首页
动态
文章
百科
花园
设置
简体中文
已关注
+
关注
动态 (4985)
Miss Chen
2018年05月05日
Miss Chen
Description: This perennial plant is about ¾-2' tall and unbranched or little branched. Scattered white hairs occur occasionally along the central stem, although it becomes glabrous with age. The opposite leaves are up to 5" long and 3" across (excluding the petioles); they are ovate-cordate, dentate along their margins, and largely hairless. The upper leaf surface is medium to dark green and hairless. The slender petioles of the leaves are up to 1½" long and medium green. The central stem terminates in a raceme of flowers up to 6" long. The stalk of this raceme has scattered white hairs. The small flowers are sparsely, but evenly, distributed along this stalk on slender pedicels up to ½" long. These pedicels spread outward. Each flower consists of 2 white petals, 2 green sepals, 2 stamens, and a slender style. Each petal is deeply divided into 2 lobes. At the base of each flower, there is a 2-celled ovary that is green and covered with stiff hooked hairs; it is obovoid in shape. Each cell of this ovary contains a single seed. The blooming period for a colony of plants occurs during the summer and lasts about a month. Each flower is short-lived and replaced by a small bur-like fruit (see the description of the ovary above). The root system can produce rhizomes or stolons that extend through the soil or leaf mould to create clonal offsets from the mother plant. Cultivation: The preference is dappled sunlight to medium shade, more or less mesic conditions, and a rich loamy soil with abundant organic matter.
Range & Habitat: The native Enchanter's Nightshade is an occasional to locally common plant that occurs in most counties of Illinois (see Distribution Map). This plant may be less abundant than in the past because of browsing by deer. Habitats include mesic deciduous woodlands, including oak woodlands and maple/basswood woodlands, and areas that are adjacent to woodland paths. Sometimes this species occurs in wooded upland areas and along ravine slopes. Faunal Associations: The nectar and pollen of the flowers attract small bees, including Halictid bees (Lasioglossum spp.) and little carpenter bees (Ceratina spp.); they are also visited by Syrphid flies and bee flies (Bombyliidae). The caterpillars of a moth, Mompha terminella (Enchanter's Cosmet), are blotch leaf-miners. Birds and mammals help to distribute the seeds, as the small bur-like fruits can cling to feathers and fur; these fruits can cling to the clothing of humans as well. Deer occasionally browse on the foliage of Enchanter's Nightshade.
Photographic Location: A mesic deciduous woodlands at Busey Woods in Urbana, Illinois. Comments: This is one of the woodland wildflowers that blooms during the summer in shaded areas. The flowers of such species are usually small, white, and not very showy. Enchanter's Nightshade is a rather odd member of the Evening Primrose family, as its flowers have only 2 petals, 2 sepals, and 2 stamens. This is a distinctive characteristic of the Circaea genus in this family. The only other member of this genus that occurs in Illinois, Circaea alpina (Small Enchanter's Nightshade), is an uncommon species that is restricted to the cool moist woodlands of northern Illinois. It has leaves that are more cordate and indented at the base, and its flowers are clustered toward the apex of the flowering stalk (rather than being evenly distributed along this stalk). While Enchanter's Nightshade is ¾-2' tall and it has 2-celled ovaries, Small Enchanter's Nightshade is less than 1' tall and it has 1-celled ovaries.
0
0
文章
Miss Chen
2018年05月05日
Miss Chen
Description: This herbaceous perennial wildflower is 3-7' tall. The stems are light green and hairless, while the large compound leaves are bipinnate or tripinnate with 10 or more leaflets. Usually 3 or 5 leaflets are grouped together in the ultimate partitions of each compound leaf. Individual leaflets are up to 4" long and 3" across; they are medium green, glabrous, and lanceolate to broadly ovate in shape. The margins of these leaflets are coarsely toothed; the terminal leaflets are often shallowly to deeply cleft. Each plant produces one or more panicles of racemes about 1-3' long. These panicles are very narrow and produce only a few secondary racemes around the central raceme. The racemes are narrowly cylindrical in shape and erect; they are densely covered with flowers, buds, and fruits (follicles) in varying stages of development (buds on top, flowers in the middle, and fruits below). Individual flowers span about 2/3" across and they are completely white, consisting of about 24 stamens, a single pistil, and insignificant sepals that drop early. The slender stamens are long and conspicuous, while the pistil has a short curved tip. Each flower has a short pedicel. The blooming period occurs during early to middle summer and lasts about 1½ months. The flowers have an odd unpleasant scent. Each flower is replaced by a small follicle about 1/3" long; this follicle hasDistribution Map a beak that is very short and usually curved. Each follicle splits open along one side to release several seeds; these seeds are fairly smooth (not conspicuously scaly). The root system is rhizomatous and fibrous. Cultivation: The preference is partial sun to medium shade, mesic conditions, and a rich loamy soil with abundant organic material. This plant requires plenty of space. Range & Habitat: The native Black Cohosh is rare in Illinois and state-listed as 'endangered.' It has been found in only a few counties in northern and southern Illinois. At some of these localities, Black Cohosh is probably extirpated because it hasn't observed since the late 19th century. At other localities, the population consists of plants that have been introduced. Habitat includes mesic deciduous woodlands (where Sugar Maple is often dominant) and the bases of bluffs along rivers. In Illinois, Black Cohosh is more common in flower gardens than the wild; it is also more common in natural areas further to the east, including the Appalachian mountains. Faunal Associations: The flowers provide both nectar and pollen to insect visitors. Unfortunately, these insects are largely unknown, in part because Black Cohosh is uncommon in Illinois and neighboring states. The caterpillars of the butterfly Celastrina neglecta major (Appalachian Azure) feed exclusively on Black Cohosh; however, this insect doesn't occur in Illinois. It is doubtful that mammalian herbivores feed on this wildflower to any significant degree because the foliage is toxic. Photographic Location: A flower garden at The Arboretum in Urbana, Illinois. Comments: This is one of the largest woodland wildflowers. Black Cohosh is attractive as a wildflower in part because it produces showy spikes of white flowers during the summer, when there is little else in bloom in wooded habitats. For this reason, it's a pity that this species isn't more common within the state. There are two other species that Black Cohosh can be confused with. One of them, Cimicifuga rubifolia (Appalachian Bugbane), has leaflets up to 10" long and across that often display a maple-leaf shape; it also has fewer than 10 leaflets per compound leaf.
In contrast, Black Cohosh has smaller leaflets (up to 4" long and 3" across) and there are usually more than 10-20 leaflets per compound leaf. Another species, Cimicifuga americana (American Bugbane), has foliage that is nearly identical to that of Black Cohosh. However, American Bugbane has several pistils in the center of each flower, while Black Cohosh has only a single pistil per flower. Similarly, American Bugbane produces its follicles in clusters (one for each pistil), while Black Cohosh produces its follicles individually.
0
0
文章
Miss Chen
2018年05月05日
Miss Chen
Description: This wildflower has evergreen leaves and semi-woody stems. The entire plant, including the inflorescence, is about 6-10" tall. Plants without an inflorescence are only 3-5" tall. The central stem of each plant is red to brown, unbranched, glabrous, and more or less terete. One or two pairs of smaller opposite leaves occur near the base of the stem, while a single whorl of three larger leaves occur at the base of the inflorescence. The leaves are 1-3" long, ¼–1" across, rather leathery in texture, and glabrous; they are lanceolate to ovate in shape, while their margins have widely spaced dentate teeth. The upper leave surface is dark green, except in areas along the veins, where it is white; this provides the upper leaf surface with a pinnately striped appearance. The lower leaf surface is light green. The petioles of these leaves are short and slender. On fertile plants, the stem terminates in an inflorescence consisting of a nodding umbel, or nodding umbel-like cyme, of 2-5 flowers on a long unbranched peduncle (flowering stalk). Sometimes the inflorescence produces only a single nodding flower. The erect peduncle is pinkish red to light brown, relatively stout, terete, and short-pubescent; the pedicels of individual flowers are similar, except they are shorter (about 1" long) and strongly recurved, holding the flowers face-down. Each flower is about ½–¾" across, consisting of 5 white petals, 5 light green sepals, 10 stamens, and a green pistil. The petals are oval in shape and concave toward the face of the flower. The sepals are oval-ovate in shape and less than one-half of the length of the petals. The stamens have showy light pink anthers and very short filaments; the anthers are bifurcated, releasing pollen from round pores at their tips. The pistil consists of a superior ovary, a short style, and large stigma (all green). The ovary is subgloboid in shape and slightly 5-lobed. The style has a short obconic shape with a broad flat tip and even broader base. The stigma is dome-shaped and wider than the style. The blooming period occurs from late spring to early summer, lasting about 2 weeks. The flowers are fragrant. Afterwards, the flowers are replaced by seed capsules that are about 8 mm. (1/3") across and dark brown at maturity; they have the same shape as the ovary. The sepals persist underneath these seed capsules. When these capsules split open from above, they release many fine seeds. The root system consists of brown fibrous roots and underground white stolons; the latter are long and slender. Clonal plants are often produced from the stolons. Cultivation: The preference is partial sun to medium shade, dry-mesic conditions, and an acidic soil containing some rocky material or sand. Growth and development are relatively slow. The seeds are difficult to germinate, although new plants can be created by dividing the root systems of older plants. In order to flourish, however, the presence of an appropriate mycorrhizal fungus in the soil may be required. Range & Habitat: Striped Wintergreen is a rare native plant in Illinois, where it is state-listed as 'endangered.' It has been found in only two counties (Cook County and Pope County) within the state; see the Distribution Map. At the present time, it may be extirpated from Cook County because of development. Illinois lies along the NE range-limit of this plant; it is more common in mountainous areas further to the east and southeast. In Illinois, habitats consist of rocky upland woodlands and sandy upland woodlands; the latter habitat occurs along Lake Michigan. In these habitats, oaks (Quercus spp.) are usually the dominant canopy trees. Outside of Illinois, this plant is often found in mixed woodlands and coniferous woodlands. Striped Wintergreen is restricted to high quality natural areas in Illinois.
Faunal Associations: The flowers are cross-pollinated primarily by bumblebees; honeybees also visit the flowers (Standley et al., 1988). These insects obtain nectar from the flowers. The foliage of Striped Wintergreen is regarded as toxic to sheep (Schaffer, 1904), and White-tailed Deer usually avoid it when there are better sources of food (Rawinski, 2016). Photographic Location: A wooded area in the southern Appalachian mountains. The photographs were taken by Paul Showers (Copyright © 2016). Comments: Both the foliage and flowers are quite ornamental. In Illinois, the closest relative of Striped Wintergreen is Pipsissewa (Chimaphila umbellata). This latter plant can be distinguished by its leaves: 1) they are oblanceolate in shape, 2) the margins of its leaves are more finely and abundantly toothed, and 3) its leaves lack the white markings that are found on the leaves of Striped Wintergreen. The inflorescence of Pipsissewa also tends to have more flowers (4-8) than the inflorescence of Striped Wintergreen. The common name, 'Wintergreen,' refers to the evergreen leaves, as the leaves of Striped Wintergreen do not possess a mint-like fragrance. Thus, Striped Wintergreen should not be confused with another low-growing semi-woody plant, Wintergreen (Gaultheria procumbens). In addition to the fragrance of its leaves, this latter plant differs by its white bell-shaped flowers, red berries, and toothless leaf margins. Other common names of Chimaphila maculata are Spotted Wintergreen, Spotted Prince's Cone, Striped Prince's Cone, Spotted Pipsissewa, and Striped Pipsissewa.
0
0
文章
Miss Chen
2018年05月05日
Miss Chen
Description: This annual plant is about ½–4' tall. Medium to large plants (greater than 1½' tall) branch occasionally, while small plants (less than 1½' tall) are often unbranched. The central and lateral stems are hairless. Alternate leaves are up to 6" long and 4" across; they are ovate or deltoid-ovate with 2-4 large teeth along their margins. These teeth are pointed and widely spaced. The uppermost leaves are moreFlowering Plants narrow and may have only 0-1 teeth along their margins. The widely spreading leaves are medium to dark green and hairless; they are not white-mealy on their undersides. The leaf tips are pointed, while their bases are truncate or slightly indented. The slender petioles are up to 1" long. The central stem and upper lateral stems terminate in panicles of sessile clustered flowers. In addition to these, there are usually secondary panicles that develop from the axils of the upper leaves. The branches of these panicles can be hairless or conspicuously hairy. Individual flowers are green or greenish white and only 1/8" (3 mm.) across, consisting of 5 sepals, 5 stamens, and a flattened ovary with a pair of tiny styles at its apex. There are no petals. The sepals are ovate and slightly keeled. The blooming period can occur from late spring into the fall. On an individual plant in bloom, the flowers are at different stages of development. Pollination is by wind. The persistent sepals only partially cover the developing seeds; there is only one seed per flower. Each seed is covered with a thin membrane that is easily removed. Individual seeds are flattened, circular in circumference, and shiny black; they are 1.5–2.0 mm. across. The root system consists of a taproot. This plant spreads into new areas by reseeding itself. Cultivation: The preference is dappled sunlight to medium shade and mesic to dry conditions. While this plant is usually found on rocky ground, it will adapt to ordinary garden soil. Depending on the fertility of the soil and moisture conditions, the size of individual plants can vary considerably. Range & Habitat: Maple-Leaved Goosefoot is uncommon to occasional in most areas of Illinois, except in the east-central section of the state, where it is rare or absent (see Distribution Map). This is a native plant. Habitats include rocky upland woodlands, shaded or semi-shaded ledges of cliffs, bottoms of thinly wooded bluffs, recently logged or burned woodlands, woodland openings, shaded to semi-shaded areas of rocky glades, thickets, and fence rows. Maple-Leaved Goosefoot is often found in high quality habitats, but it also occurs in disturbed areas. This is one of the less weedy Chenopodium spp. Faunal Associations: Little is known about floral-faunal relationships for this unusual woodland plant, although several moths, skippers, and leaf beetles are known to feed on Chenopodium spp. primarily in weedy open areas. The Bobwhite and several sparrows eat the seeds of these species, while White-Tailed Deer occasionally browse on the foliage.
Photographic Location: Ledge of a sandstone cliff at the Portland Arch in west-central Indiana. Comments: Maple-Leaved Goosefoot (Chenopodium simplex) has very distinctive leaves, which makes it is easy to recognize. These leaves are usually larger in size than those of many other Chenopodium spp., and they usually have 1-4 pairs of widely spaced large teeth. Other Chenopodium spp. have leaves with smaller teeth or their leaves lack teeth altogether. Unlike Maple-Leaved Goosefoot, these latter species often have white-mealy leaf undersides, white-mealy upper stems, and/or white-mealy sepals. They are usually found in sunny disturbed areas rather than woodlands. The American species, Maple-Leaved Goosefoot (Chenopodium simplex), closely resembles a European species with the same common name, Chenopodium hybridum (Maple-Leaved Goosefoot), but it has a different number of chromosomes. The American species is sometimes referred to as Chenopodium gigantospermum, which refers to its relatively large seeds for species in this genus.
0
0
文章
Miss Chen
2018年05月05日
Miss Chen
Description: This perennial wildflower is 1-3' tall and unbranched. The erect central stem is light green to pale purple, terete, glabrous, and often glaucous. A non-flowering plant has a single compound leaf at the apex of this stem, while a flowering plant has two compound leaves. The lower compound leaf of a flowering plant is located toward the middle of the central stem, where it is divided into a whorl of 3 compound leaflets. Each compound leaflet is ternately divided into 9 simple subleaflets that are arranged in groups of 3 (2 lateral groups and a terminal group). Less often, a compound leaflet may be divided into 15 simple subleaflets that consist of 2 additional lateral groups. The basal stalks (petiolules) of the compound leaflets are long and ascending; they are light green and glabrous. The subleaflets are 1-3" long and ¾-2" across (or occasionally wider); they are broadly ovate-oblong to obovate-oblong in shape and smooth along their margins, terminating in 2-5 cleft lobes with blunt tips. The upper surface of the subleaflets is glabrous and either gray-green, yellowish green, or medium green, while the lower surface is pale green and glabrous. The slender basal stalklets of the subleaflets are light green and glabrous. The upper compound leaf of a flowering plant is located under the inflorescence. This compound leaf resembles the lower compound leaf, except its 3 compound leaflets are smaller in size because they have only 3 subleaflets each. On a flowering plant, the central stem terminates in a floral panicle about 1-3" long that is rounded or elongated; each panicle usually has 5-30 flowers (rarely more). Individual flowers are about 1/3" (8 mm.) across, consisting of 6 petaloid sepals, insignificant petals, 6 stamens, and an ovoid ovary with a beak-like style. Depending on the local ecotype, the oblanceolate sepals are greenish yellow, greenish brown, or greenish purple. Underneath each flower, there are 3-4 green bractlets that resemble sepals. The branching stalks of the panicle are light green, glabrous, and ascending. The blooming period occurs from mid- to late spring before the leaves have fully developed. Afterwards, the flowers are replaced by berry-like seeds that are about 1/3" across, globoid in shape, glabrous, and glaucous. These seeds are initially green, but they later become bright blue at maturity during the summer. The seed coat is fleshy and contains carbohydrates. The root system is rhizomatous and fibrous. Cultivation: The preference is dappled sunlight during the spring, followed by light shade during the summer, at a location that has average moisture levels and fertile loamy soil. The soil should also contain abundant organic matter from decaying leaves and other plant materials, as typically occurs underneath trees. The large seeds are difficult to germinate. However, once it becomes established at a favorable site, Blue Cohosh is long-lived. Range & Habitat: The native Blue Cohosh occurs occasionally in central Illinois, northern Illinois, and the Shawnee Hills of southern Illinois. In other areas of southern Illinois, this wildflower is uncommon or absent. Habitats include rich mesic woodlands, bluffs, and wooded slopes of large ravines. This relatively conservative wildflower can be found in woodlands dominated by either oaks or maples where the native ground flora is still intact. Faunal Associations: Both pollen and nectar are available as floral rewards to insect visitors. These visitors include miscellaneous flies (Syrphid, Tachinid, Muscid, etc.), parasitoid wasps (Braconid, Ichneumonid, etc.), small Halictid bees (Lasioglossum spp., etc.), and bumblebees (Robertson, 1929; Hannan & Prucher, 1996). Apparently, very few insects feed destructively on the foliage and other parts of Blue Cohosh. Caterpillars of the moth Clepsis melaleucana (Black-Patched Clepsis) and the plant bug Metriorrhynchomiris dislocatus have been observed to feed on this plant (Covell, 1984/2005; Knight, 1941). Both of these insects are polyphagous. Among vertebrate animals, both the White-Footed Mouse and Woodland Deer Mouse feed on the berry-like seeds of Blue Cohosh (Hamilton, 1941). However, because of the bright blue coloration of the fleshy seed coats and their carbohydrates, woodland birds are probably the primary dispersal agents of the seeds, which are known to be toxic to humans. Because the bitter-tasting foliage of this wildflower contains toxic glycosides and alkaloids, it is rarely eaten by White-Tailed Deer and other mammalian herbivores. Photographic Location: A wooded bluff in Vermilion County, Illinois.
Comments: Generally the subleaflets (or simple leaflets) of Blue Cohosh are remarkably similar in appearance to those of Meadow Rue species (Thalictrum spp.), except they are often grayish green or yellowish green and tend to have more terminal lobes (2-5) than the latter. However, the flowers and berry-like seeds of Blue Cohosh are quite different from those of Meadow Rue species, and they belong to separate plant families. In addition to the typical variety of Blue Cohosh that is described here, there is also a more eastern variety of this wildflower that is referred to as Giant Blue Cohosh (Caulophyllum thalictroides giganteum). Thus far, Giant Blue Cohosh has not been found in Illinois. It differs from the typical Blue Cohosh in having slightly larger flowers (about ½" across) that are deep mauve or purple; these flowers bloom about two weeks earlier before its foliage has unfolded. The subleaflets of Giant Blue Cohosh are slightly larger in size as well. It is often classified as a distinct species, Caulophyllum giganteum.
0
0
文章
Miss Chen
2018年05月04日
Miss Chen
Description: This plant is a winter annual or biennial up to 2½' tall that branches occasionally. A few basal leaves are produced during the fall, while alternate cauline leaves develop along the stems during the following spring. The stems are green, glabrous, and terete. The leaves are up to 4" long and ¾" across; they are pinnately compound with 3-15 leaflets. The leaflets are linear, oblanceolate, obovate, or orbicular in shape, becoming more narrow on the upper leaves; their margins are usually undulate, shallowly lobed, or dentate with a few blunt teeth. On each leaf, the terminal leaflet is as wide or wider than the remaining leaflets. Both the lower and upper sides of the leaves are green and glabrous. The upper stems terminate in racemes of small white flowers. Each flower is about 3 mm. (1/8") long, consisting of 4 white petals, 4 light green sepals, a stout pistil, and several stamens. The mature pedicels (5-9 mm. in length) ultimately become longer than the flowers. Both the pedicels and the central stalk (rachis) of the raceme are green and glabrous. The blooming period occurs from mid-spring to early summer and lasts about 1-2 months. Each flower is replaced by a narrowly cylindrical seedpod (or silique) that is up to 1¼" long. The siliques are relatively straight and they spread outward slightly from the central stalk of each raceme. The tips of young siliques often surround the flowers and partially obscure them. Each silique contains a row of tiny seeds; these seeds are about 1 mm. in length, oblongoid-ovoid in shape, and brown. The root system consists of a tuft of shallow fibrous roots. This plant spreads by reseeding itself.
Cultivation: The preference is light shade to partial sun, wet to moist conditions, and soil containing loam or sandy loam with decaying organic matter. This plant develops quickly during the spring when the weather is cool and moist. Range & Habitat: The native Pennsylvania Bitter Cress occurs occasionally in most areas of Illinois; it tends to be less common or absent in the NW corner of the state (see Distribution Map). Habitats include wet to mesic deciduous woodlands (especially floodplain and bottomland woodlands), swamps, shady seeps and springs, the bottom of cliffs, low ground near streams, and areas along woodland paths. Pennsylvania Bitter Cress is occasionally found in slow-moving water of seasonal ditches and shallow streams, where it resembles an emergent-aquatic plant. This plant is found in both higher quality habitats and disturbed areas where there is partial to light shade and the ground is more or less moist. It is sometimes found in sandy areas where decaying organic material is abundant.
Faunal Associations: Occasionally, small bees or flower flies (Syrphidae) visit the flowers, otherwise they attract few visitors. Caterpillars of the moth Evergestis pallidata (Purple-Backed Cabbage Worm) are known to feed on the foliage of Cardamine spp. (Bitter Cresses), while caterpillars of the butterfly Anthocharis midea (Falcate Orangetip) feed on the flowers, buds, and developing seedpods of these plants. Two aphids, Myzus cerasi (Black Cherry Aphid) and Rhopalosiphonius staphyleae (Mangold Aphid), use these plants as summer hosts. Information about floral-faunal relations for vertebrate animals is currently unavailable. Photographic Location: Near or in a stream of a sandy woodland at the Indiana Dunes State Park in NW Indiana.
Comments: This spring wildflower of woodlands is not very showy and it is often overlooked. This plant has a similar appearance to other Bitter Cresses (Cardamine spp.) with small white flowers, including Cardamine hirsuta (Hairy Bitter Cress) and Cardamine parviflora arenicola (Small-Flowered Bitter Cress). Hairy Bitter Cress, an introduced species, is hairy toward the base and it has abundant basal leaves while the flowers are blooming. Pennsylvania Bitter Cress has very few, if any, basal leaves while the flowers are blooming, and its foliage is completely hairless (at least in Illinois). Small-Flowered Bitter Cress is usually a little smaller in size than Pennsylvania Bitter Cress and it has more narrow leaflets (up to ¼" across). The terminal leaflets of this species are about the same size as the non-terminal leaflets. Small-Flowered Bitter Cress is usually found in habitats that are drier and sunnier than Pennsylvania Bitter Cress, although it is occasionally found in moist woodlands and wetlands as well.
0
0
文章
Miss Chen
2018年05月04日
Miss Chen
Description: This perennial wildflower is 4-12" tall and unbranched, except for possibly 1-2 flowering side stems near the apex. The erect central stem is light green to purplish green, terete, and hairy. At the base of each plant, 1-2 basal leaves are commonly present; they are about 1" long and across,Close-up of Flowers cordate-orbicular, and bluntly dentate or undulate along their margins. Each basal leaf has a long slender petiole. The alternate leaves are up to 2" long and 1" across; they are oval-ovate to oblong, bluntly dentate or undulate along the margins, and ciliate. At the base, the alternate leaves are sessile or slightly clasp the central stem. The alternate leaves become slightly shorter and more narrow as they ascend the stem. The central stem terminates in a raceme of flowers. The flowers and buds are concentrated toward the apex of the raceme, while cylindrical seedpods (siliques) develop along the remainder of the raceme. Each flower is about ½–¾" across, consisting of 4 petals, 4 sepals, several stamens, and a single stout style of the pistil. The petals are pale purple or purple-tinted white and obovate in shape. The sepals are purple, hairy, and membranous-white along their margins. The petals are much longer than the sepals. The blooming occurs during mid-spring and lasts about 2 weeks. The flowers are fragrant. Each flower is replaced by an ascending silique up to 1" long. The 2-valved siliques are green to purple; each silique contains a single row of seeds and it has a stout pedicel up to 1" long at its base. Eventually, the silique splits in half lengthwise to release the seeds. The root system is fibrous and tuberous. Cultivation: This wildflower develops early during the spring when it receives dappled sunlight from its location underneath deciduous trees. It likes an evenly moist site with fertile loamy soil and abundant leaf mold. By the beginning of summer, it has already died down and released its seeds. Range & Habitat: The native Purple Cress is occasional in NE and east central Illinois, but it is rare or absent elsewhere in the state (see Distribution Map). Habitats include moist deciduous woodlands, low wooded valleys, and areas along shaded seeps and springs, particularly where limestone comes close to the surface of the ground. This conservative species is normally found where the original ground flora is still intact. It is one of the spring wildflowers in woodlands that is threatened by the spread of Alliaria petiolata (Garlic Mustard).
Faunal Associations: Records about floral-faunal relationships for this species are limited. Insect visitors of the flowers are probably similar to those of a closely related species, Cardamine bulbosa (Spring Cress), which blooms only a little latter and occupies similar habitats. These insects include various kinds of bees (honeybees, mason bees, Andrenid bees, Halictid bees), bee flies (including Bombylius major, the Giant Bee Fly), other miscellaneous flies, and butterflies that appear during the spring. Most of these insects suck nectar from flowers, although some of the bees and flies also seek pollen. An oligolectic flea beetle that prefers woodland habitats, Phyllotreta bipustulata, feeds on the foliage of Purple Cress; it also feeds on the foliage of Dentaria spp. (Toothworts). Mammalian herbivores rarely feed on this wildflower because its foliage is short-lived and unpleasant-tasting (bitter and spicy). Photographic Location: Along a shaded seep in Vermilion County, Illinois. Comments: This is another lovely spring wildflower of the woodlands. Purple Cress is similar to Cardamine bulbosa (Spring Cress), except that the latter has flowers with white petals and green sepals. Spring Cress also has a glabrous central stem, while Purple Cress has a hairy stem. In contrast to Dentaria spp. (Toothworts) and many other Cardamine spp. (Bitter Cress species), both of these wildflowers lack compound leaves that are pinnately or palmately divided. Another species of the Mustard family, Iodanthus pinnatifidus (Purple Rocket), produces pale purple flowers on long racemes in damp wooded areas. However, Purple Rocket is a larger plant that blooms later in the year (late spring to mid-summer). Other common names of Cardamine douglassii are Purple Spring Cress and Northern Bitter Cress.
0
0
文章
Miss Chen
2018年05月04日
Miss Chen
Description: This perennial wildflower is ½–1½' tall with an erect stem that is unbranched or sparingly branched toward the apex where the inflorescence occurs. The central stem is medium green, glabrous, and terete; it occasionally has fine longitudinal ridges. There are both basal leaves and alternate leaves. The blades of the basal leaves are up to 1¼" long and 1" across; they are oval to orbicular in shape,Raceme of Flowers medium green, glabrous, and smooth or undulate along their margins. The slender petioles of the basal leaves are usually longer than the blades. The alternate leaves are produced sparingly along the central stem; they are up to 2" long and 1" across, medium green, and glabrous. The alternate leaves are oblong-ovate in shape and their margins are smooth, undulate, or bluntly dentate; at the base, each alternate leaf is sessile or short-petioled. The central stem terminates in a raceme of flowers; the flowers usually bloom in the upper half of the raceme, while their siliques (narrowly cylindrical seedpods) develop below. Each flower consists of 4 petals, 4 sepals, 6 stamens, and a pistil with a single style; when the flower is fully open, it spans about ½" across. The petals are white with rounded tips. The glabrous sepals are initially green, but they become yellow as they age. The petals are much longer than the sepals. Each flower has a slender pedicel about ½" long. The blooming period occurs from mid- to late spring and lasts about 3 weeks. The flowers are sometimes fragrant. Each flower is replaced by a slender hairless silique about 1" long that is somewhat flattened. The siliques are ascending to erect; they eventually divide into two parts to release their seeds. These seeds are ovoid, somewhat flattened, and wingless; they are arranged in a single row in each silique. Each plant has a swollen tuberous rootstock at the base of the central stem; this tuberous rootstock has spreading fibrous roots that occasionally produce small tubers. New plants are created from either the seeds or tubers. Cultivation: The preference is partial sun or dappled sunlight, wet to moist conditions, and a loose fertile loam with organic material. Shallow standing water is tolerated if it is temporary; full sun is tolerated if the ground is consistently moist. Most growth and development occurs during the spring before the canopy trees leaf out. Range & Habitat: The native Spring Cress is occasional to locally common in most areas of Illinois; it is less common or absent in the SW section of the state (see Distribution Map). This species may be less common than in the past. Habitats include low woodlands along rivers, edges of vernal pools in woodlands, damp depressions in rocky bluffs, woodland seeps and springs, and damp meadows.
Faunal Associations: The nectar of the flowers attracts cuckoo bees (Nomada spp.), mason bees (Osmia spp.), little carpenter bees (Ceratina spp.), Halictid bees (Augochlorella spp., Halictus spp., & Lasioglossum spp.), Andrenid bees (Andrena spp.), bee flies (Bombylius spp.), dance flies (Empis spp.), Syrphid flies (miscellaneous), small- to medium-sized butterflies (miscellaneous), and skippers (miscellaneous). Some of the bees also collect pollen. The flea beetles Phyllotreta oblonga and Phyllotreta bipustulata feed on Spring Cress and other Cardamine spp. (Bitter Cress species). Mammalian herbivores usually avoid the consumption of Spring Cress because its foliage is pungent and somewhat bitter. Photographic Location: A low woodland along the Sangamon river in Piatt County, Illinois. Comments: Spring Cress is one of the more attractive members of the Mustard family as its flowers are fairly large (spanning about ½" across). This wildflower favors the more damp areas of woodlands and it is sometimes found in soggy meadows. Another native species, Cardamine douglassii (Purple Cress), is very similar to Spring Cress. Both species prefer similar habitats, bloom during the spring, and their flowers and foliage are similar to each other. Purple Cress differs from Spring Cress by the purplish-pink tint of its flower petals, sepals that are dark purple and hairy, and stems that are hairy toward the base. It has a tendency to bloom about 2 weeks before Spring Cress. Other Cardamine spp. (Bitter Cress species) in Illinois have either smaller flowers (about ¼" across or less) or at least some of their leaves are deeply divided into lobes (either pinnately or palmately). Spring Cress (and other species in the genus) isn't classified as an Arabis sp. (Rock Cress) because of its wingless seeds; the seeds of Rock Cresses have winged membranous margins of varying widths.
0
0
文章
Miss Chen
2018年05月04日
Miss Chen
Description: This plant is an annual or biennial from 2-6' tall. Usually, it is unbranched, although sometimes a few side stems will develop from the lower central stem. The central stem is light green, terete, slightly grooved, and hairy. The alternate leaves are up to 6" long and 2" across, tapering to slender petioles. They are medium to dark green, elliptic to ovate in shape, and their margins are serrated. The texture of the leaves is somewhat rough; they are hairy along the major veins of their undersides. The central stem terminates in a spike of flowers about ½–2' long. From the axils of the upper leaves, secondary spikes of flowers may develop, but these are much shorter (about 1–6" in length). The rachis (central stalk) of each spike is similar to the central stem. The flowers are about 1" across; their corollas vary in color from light to dark violet-blue, depending on the local ecotype. Each corolla has 5 spreading lobes that are divided nearly to the base; they are ovate to obovate in shape. Each corolla has a satiny appearance under bright light, and it tends to have margins that twist and curl. The corolla is often white toward the center, rather than blue-violet. At the center of the corolla is the apex of a 5-angled ovary from which a light violet style is strongly exerted. This style bends downward from the flower, but curls upward near its tip; the small stigma is white and divided into 3 lobes. Each flower also has 5 stamens. The light green calyx is tubular-campanulate in shape with 5 narrow green ridges and 5 long narrow teeth around its upper rim; these teeth curl backward when the flower opens. The blooming period occurs from mid-summer to early fall, lasting about 1½ months. Afterwards, the flowers are replaced by seed capsules that are 5-angled and rather flat-topped. The root system consists of a taproot.
Cultivation: The preference is light shade to partial sun, moist to mesic conditions, and a rich loamy soil. During a drought, this plant often drops its lower leaves. Depending on moisture conditions and the fertility of the soil, the size of this plant can be highly variable. Range & Habitat: American Bellflower is a common plant that occurs in most counties of Illinois (see Distribution Map), where it is native. Habitats include moist to slightly dry deciduous woodlands, disturbed open woodlands, woodland borders, and thickets. This plant is often found along woodland paths, and it appears to prefer slightly disturbed areas.
Faunal Associations: Long-tongued bees are the primary pollinators of the flowers, including bumblebees and leaf-cutting bees (Megachilidae). Among the latter, is the oligolectic bee Megachile campanulae campanulae. Other visitors of the flowers include Halictid bees, butterflies, and skippers. These insects seek nectar, and some of the bees collect pollen from the anthers. Syrphid flies may feed on the pollen, but they are not effective pollinators. Deer occasionally eat the flowers and foliage. Photographic Location: The edge of a wooded area at Crystal Lake Park in Urbana, Illinois.
Comments: Sometimes this plant is called "Tall Bellflower." The older scientific name is Campanula americana, but it has been reassigned to its own genus because of the unique structure of the flowers. The flowers of this tall-growing plant are showy, but individually short-lived. However, new flowers are produced in succession higher up on the spike. The other members of the Bellflower family that occur in Illinois, whether native or introduced, have bell-shaped (campanulate) flowers, while the flowers of the American Bellflower have a more open design with widely spreading lobes. As a result, this species is easy to identify.
0
0
文章
Miss Chen
2018年05月04日
Miss Chen
Description: This annual plant consists of sprawling stems with pairs of opposite leaves. The stems are up to 5 cm. (2") long; they are whitish green and occasionally branch. The opposite leaves are 3-4 mm. long and about half as much across; they are medium green, ovate-oblong or obovate-oblong, and smooth along their margins. Each leaf tapers to a short petiole. There are separate male and female flowers on each plant (monoecious) at the axils of the leaves. These flowers are very small (less than 1/8" across) and greenish. Each male flower produces a single stamen, while each female flowers produces a single pistil with a pair of styles. These flowers have neither petals nor sepals. The blooming period occurs from late spring to mid-summer and lasts 1-2 months. The fruit of each female flower is 4-celled; it has a double-ovoid shape (similar to the fruit of a Galium sp.) and a short peduncle. Each cell of the fruit contains a single nutlet. This plant reproduces primarily by reseeding itself; it can reproduce vegetatively by forming rootlets at the axils of the leaves. Cultivation: The preference is light shade to dappled sunlight, moist to dry-mesic conditions, and barren soil that is devoid of competing ground vegetation. This plant is often found on compacted soil containing clay, glacial till, or rocky material. Range & Habitat: The native Terrestrial Starwort occurs occasionally in the southern half of Illinois; it is largely absent in the northern half of the state (see Distribution Map). Habitats include barren areas of hilly upland woodlands (particularly those that are dominated by oaks), edges of bluffs, footpaths in wooded areas, shaded gravelly seeps, and rocky riverbanks. Faunal Associations: Information about floral-faunal relationships for this species is unavailable.
Photographic Location: Along a bluff in Vermilion County, Illinois. Comments: This is probably the smallest terrestrial flowering plant in Illinois (Lemma minor, or Lesser Pondweed, is even smaller, but it floats on water). To see the flowers and fruits near the axils of the leaves, a 10x hand lens is required. Terrestrial Starwort resembles a low-growing moss, but it is more leafy in appearance. Other species in this genus are submerged or emergent aquatic plants; these Callitriche spp. are referred to as Water Starworts, and they are small in size as well. The submerged leaves of these latter species are linear in shape, but their emergent leaves resemble those of Terrestrial Starwort. While the fruits of Terrestrial Starwort have short peduncles, the fruits of Water Starworts are sessile, or nearly so.
0
0
文章
相关用户
举报 反馈

您有什么意见或建议,欢迎给我们留言。

请输入内容
设置
VIP
退出登录
分享

分享好文,绿手指(GFinger)养花助手见证你的成长。

请前往电脑端操作

请前往电脑端操作

转发
插入话题
提醒好友
发布
/
提交成功 提交失败 最大图片质量 成功 警告 啊哦! 出了点小问题 转发成功 举报 转发 显示更多 _zh 文章 求助 动态 刚刚 回复 邀你一起尬聊! 表情 添加图片 评论 仅支持 .JPG .JPEG .PNG .GIF 图片尺寸不得小于300*300px 最少上传一张图片 请输入内容