam, peaty material, or some gravel. Like other orchids, this species requires the appropriate endomycorrhizal fungus in the soil for proper growth and development. It can be difficult to transplant successfully. Range & Habitat: The native Green-Fringed Orchid has been found in most areas of Illinois, particularly the NE section of the state; it is relatively uncommon. Habitats include moist prairies and sand prairies, sandy swamps, moist open woodlands, shrubby bogs, acidic gravelly seeps, low areas along streams, sandy fields, powerline clearances, and ditches. Green-Fringed Orchid is more likely to appear in degraded areas than many other orchids, although it also occurs in higher quality habitats. Faunal Associations: The flowers are pollinated primarily by moths, including Noctuid moths and Sphinx moths. Such species as Anagrapha falcifera (Celery Looper Moth), Allagrapha aerea (Unspotted Looper Moth), and Hemaris thysbe (Hummingbird Clearwing) have been observed sucking nectar from the flowers. Mammalian herbivores (deer, rabbits, cattle, etc.) sometimes enjoy a gourmet meal by browsing on the foliage and flowers of this and other terrestrial orchids. Photographic Location: A prairie in Fayette County, Illinois. The photograph of the flowering plant was taken by Keith & Patty Horn (Copyright © 2009). Comments: Because of its greenish flowers, this orchid doesn't stand out from the background to the same extent as more colorful orchids in its genus. However, it has a delicate beauty that is peculiarly its own. While there are many orchids in the Midwest that have greenish flowers, this orchid is the only one with a deeply fringed lower lip. Compared to the similar Platanthera leucophaea (Prairie White-Fringed Orchid), the Green-Fringed Orchid has a lower lip with more narrow and insubstantial lobes (this applies particularly to the central lobe). Other species in this genus, e.g. Platanthera blephariglottis (White-Fringed Orchid) and Platanthera ciliaris (Orange-Fringed Orchid), have fringed lower lips that are not divided into major lobes. Thus, not only color, but also subtle differences in floral structure, are important in the identification of an orchid species in this interesting genus.
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