动态第348页 - 绿手指 - 养花技巧、花生病了怎么办、花园打理和设计

2018年02月13日

Description: This herbaceous perennial plant is about ½–1' tall. It has a loose tuft of basal leaves that emerge directly from the ground. They are green in the shade and often bluish or greyish green in the sun. These basal leaves are linear with parallel venation and up to 1/6" (4 mm.) across; they resemble short narrow Iris leaves. Among the leaves, there develops occasional flowering stalks with umbels of blue-violet flowers. These flowering stalks are usually more narrow than the leaves, but they are same height or slightly taller. Each stalk terminates in a long leaf-like bract, from which a spathe with a pair of short bracts will develop. This spathe may be sessile, or it may develop from a long secondary stalk (a peduncle). [图片]An umbel of flowers develops between the bracts of the spathe. Usually, only a few flowers in an umbel will be in bloom at the same time. Each flower is up to ½" (6 mm.) across; it consists of 3 petals and 3 sepals that appear nearly identical to each other. Each petal or sepal terminates in a tiny pointed tip that is often slightly notched on either side. There are fine lines of dark violet that lead to the center of the flower – these function as nectar guides. The base of each flower is bright yellow, from which there develops the sexual organs in the form of a bright yellow spike. At the base of each flower, there is a slender pedicel up to 1" long. There is no noticeable floral scent. The blooming period occurs during late spring or early summer, and lasts about a month. The globoid 3-celled seed capsules split into 3 sections, releasing small black seeds; these can be carried a short distance by gusts of wind. The root system is coarsely fibrous, and can form new offshoots. Cultivation: The preference is full or partial sun and moist to average conditions. Growth is best in a rich loam that is high in organic material. Light shade is also tolerated, but flowers will be fewer in number. The plants are fairly easy to grow under these conditions, and will gradually form larger clumps. Foliar disease doesn't appear to bother this and other species of blue-eyed grass. Flower on Secondary Stalk Range & Habitat: Stout Blue-Eyed Grass is widely distributed in Illinois, but it is less common or absent in many NW counties (see Distribution Map). This wildflower is native to Illinois. This plant can be found occasionally in moist to mesic black soil prairies, but it is more common in habitats with woody vegetation. These habitats include floodplain forests, thickets, woodland borders and openings, moist oak savannas, and the slopes of rivers. This plant usually occurs in grassy areas, as broad-leaved forbs tend to crowd it out. Faunal Associations: Halictine bees are probably the most important visitors of the flowers, where they collect pollen or suck nectar. Bumblebees, other kinds of bees, and bee flies are less frequent visitors seeking nectar, while Syrphid flies feed on pollen or suck nectar. The seeds and other parts of this plant are eaten to a limited extent by the Greater Prairie Chicken and Wild Turkey. Photographic Location: The photographs were taken at (or near) the webmaster's wildflower garden in Urbana, Illinois. Comments: This is a pretty plant while in bloom, and it has neat foliage. Distinguishing different species of Blue-Eyed grass can be rather difficult. Stout Blue-Eyed Grass has leaves that are slightly broader than most species of Blue-Eyed Grass, and it occasionally produces flowers from long secondary stalks, as shown in the lower photograph. The flowers are consistently deep blue-violet, rather than pale blue or white. Only a single spathe with an umbel of flowers is produced from a flowering stalk, while Sisyrinchium albidum (White Blue-Eyed Grass) produces two spathes. If you find a Blue-Eyed Grass with blue-violet flowers in a wooded area, this is the species that you are probably looking at. Other Sisyrinchium spp. in Illinois prefer sunnier habitats in either prairies or moist sandy meadows.

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Miss Chen

2018年02月13日

Description: This perennial plant is ½–1' tall, consisting of a tuft of basal leaves and flowering stalks that are grass-like in appearance. The basal leaves are shorter than the flowering stalks; they are both green, linear, and about 1/8" across. Each flowering stalk is narrowly winged and terminates in a pair of flower-bearing spathes and an outer leafy bract. Each spathe isClose-up of Flower sessile and consists of a pair of claw-like bracts up to 1" long; these bracts are often reddish or light brownish green. The outer leafy bract is up to 3" long. Between the bracts of each spathe, there develops a floppy umbel of flowers. Although an umbel has up to 6 flowers, only 1 or 2 flowers bloom at the same time. When it is fully open, each flower is about ½" across and consists of 6 white or pale blue tepals, a united column of yellow to orange-yellow stamens, and a green globoid ovary that is covered with fine glandular hairs. The slender pedicel of each flower is about ½" long. The blooming period occurs from late spring to early summer and lasts about 3-4 weeks; the flowers usually remain open from late morning to mid-afternoon on sunny days. There is no noticeable floral scent. Each flower is replaced by a seed capsule that is globoid and ridged; this capsule eventually turns brown and contains many small seeds. The root system consists of a tuft of coarse fibrous roots. This plant spreads by forming offsets and by reseeding itself. Cultivation: The preference is full sun, mesic levels of moisture, and a loamy soil, although this species will adapt to other growing conditions. It often adapts well to grassy areas, but dislikes competition from taller broad-leaved forbs. Range & Habitat: The native White Blue-Eyed Grass is occasional to locally common in most areas of Illinois; it is somewhat less common in the western half of the state (see Distribution Map). Habitats include mesic prairies, savannas, meadows in wooded areas, open woodlands, limestone glades, and grassy areas along railroads. This species can be found in degraded meadows with Kentucky Bluegrass, as well as higher quality prairies with native bunch grasses. Occasional wildfires are probably beneficial in preventing this species from becoming smothered by the decaying remains of taller vegetation. Faunal Associations: Various kinds of bees and flower flies visit the flowers for nectar or pollen; the bees are probably more effective at cross-pollination. I have observed a small dark beetle gnawing on the flowers; it remains unidentified. Little else is known about floral-faunal relationships for this species. [图片]Photographic Location: The webmaster's wildflower garden in Urbana, Illinois. In one photograph, a long leafy bract lies above the spathes. The bracts of the outer spathe are readily observable, while the bracts of the inner spathe are emerging from the leafy bract. Comments: This is one of the more common Sisyrinchium sp. in Illinois. White Blue-Eyed Grass can be rather variable in appearance: one common form is short (about 6" high) with white flowers, while another form is tall (about 12" high) with pale blue flowers. White Blue-Eyed Grass is the only Sisyrinchium sp. in Illinois with 2 sessile spathes at the apex of each flowering stalk. Only one of the spathes may be evident when a flowering stalk begins to bloom; however, both spathes (each consisting of a pair of claw-like bracts) should be observable later during the blooming period or when the seed capsules develop. Other Sisyrinchium spp. produce a single sessile spathe on each flowering stalk, or they produce spathes on long secondary stalks (peduncles) at least occasionally. Sometimes Sisyrinchium albidum is called Common Blue-Eyed Grass.

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Miss Chen

2018年02月13日

Description: This plant has a vase-like rosette of large basal leaves that are spade-shaped (cordate). Each leaf has a thick sandpapery texture, particularly on the underside, and is up to 18" long and 12" wide. On young leaves, the upper surface is relatively hairless and shiny, while older leaves become dull and rough. The lower surface is light green and pubescent. The leaf margins are coarsely serrated or dentate. The petioles are about 6" long, rather narrow and wiry, and light green or brown. The overall appearance is similar to a rhubarb plant, except the petioles are more slender. A naked flowering stalk emerges from the base of the plant, ranging in height from 3' to 10' in height. This stalk is green or red, and largely hairless. The upper part of the stalk divides gracefully into a panicle of yellow composite flowers and spherical green buds. Each compound flower is about 2-3" across, and consists of 15-30 ray florets with rather pointed tips surrounding numerous disk florets. There is no noticeable floral scent. The blooming period usually occurs from late summer to early fall, and lasts about a month for an individual plant. Prairie Dock usually blooms later than other Silphium spp. It has a stout taproot that can penetrate the soil to about 12' deep, and may form offsets only a short distance away from the mother plant. The rather light, flattened achenes can be carried several feet by the wind; they are without tufts of hair. [图片]Cultivation: The preference is full sun, a deep loamy soil, and moist to slightly dry conditions. Rocky or gravelly soil is tolerated. Drought tolerance is very good. Prairie Dock is rather slow to develop, but very reliable and nearly indestructible when mature. Patches of brown may develop when the leaves are damaged by drought, windstorms, or passing animals. It is a long-lived plant. Range & Habitat: The native Prairie Dock occurs in most of Illinois, except for a few counties in the south and NW (see Distribution Map). It is a common plant. Habitats include moist to dry black soil prairies, gravel prairies, shrub prairies, hill prairies, savannas, seeps, limestone glades, and prairie remnants along roadsides and railroads. The exceptional height of the flowering stalk is probably useful in keeping the flowers above the taller grasses, such as Andropogon gerardii (Big Bluestem). Recovery from occasional wildfires is very good. Panicles of Flowerheads Faunal Associations: The composite flowers attract long-tongued bees primarily, including honeybees, bumblebees, and Miner bees. Other flower visitors include Halictine bees, bee flies, and the Ruby-Throated Hummingbird. The grubs of Okanagana balli (Prairie Cicada) feed on the large taproot; this is an uncommon prairie insect that emerges during mid-summer. Both the larvae and adults of the Silphium Beetle (Rynchites sp.) feed on the flowerheads and stems of this and other Silphium spp. The larvae of Antistrophus rufus and Antistrophus minor (Gall Wasp spp.) feed on the flowering stem of Prairie Dock, forming invisible galls. The larvae of these species attract the hyperparasitic wasp Eurytoma lutea, whose larvae feed on these gall-formers. The larvae of Mordellistena aethiops (Tumbling Flower Beetle sp.) also feed within the stem, while the adults may feed on the flowerheads. The oligolectic Iowana frisoni (Aphid sp.) sucks juices from the flowering stem. Goldfinches eat the seeds, and may help to disperse them. Large mammalian herbivores, such as cattle and the American Bison, readily eat the foliage and stems of Prairie Dock; however, the coarse sandpapery leaves of mature plants are not attractive to the Cottontail Rabbit, which prefers vegetation that is shorter and more tender. [图片]Photographic Location: The photograph of the flowerhead close-up was taken at Meadowbrook Park in Urbana, the photograph of the panicles of flowerheads was taken along a railroad in Champaign, while the photograph of the basal leaves was taken at Dave Monk's postage stamp prairie in the latter city. Both Urbana and Champaign are in Illinois. Comments: This is a typical plant of mesic black soil prairies that competes successfully with tall prairie grasses. It has an impressive and unusual appearance, like something out of the Stone Age when Columbian mastodons and other megafauna inhabited the prairies of North America.

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Miss Chen

2018年02月13日

Description: This perennial plant is about 4-10' tall and remains unbranched, except for the panicle of flowering stems near the apex. The central stem is thick, hairless, and four-sided. The large opposite leaves are up to 8" long and 5" across, which join together around the central stem to form a cup that can hold water, hence the name of the plant. These leaves are broadly lanceolate to cordate, coarsely toothed, and have a rough, sandpapery texture. The yellow composite flowers bloom during early to mid-summer for about 1-1½ months. Each sunflower-like composite flower is about 3-4" across, consisting of numerous yellow disk florets that are surrounded by 18-40 yellow or pale yellow ray florets. The infertile disk florets protrude somewhat from the center and are rather conspicuous, while the ray florets are fertile. The latter produce thin achenes, each with a well-developed marginal wing, which are dispersed to some extent by the wind. The root system consists of a central taproot, and abundant shallow rhizomes that help to spread the plant vegetatively, often forming substantial colonies. [图片]Cultivation: The preference is full or partial sun, and moist loamy soil. This plant may drop some of its lower leaves in response to a drought. Sometimes, the leaves and buds of distressed plants turn brown, growth becomes stunted, and blossums abort in response to disease or drought. Another problem is that Cup Plant may topple over during a rainstorm with strong winds, particularly while it is blooming, or situated on a slope. Range & Habitat: The native Cup Plant occurs throughout Illinois, except for a few southern counties (see Distribution Map). It is fairly common. Typical habitats include moist black soil prairies, moist meadows near rivers, low-lying woodland edges and thickets, fens and seeps, lake borders, fence rows, and along ditches near railroads. [图片]Faunal Associations: Long-tongued bees, butterflies, and skippers are common visitors and the most important pollinators of the flowers. Some short-tongued bees, wasps, bee flies, and other kinds of flies also visit the flowers for pollen or nectar. The larvae of an Antistrophus sp. (Gall Wasp sp.) feed within the stems of this plant, and may attract the hyperparasitic wasp Eurytoma lutea. Various birds, especially goldfinches, are very fond of the seeds, and drink water from the cups formed by the leaves. Because of the tendency to form dense colonies, this plant provides good cover for birds, which often lurk among the leaves during the heat of the day, searching for insects or pausing to rest. Large herbivores, especially cattle, may eat the eat leaves of Cup Plant, especially those of immature plants. Photographic Location: The photographs of the flowering plants and perfoliate leaves were taken at a small restored prairie in Urbana, Illinois, while the photograph of the flowerhead close-up was taken at Meadowbrook Park in Urbana, Illinois. Comments: This is an imposing, but attractive plant when it is in bloom. Cup Plant is easy to distinguish from other Silphium spp., as well as various sunflowers, by the perfoliate leaves that can hold water, and the hairless four-angled stems.

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Miss Chen

2018年02月13日

Description: A mature specimen of this perennial plant ranges from 6-12' tall. The central stem is thick, light to medium green, and has conspicuous white hairs. There is some branching into flowering stems in the upper part of the plant. The basal leaves are 12-24" long and about half as wide. They are covered in fine white hairs, broadly lanceolate in overall shape, but deeply lobed or pinnatifid. The leaves become much smaller as they ascend up the stem. Flowering Stalks The inflorescence is very tall and elongated, with yellow composite flowers about 3-4" across. They resemble wild sunflowers in overall size, shape, and structure. However, like other Silphium spp., the small tubular disk florets are sterile, while the ray florets are fertile. There is little floral scent. A mature Compass Plant has 6-30 of these composite flowers, which bloom during mid-summer for about 1½ months. The seeds are large-sized, but flat and light, and can be carried several feet by the wind. A large central taproot can extend 15 ft. into the ground. A resinous substance is produced by the upper stem when the plant is blooming. This plant can live up to 100 years. Cultivation: The preference is full sun and moist to slightly dry conditions. A deep loamy soil is preferred for the central taproot. It takes several years for a seedling to develop into a full-sized mature plant. Mature plants are easy to maintain, resist drought, and can handle competition from other plants. If planted on a slope, there is a tendency to flop over, particularly while blooming. Range & Habitat: This is a typical plant of black soil prairies in the tallgrass region. It often co-occurs with Andropogon gerardii (Big Bluestem). Other habitats include sand prairies, savannas, glades, and areas along railroads. Compass Plant is fairly common throughout most of Illinois, except in the SE and scattered western counties, where it is uncommon or absent (see Distribution Map). This plant recovers from occasional fires readily. Compass Plant is native to Illinois. [图片]Faunal Associations: Long-tongued bees are the primary pollinators of the flowers, including bumblebees, Miner bees, large Leaf-Cutting bees, and others. Short-tongued Halictine bees and Syrphid flies also visit the flowers, but they are less effective at pollination. Occasionally, Sulfur butterflies and Monarchs may visit the flowers for nectar. Several species of insects are specialist feeders of Compass Plant. This includes the uncommon Okanagana balli (Prairie Cicada), whose grubs feed on the large taproot, while a Rynchites sp. (Silphium Beetle) and its larvae feed on the flower heads and stems. The larvae of Antistrophus rufus and Antistrophus minor (Gall Wasp spp.) feed within the stems, forming galls that are not visible from the outside. Nonetheless, they attract the hyperparasitic wasp Eurytoma lutea, whose larvae feed on these gall formers. Similarly, the larvae of Mordellistena aethiops (Tumbling Flower Beetle sp.) feed within the stems, while the adults may eat the flowers. The oligolectic aphid Iowana frisoni sucks the juices from the flowering stems. Photographic Location: The photographs of the flowering stalks and flowerheads were taken at the Lincoln Book Bindery in Urbana, Illinois, while the photograph of the lower leaves was taken at Meadowbrook Park in Urbana, Illinois. [图片]Comments: The common name derives from the belief by pioneers that the leaves of Compass Plant pointed in a north-south direction. While this is probably true more often than not, it is not always reliable. The resin was used by Indian children as a chewing gum. With its imposing heighth, interesting leaves, and abundant yellow flowers, Compass Plant is an extraordinary plant. No tallgrass prairie is complete without a sizeable population of them.

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Miss Chen

2018年02月12日

Description: This herbaceous perennial plant is 3-5' tall and unbranched, except near the inflorescence. The stout central stem is usually covered with stiff short hairs, but sometimes becomes glabrous with age. It is usually light green, but sometimes turns red in the presence of bright sunlight. The opposite leaves are up to 5" long and 2½" wide. They are broadly lanceolate to ovate, and have stiff small hairs on both the upper and lower sides, providing a sandpapery texture. The margins of these leaves are usually smooth, or they may have tiny teeth. As they ascend the stem, the opposite leaves rotate their direction by 90°. A panicle of composite yellow flowers appear at the top of the plant, resembling small sunflowers. Each flower is about 2–3" across, consisting of numerous disk florets surrounded by 12-25 ray florets. Only the ray florets are fertile. There is no noticeable floral scent. Often, there are side stems that bear smaller panicles of flowers. The blooming period occurs from mid-summer to fall, and lasts about 1-2 months. The seeds are large, flat, and lightweight – they can be carried several feet by the wind. The root system consists of a taproot and short rhizomes, which enable this plant to form clumps. Several varieties of this plant have been reported by various authorities, some of which may be natural hybrids with other Silphium spp. Cultivation: The preference is full sun and mesic to dry conditions. The soil can contain loam, clay-loam, or some gravel. Rosinweed is rarely bothered by disease and is easy to grow. It matures more quickly than many other members of the genus, such as Silphium terebinthinaceum (Prairie Dock) and Silphium laciniatum (Compass Plant). Another nice feature of this plant is that it rarely flops over in the flower garden, if the location isn't on a steep slope. [图片]Range & Habitat: The native Rosinweed occurs throughout most of Illinois, except for a few southern and western counties (see Distribution Map). It is a fairly common plant. Habitats include mesic to dry black soil prairies, gravel prairies, clay prairies, hill prairies, openings in rocky upland forests, limestone glades, and areas along railroads, particularly where prairie remnants occur. This plant can survive significant degradation, and recovers readily from occasional wildfires. It competes well against most prairie grasses and forbs in mesic to dry areas. Faunal Associations: The pollen and nectar of the flowers attract long-tongued bees primarily, including honeybees, bumblebees, Little Carpenter bees, Epeoline Cuckoo bees, Miner bees, and large Leaf-Cutting bees. Insects rarely attack this plant, although the Silphium Beetle (Rhynchites sp.) may feed on the flowers and seeds, and the caterpillars of the rare Tabenna silphiella (Silphium Moth) eat the epidermis of the leaves. The larvae of a Gall Wasp (Antistrophus sp.) may feed within the stems, forming galls that are invisible from the outside. They attract the hyperparasitic wasp Eurytoma lutea, whose larvae feed on the larvae of the Gall Wasp. Some butterflies occasionally visit the flowers, including Sulfurs and Painted Ladies. Other visitors include short-tongued bees and various flies. The seeds are eaten occasionally by Goldfinches. Small herbivores, such as rabbits, are less likely to eat this plant because of its height and the coarseness of its leaves. However, some large herbivores, such as cattle, readily consume the foliage, stems, and flowers. Photographic Location: The photographs were taken at Meadowbrook Park in Urbana, Illinois. Comments: Like other Silphium spp., Rosinweed has a fragrant resin while in flower, which was chewed as gum by Amerindian children. It is less dramatic in appearance than some of its gigantic cousins, but matures more quickly and tolerates drought as well or better. Rosinweed resembles many Helianthus spp. (Sunflowers), but its disk florets are sterile and ray florets are fertile. The Sunflowers, on the other hand, have fertile disk florets and sterile ray florets. Rosinweed tends to produce flowers earlier than the Sunflowers, but sometimes their blooming periods overlap. While this plant can form sizable clumps, it doesn't spread as aggressively by means of underground rhizomes as many Sunflower species, nor is it known to be allelopathic.

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Miss Chen

2018年02月12日

Description: This herbaceous perennial plant is 2-3' tall and unbranched, except for the upper flowering stems. The stems are covered with fine white hairs, as are the leaves, on both the upper and lower sides. These leaves are up to 4" long and 2" wide, light to medium green, lanceolate to ovate, with a fuzzy texture and smooth edges. They occur in opposite pairs, rotating 90° degrees as they ascend the stem. Small clusters of bright red or scarlet flowers occur at the top of the plant. The star-shaped flowers have 5 narrow petals that flare abruptly outward from a long tubular calyx that is about 1" long. The flowers are about ¾–1" across, and have exerted stamens with grey anthers. The calyx is light green, longitudinally ridged, and covered with sticky hairs that trap climbing insects. The blooming period occurs from mid- to late summer and lasts about a month. There is no floral scent. The small black seeds usually fall only a short distance from the mother plant. The root system consists of a taproot. [图片]Cultivation: The preference is full or partial sun in moist to slightly dry soil. The soil can contain significant amounts of loam, clay-loam, or rocky material. Royal Catchfly is fairly easy to grow, but it is somewhat slower to develop than other plants and resents excessive shading. During drought, the lower leaves may turn yellow and fall off the plant. Plants begin to bloom while small in size, but it takes several years to reach their full potential. Range & Habitat: The native Royal Catchfly occurs in widely scattered counties in Illinois, primarily in areas near Chicago, East St. Louis, and some SE counties (see Distribution Map). It is a rare plant that has endangered status in Illinois. Habitats include mesic black soil prairies, openings in upland forests, savannas, scrubby barrens, and open areas along roadsides and railroads. Because this forb is showy and available through the nursery trade, it has been introduced elsewhere around the state in prairie restorations and flower gardens. [图片]Faunal Associations: The nectar of the flowers attracts the larger butterflies, such as Papilio polyxenes asterias (Black Swallowtail), and the Ruby-Throated Hummingbird. Aphids suck juices from the upper stems occasionally. There is little or no information regarding this plant's relationships to birds and animals at the present time. Photographic Location: The photograph was taken at the webmaster's wildflower garden in Urbana, Illinois. Comments: Red is an uncommon color among prairie plants because many pollinating insects (e.g., bees) are insensitive to this range of the light spectrum. However, some butterflies perceive red, and for this reason are attracted to such flowers. The flowers of Royal Catchfly have a design that favors butterflies as pollinating agents: They have a proboscis that is sufficiently long to reach the nectar at the bottom of the long narrow tube that is formed by the calyx, while the flared petals provide a colorful landing platform for their legs. The only other plant that resembles Royal Catchfly in Illinois is Silene virginica (Fire Pink). This latter species also has bright red flowers, but the tips of its petals are slightly notched. Fire Pink is a shorter plant that occurs in and around woodland areas, often on clay or rocky banks, and is not found in prairies.

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Miss Chen

2018年02月12日

Description: This annual plant is about ½–1½' tall. It has stems that are unbranched or sparingly branched below, becoming more branched above; they are ascending to erect. The stems are light green, terete, slender, and glabrous to minutely pubescent. In addition, there are usually sticky patches along the stems between adjacent pairs of leaves; these sticky patches are often discolored and they may have dead insects, spider webs, and other debris clinging to them. The nodes of the stems, where pairs of leaves occur, are somewhat swollen and enveloped by short sheaths with membranous upper margins. Opposite leaves are sparsely distributed along the entire length of each stem, where they are sessile. These leaves are up to 2" long and 10 mm. across, although they are usually about one-half that size. The leaves are linear-lanceolate or linear-elliptic in shape, while their margins are entire (toothless) and minutely ciliate. The upper and lower surfaces of leaves are light green or light-medium green; they are glabrous to sparsely and minutely pubescent, except at their bases, where some white hairs occur. The leaves usually have conspicuous central veins, along which they are either flat or angled slightly upward. The upper stems terminate in small clusters of flowers (one floral cluster per stem); each floral cluster has relatively few flowers (typically only 2-4). The pedicels are up to 12 mm. (½" long), light green, terete, and slender. Flowering Plant with Dead Flying Insect Each flower is about 4-5 mm. across, consisting of an open-ovoid calyx with 6 teeth, 5 small petals, 10 stamens, and a pistil with 3 styles. The petals are usually white, although sometimes they are pink or purple to a greater or lesser degree. Some plants produce bicolored petals that are white above and purple below, while other plants produce flowers that lack petals. These petals are obovate in shape and notched at their tips. A mature calyx is about 6-9 mm. long and about one-half as much across. Each calyx has 10 longitudinal ribs that are slightly elevated, angular-convex, and relatively thick; they are separated by narrow shallow furrows. The ribs of the calyx are often a slightly darker shade of green than the furrows; the calyx overall is light-medium green, glabrous, and sticky. The blooming period occurs from late spring to mid-summer, lasting about 1 month for a colony of plants. However, some plants may bloom later in the year in response to disturbance. The flowers are diurnal, opening up in response to bright sunlight. There is no noticeable floral scent. Mature seeds are less than 1 mm. in length, reniform (kidney-shaped), minutely bumpy across their surfaces, and black; they are distributed to some extent by the wind. The root system consists of a branching taproot. Reproduction is entirely by seeds. [图片]Cultivation: The preference is full sun and rather dry conditions. Poor gravelly, cindery, or sandy soil is preferred, as this reduces competition from other plants. In open situations with exposed topsoil, this plant can reseed itself readily, becoming rather weedy. Range & Habitat: Sleepy Catchfly occurs in most counties of Illinois, where it is widely distributed and native (see Distribution Map). Depending on the area, this plant is occasional to common. Habitats include gravel prairies, hill prairies, dry sand prairies, rocky glades, thinly wooded bluffs, pastures in upland areas, abandoned fields, areas along railroads, and roadsides. Sleepy Catchfly is more common in habitats that have been subjected to occasional wildfires, or that have been disturbed by human activities. [图片]Faunal Associations: Primarily flies and small bees visit the flowers for nectar or pollen. Flies and other small insects can become stuck on the sticky surface of the calyx, while ants can become stuck on the sticky patches of stems. Sleepy Catchfly is not able to absorb nutrients from these trapped insects, however, in the manner of a carnivorous plant. An aphid, Aphis sambuci (Elder Aphid), uses Silene spp. as summer host plants, feeding on the sap of their roots. There are also two tortoise beetles, Cassida flaveola (Pale Tortoise Beetle) and Cassida azurea (Neon Tortoise Beetle), that have been introduced into North America to control such Eurasian weeds as Silene vulgaris (Bladder Campion) and Silene pratensis (White Campion). It is possible that these tortoise beetles may feed on some native Silene spp. in open weedy areas, although this has not been demonstrated for Sleepy Catchfly. Photographic Location: The photographs were taken near an abandoned railroad in Urbana, Illinois, on black cindery ground. [图片]Comments: Sleepy Catchfly is a highly variable plant that is easily overlooked, except where it occurs in substantial colonies and happens to be in bloom. The plant in the photographs is a form of Sleepy Catchfly with bicolored flowers, Silene antirrhina bicolor, which is supposed to be uncommon. Plants that produce flowers without petals are referred to as Silene antirrhina apetala, while plants without sticky patches on their stems are referred to as Silene antirrhina deaneana; see Mohlenbrock (2001) for a short discussion of these forms. Prior to flowering, Sleepy Catchfly resembles some species of chickweed (Stellaria spp.) with grass-like leaves. However, Sleepy Catchfly can be distinguished from these species by the sticky patches on its stems. In addition, the flowers of Sleepy Catchfly differ from those of chickweeds by having larger bladder-shaped calyces, as described above. There are also non-native Silene spp. that resemble Sleepy Catchfly to some extent (e.g., Silene conica, Silene dichotoma, and Silene gallica). These species also lack sticky patches on their stems, and their flowers can differ in such characteristics as the number of styles, the number of stamens, the number of ribs or veins along the sides of their calyces, the number of teeth along the upper rims of their calyces, and the presence of hairs or bristles along the sides of their calyces.

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Miss Chen

2018年02月12日

Description: This perennial wildflower is woody at the base and only 4-10" tall. The lower stems have shredded bark that is grey-brown, while the upper stems are non-woody and light green to red. Most branching occurs toward the base of each plant; the stems have a tendency to sprawl across the ground as they become longer. Alternate trifoliate leaves develop primarily from the base of each stem. Individual leaflets are up to 1½" long and ½" across; the middle leaflet is usually longer than the 2 lateral leaflets. The shape of each leaflet is oblanceolate, terminating in a truncate tip with 3 large teeth. The leaflets are evergreen with a somewhat thick leathery texture; their upper surfaces are medium to dark green and shiny, while their lower surfaces are pale green and often slightly pubescent. During the winter, the leaflets often become tinted with red. Each trifoliate leaf has a long petiole up to 2" long; this petiole is light green to red and it has a pair of large linear-lanceolate stipules at its base. Some of the upper stems terminate in cymes or compound cymes of 1-12 flowers. Each flower is up to ½" across, consisting of 5 white petals, a light green calyx with 5 ovate teeth, a dense cluster of pistils, and 20-30 stamens. Adjacent to the calyx of the flower, there are 5 light green bracteoles (tiny bracts); these bracteoles are linear-oblong and shorter than the teeth of the calyx. The slender white styles of the pistils spread laterally from the center of the flower. The branches of each cyme are terete, light green, and often pubescent. At the base of each fork in the cyme, there is a pair of small lanceolate bracts. [图片]The blooming period occurs during the summer and lasts about 2-3 months. At maturity, each flower produces a cluster of hairy brown achenes. The root system is woody and can produce vegetative offsets from underground runners. Older plants may produce a caudex. Cultivation: The preference is plenty of sun, dry conditions, and well-drained soil that is rocky, gravelly, or sandy. This plant can adapt to a rock garden if it is sunny and well-drained. Because this is a boreal species, it dislikes excessive heat during the summer. Range & Habitat: In Illinois, Three-Toothed Cinquefoil has been found only in Cook County (see Distribution Map), where it was probably native. Because this species has not been observed in any natural area of the state since 1895, it is probably extirpated within the state. The habitat of Three-Toothed Cinquefoil in Illinois was a gravel hill prairie. Outside of the state, it is found on treeless mountain tops and other upland rocky areas that are sunny; it also occurs along sandy banks. The range of this species extends from the upper Great Lakes to New England, and then northward to the Arctic Circle of Canada and Greenland. Small isolated populations still occur in the Appalachian Mountains as far south as northern Georgia. Faunal Associations: Because this species is quite rare in Illinois and the surrounding area, information about floral-faunal relationships is unavailable. Like similar Potentilla spp. (Cinquefoil species), the flowers probably attract small bees and Syrphid flies. Photographic Location: A rock garden at the Arboretum of the University of Illinois in Urbana, Illinois. Comments: Another scientific name of this species is Potentilla tridentata. Three-Toothed Cinquefoil was reclassified into its own genus as a result of genetic analysis, which revealed that it was more closely related to another boreal species, Sibbaldia procumbens (Sibbaldia). The trifoliate leaves of this latter species are similar to those of Three-Toothed Cinquefoil, but the flowers of Sibbaldia are less showy because of the small size of the petals. Three-Toothed Cinquefoil differs from Potentilla spp. by the lateral styles of its flowers; it also differs from many of these species by its woody lower stems and evergreen leaves.

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Miss Chen

2018年02月12日

Description: This annual plant is 1-2½' tall, branching occasionally. The stems are light green and somewhat ridged. The lower stems often sprawl along the ground in open areas, otherwise this plant is erect. The compound leaves alternate along the stems. They are evenly pinnate, usually with 3 pairs of leaflets, and have long leaf stems (primary petioles). The obovate leaflets are individually 1½" long and 1" across. They are devoid of hairs and pale green on their undersides. There is an extra-floral nectary close to the lowest pair of leaflets on the upper side of each compound leaf. This nectary resembles a small brown spike. The foliage has a slightly rank odor. One or two flowers develop from the upper axils of the compound leaves. These flowers have pedicels about 1" long and tend to nod slightly downward. They are about 1" across, and consist of 5 rounded yellow petals and 10 stamens; the petals are often slightly unequal in size. The flowers are subtended by a light green calyx that is divided into 5 folded sepals; these sepals are shorter than the petals and hairless. In Illinois, the blooming period occurs from late summer through the fall, and lasts about 1-2 months. There is no floral scent. A long seedpod develops from each flower that is 4-6" long, but only 1/3" across. This seedpod curves downward and resembles a sickle in its overall shape. The root system consists of taproot. This plant spreads by reseeding itself. Cultivation: The preference is full sun and moist to slightly dry conditions. This plant tolerates different kinds of soil, from fertile loam to gravelly soil; in fact, it often thrives in railroad ballast. Drought tolerance is good, and the foliage is rarely bothered by foliar disease. It is somewhat slow to develop for an annual plant, and tends to bloom late in the year in Illinois. [图片]Range & Habitat: Sicklepod has been reported from only a few counties in southern Illinois and in the Chicago area; it has been observed recently along a railroad track in Champaign County, where it is probably adventive from the south (see Distribution Map). This is a rare plant in Illinois, although it is more common in many south-central and southeastern states of the US; it also occurs in the American tropics. In southern Illinois, Sicklepod may be native, while elsewhere in the state it is definitely adventive from the south. Habitat information is scanty, but it has been observed in moist meadows along rivers, open areas along railroads, and in waste areas. Areas with a history of disturbance are preferred. Faunal Associations: The extra-floral nectaries attract ants primarily; they may also attract some wasps, flies, or small bees. The pollen of the flowers attract long-tongued bees, such as bumblebees, Miner bees, and large Leaf-Cutting bees. The caterpillars of several species of Sulfur butterflies are known to feed on the foliage of Cassia spp., including Eurema lisa (Little Sulfur), Eurema nicippe (Sleepy Orange), and Phoebis sennae cubule (Cloudless Sulfur). Some upland gamebirds occasionally eat the seeds of Senna spp., especially the Bobwhite and Greater Prairie Chicken. Mammalian herbivores are unlikely to utilize this plant as a food source to any significant extent because of the unpleasant taste and toxic nature of the foliage, which has been found capable of poisoning livestock. [图片]Photographic Location: Photographs were taken along a railroad in Savoy, Illinois. Comments: This rare plant has attractive foliage, but blooms sparingly. Sicklepod resembles Senna marilandica (Maryland Senna) and Senna hebecarpa (Wild Senna) somewhat in appearance, but it is a shorter annual plant that has 1) fewer leaflets per compound leaf, 2) leaflets with a more obovate shape, and 3) seedpods that are more curved and slender. In the past, Sicklepod was assigned to the Bean family (Fabaceae), rather than the Caesalpinia family.

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