文章
Miss Chen
2018年08月09日
Description: This plant is a perennial in areas with mild winters, otherwise it is an annual. It is about 2-4' tall and branches frequently. The smooth stems are greyish green and finely pubescent (canescent). The alternate leaves are up to 6" long and 4" across. They are ovate or cordate-ovate, smooth or slightly undulate along the margins, and finely pubescent on the underside (young leaves are finely pubescent on on the upperside as well). Each leaf is usually asymmetric at the base (oblique).
Individual flowers develop on short pedicels where the upper stems branch dichotomously. Each white flower is about 5-7" long and 3-4" across. The corolla has 5 shallow lobes that are barely perceptible; there is a short point between each pair of lobes along the rim of the corolla. Five white stamens are exerted from the center of the corolla. The base of the flower consists of a tubular calyx that has 5 broad teeth along its upper rim; this calyx extends to about ½ the length of the flower, and it lacks conspicuous ridges or wings. The blooming period occurs from mid-summer to fall and lasts about 1-2 months. The flowers often bloom during the day. Each flower is replaced by a prickly seed capsule about 1" across. Each capsule contains several seeds that are large and angular. The root system consists of a taproot. This plant reproduces by reseeding itself.
Cultivation: The preference is full sun, mesic conditions, and fertile loamy soil, preferably at a site that is not too windy. Flea beetles and other insects may chew tiny holes in the leaves.
Range & Habitat: Angel's Trumpet has naturalized in scattered counties across Illinois, although it rarely persists (see Distribution Map). Habitats include areas adjacent to gardens, areas along roads and railroads, and waste areas. This plant is occasionally cultivated in flower gardens, from which it occasionally escapes. Angel's Trumpet was introduced from central America and/or southwestern United States.
Faunal Associations: Little is known about floral-faunal relations for this species. The flowers are pollinated by hummingbirds and Sphinx moths. The foliage contains stramonium (a narcotic) and probably other toxic chemicals, therefore it is unlikely to be bothered by deer and other mammalian herbivores.
Photographic Location: An herb garden at Meadowbrook Park in Urbana, Illinois.
Comments: The flowers are extremely large and showy. The only other member of this genus that has naturalized in Illinois is Datura stramonium (Jimsonweed), which is common and weedy. Like Angel's Trumpet, Jimsonweed is a bushy herbaceous plant with large leaves and funnelform flowers. However, the flowers of Jimsonweed are smaller and less showy (up to 5" long and 2½" across), and they are less likely to bloom during the day. The foliage of Jimsonweed is largely hairless, while Angel's Trumpet has stems and leaf undersides that are finely pubescent. The leaf margins of Jimsonweed are lobed or undulate, while the leaf margins of Angel's Trumpet are smooth or slightly undulate. Another scientific name for Angel's Trumpet is Datura inoxia. Another common name for this species is Ghost Flower.
Individual flowers develop on short pedicels where the upper stems branch dichotomously. Each white flower is about 5-7" long and 3-4" across. The corolla has 5 shallow lobes that are barely perceptible; there is a short point between each pair of lobes along the rim of the corolla. Five white stamens are exerted from the center of the corolla. The base of the flower consists of a tubular calyx that has 5 broad teeth along its upper rim; this calyx extends to about ½ the length of the flower, and it lacks conspicuous ridges or wings. The blooming period occurs from mid-summer to fall and lasts about 1-2 months. The flowers often bloom during the day. Each flower is replaced by a prickly seed capsule about 1" across. Each capsule contains several seeds that are large and angular. The root system consists of a taproot. This plant reproduces by reseeding itself.
Cultivation: The preference is full sun, mesic conditions, and fertile loamy soil, preferably at a site that is not too windy. Flea beetles and other insects may chew tiny holes in the leaves.
Range & Habitat: Angel's Trumpet has naturalized in scattered counties across Illinois, although it rarely persists (see Distribution Map). Habitats include areas adjacent to gardens, areas along roads and railroads, and waste areas. This plant is occasionally cultivated in flower gardens, from which it occasionally escapes. Angel's Trumpet was introduced from central America and/or southwestern United States.
Faunal Associations: Little is known about floral-faunal relations for this species. The flowers are pollinated by hummingbirds and Sphinx moths. The foliage contains stramonium (a narcotic) and probably other toxic chemicals, therefore it is unlikely to be bothered by deer and other mammalian herbivores.
Photographic Location: An herb garden at Meadowbrook Park in Urbana, Illinois.
Comments: The flowers are extremely large and showy. The only other member of this genus that has naturalized in Illinois is Datura stramonium (Jimsonweed), which is common and weedy. Like Angel's Trumpet, Jimsonweed is a bushy herbaceous plant with large leaves and funnelform flowers. However, the flowers of Jimsonweed are smaller and less showy (up to 5" long and 2½" across), and they are less likely to bloom during the day. The foliage of Jimsonweed is largely hairless, while Angel's Trumpet has stems and leaf undersides that are finely pubescent. The leaf margins of Jimsonweed are lobed or undulate, while the leaf margins of Angel's Trumpet are smooth or slightly undulate. Another scientific name for Angel's Trumpet is Datura inoxia. Another common name for this species is Ghost Flower.
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文章
Miss Chen
2018年08月09日
Description: This plant is a summer annual about 3-5' tall that branches dichotomously. The stems are green or purple and largely hairless, although young stems often have conspicuous hairs. The alternate leaves are up to 8" long and 6" across (excluding the petioles). They are ovate or ovate-cordate in outline, but pinnately lobed. These lobes are somewhat shallow and pointed at their tips; there are usually 2-3 of these lobes on each side of the leaf blade. The margin of each leaf may have a few secondary lobes or coarse dentate teeth, otherwise it is smooth or slightly undulate. The leaves may be slightly pubescent when young, but become hairless with age; the upper surface of each leaf is often dark green and dull. The foliage of Jimsonweed exudes a bitter rank odor.
Individual flowers occur where the stems branch dichotomously; the upper stems also terminate in individual flowers. The funnelform corolla of each flower is up to 5" long and 2" across when fully open; its outer rim has 5 shallow lobes. Each of these lobes forms an acute point in the middle.The corolla is white or pale violet throughout, except at the throat of the flower, where thick veins of dark violet occur. The light green calyx is shorter than the corolla and conspicuously divided along its length by 5 membranous wings. The blooming period occurs from mid-summer to early fall and lasts about 2 months. The flowers usually don't open up until midnight and close early in the morning; less often, the flowers may bloom toward the middle of the day, especially when it is cloudy. Individual flowers last only a single day. Each flower is replaced by a hard fruit that is dry and spiny; it is about 1½" long, 1" across, and spheroid-ovoid in shape. Underneath each fruit is a truncated remnant of the calyx that curves sharply downward. These fruits are initially green, but become brown with maturity; they divide into 4 segments to release the seeds. The large seeds are dull, irregular, and dark-colored; their surface may be pitted or slightly reticulated. The root system consists of taproot that is shallow for the size of the plant; it branches frequently. Jimsonweed spreads by reseeding itself.
Cultivation: The preference is full or partial sun, moist to mesic conditions, and a rich fertile soil with high nitrogen content. This type of soil is necessary to supply the nutrients that are required by the prodigious growth of this annual plant. The foliage is often pitted by tiny holes that are made by flea beetles (the same or similar species that attack eggplant). The seeds can remain viable in the ground for several years.
Range & Habitat: Jimsonweed is a fairly common plant that has been observed in most counties of Illinois (see Distribution Map). It is probably adventive from tropical America and it was first observed in the United States at the Jamestown colony during the 17th century. Typical habitats include cropland (particularly corn fields), fallow fields, old feed lots, piles of soil at construction sites, mounds of decomposed mulch and discarded vegetation, urban vacant lots, and miscellaneous waste areas. Disturbed areas with open fertile soil are strongly preferred.
Faunal Associations: The flowers are cross-pollinated by nectar-seeking Sphinx moths. Various species of beetles are attracted by the flowers, especially at night, where they steal nectar and chomp on the pollen. The foliage and other parts of Jimsonweed are a source of food for several flea beetles (Epitrix spp.), Three-lined Potato Beetle (Lema daturaphila), Colorado Potato Beetle (Leptinotarsa decemlineata), Clavate Tortoise Beetle (Plagiometriona clavata), and larvae of the Pink-spotted Hawk Moth (Agrius cingulata); see Clark et al. (2004) and Covell (1984/2005). The foliage and seeds contain an impressive assortment of toxic alkaloids that can be fatal to mammalian herbivores and humans. Some of these alkaloids are mildly narcotic and hallucinogenic. The immature seeds are especially poisonous; as few as 20 seeds can fatally poison a child. It is doubtful that birds make any use of these toxic seeds. Humans help to spread the seeds around through activities that are related to agriculture, construction, and landscaping.
Photographic Location: Near piles of soil at a vacant lot in Champaign, Illinois. These piles of soil were dumped and occasionally carried off by trucks in relation to off-site construction and landscaping activities.
Comments: The common name 'Jimsonweed' is probably a corruption of 'Jamestown Weed,' referring to where this species was first observed in North America. Another common name that is often used for this species is 'Thornapple.' Two varieties of Jimsonweed have been described. The typical variety has green stems and white flowers, while var. tatula has purple stems and either pale violet or purple-striped flowers. Jimsonweed has a distinct appearance, making it easy to identify.
The only other Datura spp. in Illinois, Datura wrightii (Angel's Trumpet), rarely naturalizes in the wild. It is sometimes cultivated in flower gardens because of its attractive flowers. Angel's Trumpet is a hairier plant with unlobed leaves and larger flowers. The corolla of its flowers ranges from 5-8" in length, while the corolla of Jimsonweed's flowers is about 3–5" in length. Both of these Datura spp. have flowers that bloom during the night. Another species in the Nightshade family, Nicandra physalodes (Shoofly Plant), also rarely naturalizes in the wild. The Shoofly Plant has foliage that is similar to Jimsonweed, but its funnelform flowers are much smaller (less than 1½" long and across). Unlike Jimsonweed, the flowers of Shoofly Plant are strictly diurnal.
Individual flowers occur where the stems branch dichotomously; the upper stems also terminate in individual flowers. The funnelform corolla of each flower is up to 5" long and 2" across when fully open; its outer rim has 5 shallow lobes. Each of these lobes forms an acute point in the middle.The corolla is white or pale violet throughout, except at the throat of the flower, where thick veins of dark violet occur. The light green calyx is shorter than the corolla and conspicuously divided along its length by 5 membranous wings. The blooming period occurs from mid-summer to early fall and lasts about 2 months. The flowers usually don't open up until midnight and close early in the morning; less often, the flowers may bloom toward the middle of the day, especially when it is cloudy. Individual flowers last only a single day. Each flower is replaced by a hard fruit that is dry and spiny; it is about 1½" long, 1" across, and spheroid-ovoid in shape. Underneath each fruit is a truncated remnant of the calyx that curves sharply downward. These fruits are initially green, but become brown with maturity; they divide into 4 segments to release the seeds. The large seeds are dull, irregular, and dark-colored; their surface may be pitted or slightly reticulated. The root system consists of taproot that is shallow for the size of the plant; it branches frequently. Jimsonweed spreads by reseeding itself.
Cultivation: The preference is full or partial sun, moist to mesic conditions, and a rich fertile soil with high nitrogen content. This type of soil is necessary to supply the nutrients that are required by the prodigious growth of this annual plant. The foliage is often pitted by tiny holes that are made by flea beetles (the same or similar species that attack eggplant). The seeds can remain viable in the ground for several years.
Range & Habitat: Jimsonweed is a fairly common plant that has been observed in most counties of Illinois (see Distribution Map). It is probably adventive from tropical America and it was first observed in the United States at the Jamestown colony during the 17th century. Typical habitats include cropland (particularly corn fields), fallow fields, old feed lots, piles of soil at construction sites, mounds of decomposed mulch and discarded vegetation, urban vacant lots, and miscellaneous waste areas. Disturbed areas with open fertile soil are strongly preferred.
Faunal Associations: The flowers are cross-pollinated by nectar-seeking Sphinx moths. Various species of beetles are attracted by the flowers, especially at night, where they steal nectar and chomp on the pollen. The foliage and other parts of Jimsonweed are a source of food for several flea beetles (Epitrix spp.), Three-lined Potato Beetle (Lema daturaphila), Colorado Potato Beetle (Leptinotarsa decemlineata), Clavate Tortoise Beetle (Plagiometriona clavata), and larvae of the Pink-spotted Hawk Moth (Agrius cingulata); see Clark et al. (2004) and Covell (1984/2005). The foliage and seeds contain an impressive assortment of toxic alkaloids that can be fatal to mammalian herbivores and humans. Some of these alkaloids are mildly narcotic and hallucinogenic. The immature seeds are especially poisonous; as few as 20 seeds can fatally poison a child. It is doubtful that birds make any use of these toxic seeds. Humans help to spread the seeds around through activities that are related to agriculture, construction, and landscaping.
Photographic Location: Near piles of soil at a vacant lot in Champaign, Illinois. These piles of soil were dumped and occasionally carried off by trucks in relation to off-site construction and landscaping activities.
Comments: The common name 'Jimsonweed' is probably a corruption of 'Jamestown Weed,' referring to where this species was first observed in North America. Another common name that is often used for this species is 'Thornapple.' Two varieties of Jimsonweed have been described. The typical variety has green stems and white flowers, while var. tatula has purple stems and either pale violet or purple-striped flowers. Jimsonweed has a distinct appearance, making it easy to identify.
The only other Datura spp. in Illinois, Datura wrightii (Angel's Trumpet), rarely naturalizes in the wild. It is sometimes cultivated in flower gardens because of its attractive flowers. Angel's Trumpet is a hairier plant with unlobed leaves and larger flowers. The corolla of its flowers ranges from 5-8" in length, while the corolla of Jimsonweed's flowers is about 3–5" in length. Both of these Datura spp. have flowers that bloom during the night. Another species in the Nightshade family, Nicandra physalodes (Shoofly Plant), also rarely naturalizes in the wild. The Shoofly Plant has foliage that is similar to Jimsonweed, but its funnelform flowers are much smaller (less than 1½" long and across). Unlike Jimsonweed, the flowers of Shoofly Plant are strictly diurnal.
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文章
Miss Chen
2018年08月09日
Description: This herbaceous plant is a winter or summer annual about 4-18" tall and similarly across; it branches dichotomously. Initially, a few basal leaves develop during the autumn or spring, but during late spring this plant bolts The stems of bolting plants are medium green, terete, and glabrous. Alternate leaves occur along the entire length of these stems, becoming smaller in size as they ascend. They vary in size from ½–3½" long and similarly across. The leaves are medium green, glabrous, and bipinnatifid or tripinnatifid in structure; they branch dichotomously and somewhat irregularly, forming narrowly linear to filiform lobes. These lobes are up to ¾" (20 mm.) long and about 0.5–1 mm. across. The narrow petioles of the leaves are nearly zero to 2" long; they are mostly green and glabrous, although the bases of these petioles have sheaths with white- to brown-membranous margins.
Both axillary and terminal umbels of flowers are produced in abundance. These umbels are usually compound, consisting of 2-3 umbellets (rarely with 4 umbellets), although sometimes they are simple. The compound umbels span about ¾–1¼" (20-32 mm.) across; their peduncles (basal stalks) are ¼–1" (6-24 mm.) long. The rays (basal stalklets) of the umbellets are ascending and divergent; they are ¼–¾" (6-20 mm.) in length. Individual umbellets span ¼–½" (6-12 mm.) across, consisting of 5-15 flowers; their pedicels are nearly zero to ¼" long. The peduncles, rays, and pedicels of each compound umbel are medium green, glabrous, and straight. Both the umbels and umbellets lack floral bracts. Individual flowers are only 1-2 mm. across when they are fully open. Each flower consists of 5 white petals, a toothless green calyx, 5 stamens, and a 2-celled ovary with a pair of short styles. The blooming period occurs during the summer and autumn, lasting about 2-3 months. Only a few flowers are in bloom at the same time.
Afterwards, the flowers are replaced by dry fruits (schizocarps); immature fruits are light green, while mature fruits turn brown; the latter soon fall to the ground. Each schizocarp consists of 2 hairless seeds. Individual seeds are 1.0–1.5 mm. long and asymmetrically ellipsoid in shape; one side of each seed is flat to slightly concave, while the other side is convex and conspicuously ribbed (3 ribs that are separated by 2 furrows). The root system consists of a slender taproot. This plant reproduces by reseeding itself.
Cultivation: The preference is full sun and moist conditions; a variety of soil types are tolerated. This plant will colonize drier ground, but it is vulnerable to hot dry weather. In some situations, this plant can spread aggressively, although this has not been a problem (thus far) in Illinois.
Range & Habitat: The non-native Fir-leaved Celery is a rare weed in Illinois. So far, it has occurred only in Champaign County (see Distribution Map). It is probably native to subtropical areas of Central and South America. However, it has spread to both subtropical and temperate areas throughout the world. Illinois appears to lie along the northern range-limit of this species; it is more common in southeastern and southwestern United States. In Illinois, Fir-leaved Celery was growing in low shrubbery near a parking lot in downtown Champaign, Illinois. It also occurred nearby in weedy turf grass along a roadside. In general, habitats of this plant include cropland, abandoned fields, roadside ditches, areas along railroads, gardens, neglected lawns, and areas around landscape shrubs. Fire and regular mowing are not tolerated. Nonetheless, this plant prefers habitats with a history of disturbance.
Faunal Associations: Floral-faunal relationships for Fir-leaved Celery are not well-understood for North America. Occasionally, White-tailed Deer browse on the foliage (Everitt et al., 1999). Livestock, including dairy cattle, sometimes browse on the foliage of this plant, as there have been some concerns about whether or not it can taint the flavor of milk.
Photographic Location: Low shrubbery and weedy turfgrass in downtown Champaign, Illinois, where this plant has persisted for several years. One of the photographs was taken indoors.
Comments: Sometimes the scientific name of Fir-leaved Celery is spelled Ciclospermum leptophyllum, and another scientific name of this plant is Apium leptophyllum. It also has other common names, including Marsh Parsley and Slender Celery. Fir-leaved Celery is remarkable for its narrowly lobed leaves and abundant umbels of tiny flowers. It is possible to confuse this plant with two other groups of annual plants in the Carrot family, viz. species of Mock Bishop-weed (Ptilimnium spp.) and Scaleseed (Spermolepis spp.), as they also have leaves with very narrow lobes and small white flowers. Species of Mock Bishop-weed differ by having larger compound umbels of flowers with more umbellets and the presence of floral bracts at the bases of their compound umbels. Species of Scaleseed can be distinguished by the bractlets at the bases of their umbellets and the presence of tubercles or bristles on their seeds. In contrast, Fir-leaved Celery lacks both floral bracts and bractlets and its seeds lack tubercles or bristles.
Both axillary and terminal umbels of flowers are produced in abundance. These umbels are usually compound, consisting of 2-3 umbellets (rarely with 4 umbellets), although sometimes they are simple. The compound umbels span about ¾–1¼" (20-32 mm.) across; their peduncles (basal stalks) are ¼–1" (6-24 mm.) long. The rays (basal stalklets) of the umbellets are ascending and divergent; they are ¼–¾" (6-20 mm.) in length. Individual umbellets span ¼–½" (6-12 mm.) across, consisting of 5-15 flowers; their pedicels are nearly zero to ¼" long. The peduncles, rays, and pedicels of each compound umbel are medium green, glabrous, and straight. Both the umbels and umbellets lack floral bracts. Individual flowers are only 1-2 mm. across when they are fully open. Each flower consists of 5 white petals, a toothless green calyx, 5 stamens, and a 2-celled ovary with a pair of short styles. The blooming period occurs during the summer and autumn, lasting about 2-3 months. Only a few flowers are in bloom at the same time.
Afterwards, the flowers are replaced by dry fruits (schizocarps); immature fruits are light green, while mature fruits turn brown; the latter soon fall to the ground. Each schizocarp consists of 2 hairless seeds. Individual seeds are 1.0–1.5 mm. long and asymmetrically ellipsoid in shape; one side of each seed is flat to slightly concave, while the other side is convex and conspicuously ribbed (3 ribs that are separated by 2 furrows). The root system consists of a slender taproot. This plant reproduces by reseeding itself.
Cultivation: The preference is full sun and moist conditions; a variety of soil types are tolerated. This plant will colonize drier ground, but it is vulnerable to hot dry weather. In some situations, this plant can spread aggressively, although this has not been a problem (thus far) in Illinois.
Range & Habitat: The non-native Fir-leaved Celery is a rare weed in Illinois. So far, it has occurred only in Champaign County (see Distribution Map). It is probably native to subtropical areas of Central and South America. However, it has spread to both subtropical and temperate areas throughout the world. Illinois appears to lie along the northern range-limit of this species; it is more common in southeastern and southwestern United States. In Illinois, Fir-leaved Celery was growing in low shrubbery near a parking lot in downtown Champaign, Illinois. It also occurred nearby in weedy turf grass along a roadside. In general, habitats of this plant include cropland, abandoned fields, roadside ditches, areas along railroads, gardens, neglected lawns, and areas around landscape shrubs. Fire and regular mowing are not tolerated. Nonetheless, this plant prefers habitats with a history of disturbance.
Faunal Associations: Floral-faunal relationships for Fir-leaved Celery are not well-understood for North America. Occasionally, White-tailed Deer browse on the foliage (Everitt et al., 1999). Livestock, including dairy cattle, sometimes browse on the foliage of this plant, as there have been some concerns about whether or not it can taint the flavor of milk.
Photographic Location: Low shrubbery and weedy turfgrass in downtown Champaign, Illinois, where this plant has persisted for several years. One of the photographs was taken indoors.
Comments: Sometimes the scientific name of Fir-leaved Celery is spelled Ciclospermum leptophyllum, and another scientific name of this plant is Apium leptophyllum. It also has other common names, including Marsh Parsley and Slender Celery. Fir-leaved Celery is remarkable for its narrowly lobed leaves and abundant umbels of tiny flowers. It is possible to confuse this plant with two other groups of annual plants in the Carrot family, viz. species of Mock Bishop-weed (Ptilimnium spp.) and Scaleseed (Spermolepis spp.), as they also have leaves with very narrow lobes and small white flowers. Species of Mock Bishop-weed differ by having larger compound umbels of flowers with more umbellets and the presence of floral bracts at the bases of their compound umbels. Species of Scaleseed can be distinguished by the bractlets at the bases of their umbellets and the presence of tubercles or bristles on their seeds. In contrast, Fir-leaved Celery lacks both floral bracts and bractlets and its seeds lack tubercles or bristles.
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文章
Miss Chen
2018年08月09日
Description: This plant is a summer annual about 2-6' tall that is unbranched below, but branched above, with erect to ascending stems. The stems are light green to dark red, terete, and either glabrous or sparsely short-pubescent. Pairs of opposite compound leaves are widely spaced along the stems. Individual compound leaves are up to 5" long and 3½" across; they are usually bipinnate with narrowly linear lobes (about 1 mm. across) that are light to medium green and glabrous. The compound leaves are either sessile or they have short petioles up to ¼" long.
The upper stems terminate in individual flowerheads about 2-3" across that are on long naked peduncles (4-8" long). The peduncles have characteristics that are similar to the stems. Each flowerhead consists of about 8 ray florets that surround numerous tiny disk florets. The ray florets are sterile, while the disk florets are perfect and fertile. The petaloid extensions of the ray florets are white, pink, or magenta; sometimes they are bicolored. In addition, these petaloid extensions are obovate in shape and their outer edges are shallowly cleft. The circular perimeter of the disk florets spans about ½" across; it is relatively small in relation to the diameter of the flowerhead. Individual disk florets are about ¼" long, bright yellow, and narrowly cylindrical. At the base of the flowerhead, there are floral bracts (phyllaries) in 2 series; there are about 8 floral bractsDistribution Map in each series. The outer floral bracts are green and lanceolate, while the inner floral bracts are purple and ovate. Both types of bracts are about ½" in length. Together, the floral bracts form a shallow cup at the base of the flowerhead. The blooming period occurs from mid-summer into the fall, lasting 2-3 months. Afterwards, the disk florets of each flowerhead are replaced by narrowly cylindrical-angular achenes about ½" long. Each slightly curved achene is slightly swollen toward its outer tip, where there is a minute beak. A pair of awns about 1 mm. in length is sometimes present at this beak. The outer surface of each mature achene is dark-colored. The root system consists of a taproot. This plants reproduces by reseeding itself.
Cultivation: The preference is full sun, mesic or dry-mesic conditions, and a mildly acidic to alkaline soil containing loam, clay loam, gravel, or sand. Once the seeds germinate, growth and development is rapid. Wild plants tend to be shorter and bloom less abundantly than garden plants in fertile soil, otherwise they appear much the same.
Range & Habitat: The introduced Common Cosmos rarely naturalizes in Illinois, where it has been reported in only a few counties. Wild populations of this plant rarely persist. Common Cosmos was introduced into the United States as an ornamental flowering plant from Mexico or tropical America, and it is still commonly cultivated. Habitats include fallow or abandoned fields, roadsides, areas along railroads, and waste areas. Habitats with a history of disturbance and relatively open ground are preferred.
Faunal Associations: Very little is known about the floral-faunal relationships for this introduced plant in North America. Butterflies and possibly other insects visit the flowers for nectar and/or pollen. Insects that feed destructively on Cosmos spp. include Macrosteles fascifrons (Aster Leafhopper) and the polyphagous caterpillars of Rachiplusia ou (Gray Looper Moth).
Photographic Location: A fallow field near Champaign, Illinois.
Comments: Because of its attractive flowers, fine fern-like foliage, and ease of cultivation, it is easy to understand why Common Cosmos remains a popular garden plant. There are many cultivars to choose from. While Common Cosmos occasionally reseeds itself, it has not been invasive in Illinois. It is easy to identify in the wild because nothing else closely resembles it, except other non-native Cosmos spp., that so far have not escaped from cultivation within the state. Some Coreopsis spp. have finely divided foliage and similar flowerheads, but they tend to be shorter plants and their flowerheads are usually yellow.
The upper stems terminate in individual flowerheads about 2-3" across that are on long naked peduncles (4-8" long). The peduncles have characteristics that are similar to the stems. Each flowerhead consists of about 8 ray florets that surround numerous tiny disk florets. The ray florets are sterile, while the disk florets are perfect and fertile. The petaloid extensions of the ray florets are white, pink, or magenta; sometimes they are bicolored. In addition, these petaloid extensions are obovate in shape and their outer edges are shallowly cleft. The circular perimeter of the disk florets spans about ½" across; it is relatively small in relation to the diameter of the flowerhead. Individual disk florets are about ¼" long, bright yellow, and narrowly cylindrical. At the base of the flowerhead, there are floral bracts (phyllaries) in 2 series; there are about 8 floral bractsDistribution Map in each series. The outer floral bracts are green and lanceolate, while the inner floral bracts are purple and ovate. Both types of bracts are about ½" in length. Together, the floral bracts form a shallow cup at the base of the flowerhead. The blooming period occurs from mid-summer into the fall, lasting 2-3 months. Afterwards, the disk florets of each flowerhead are replaced by narrowly cylindrical-angular achenes about ½" long. Each slightly curved achene is slightly swollen toward its outer tip, where there is a minute beak. A pair of awns about 1 mm. in length is sometimes present at this beak. The outer surface of each mature achene is dark-colored. The root system consists of a taproot. This plants reproduces by reseeding itself.
Cultivation: The preference is full sun, mesic or dry-mesic conditions, and a mildly acidic to alkaline soil containing loam, clay loam, gravel, or sand. Once the seeds germinate, growth and development is rapid. Wild plants tend to be shorter and bloom less abundantly than garden plants in fertile soil, otherwise they appear much the same.
Range & Habitat: The introduced Common Cosmos rarely naturalizes in Illinois, where it has been reported in only a few counties. Wild populations of this plant rarely persist. Common Cosmos was introduced into the United States as an ornamental flowering plant from Mexico or tropical America, and it is still commonly cultivated. Habitats include fallow or abandoned fields, roadsides, areas along railroads, and waste areas. Habitats with a history of disturbance and relatively open ground are preferred.
Faunal Associations: Very little is known about the floral-faunal relationships for this introduced plant in North America. Butterflies and possibly other insects visit the flowers for nectar and/or pollen. Insects that feed destructively on Cosmos spp. include Macrosteles fascifrons (Aster Leafhopper) and the polyphagous caterpillars of Rachiplusia ou (Gray Looper Moth).
Photographic Location: A fallow field near Champaign, Illinois.
Comments: Because of its attractive flowers, fine fern-like foliage, and ease of cultivation, it is easy to understand why Common Cosmos remains a popular garden plant. There are many cultivars to choose from. While Common Cosmos occasionally reseeds itself, it has not been invasive in Illinois. It is easy to identify in the wild because nothing else closely resembles it, except other non-native Cosmos spp., that so far have not escaped from cultivation within the state. Some Coreopsis spp. have finely divided foliage and similar flowerheads, but they tend to be shorter plants and their flowerheads are usually yellow.
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Miss Chen
2018年08月07日
Asparagus fern (Protasparagus densiflorus) is not a real fern, but an evergreen, perennial member of the lily family. Also referred to as emerald fern and foxtail fern, the plant is a native of South Africa. Asparagus fern is widely used as an ornamental plant for containers and as a groundcover. The plant has however escaped cultivation in many regions and is classified as an invasive weed. Asparagus ferns cannot be propagated with cuttings.
Propagation Method
The recommended way to propagate new asparagus plants is with the use of seeds or by dividing the plants, as suggested by online plant resource Floridata. Though cuttings are a very commonly used method of plant propagation, it cannot be applied to the asparagus fern. The University of Missouri Extension also recommends propagating asparagus fern by division.
Propagating by Division
The best time to divide asparagus fern is during spring when the plant is growing actively. Prepare new pots for the new plants. Carefully slide out the plant from the containers. Using a sharp scissors, cut the root ball into multiple sections depending on the size of the plant. Each section should have a good number of roots, leaves and stems. Plant each section in individual pots and water well. Keep plants out of direct sunlight until the plants are established and growing well.
Propagating with Seed
Buy fresh seed from a reliable source and soak overnight in slightly warm water. Sow in a medium sized pot filled with a good potting soil. Do not sow very deep but just below the soil surface. Keep pot at room temperature. Asparagus fern seeds germinate very slowly with a germination time of a month or longer. For planting outdoors, start seeds 14 to 18 months prior to last frost date in the area. (Reference 5)
Growth Requirements
Asparagus fern grows best in fertile, well-drained soil amended with humus. Plant in areas of full sun to deep shade. Plants tend to start yellowing if exposed to very hot sun. Water enough to keep soil consistently moist. Divide the plants every one to two years to maintain healthy growth. Prior to dividing, cut the stems to a length of about 6 inches to minimize long mingling stems.
Propagation Method
The recommended way to propagate new asparagus plants is with the use of seeds or by dividing the plants, as suggested by online plant resource Floridata. Though cuttings are a very commonly used method of plant propagation, it cannot be applied to the asparagus fern. The University of Missouri Extension also recommends propagating asparagus fern by division.
Propagating by Division
The best time to divide asparagus fern is during spring when the plant is growing actively. Prepare new pots for the new plants. Carefully slide out the plant from the containers. Using a sharp scissors, cut the root ball into multiple sections depending on the size of the plant. Each section should have a good number of roots, leaves and stems. Plant each section in individual pots and water well. Keep plants out of direct sunlight until the plants are established and growing well.
Propagating with Seed
Buy fresh seed from a reliable source and soak overnight in slightly warm water. Sow in a medium sized pot filled with a good potting soil. Do not sow very deep but just below the soil surface. Keep pot at room temperature. Asparagus fern seeds germinate very slowly with a germination time of a month or longer. For planting outdoors, start seeds 14 to 18 months prior to last frost date in the area. (Reference 5)
Growth Requirements
Asparagus fern grows best in fertile, well-drained soil amended with humus. Plant in areas of full sun to deep shade. Plants tend to start yellowing if exposed to very hot sun. Water enough to keep soil consistently moist. Divide the plants every one to two years to maintain healthy growth. Prior to dividing, cut the stems to a length of about 6 inches to minimize long mingling stems.
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Miss Chen
2018年08月06日
Description: This perennial plant is a herbaceous vine that produces stems 2-4' long. The stems are usually glabrous, but are sometimes hairy where new growth occurs. The alternate leaves are 1-2' long and half as much across. They are often sagittate (arrowhead-shaped), but are variable and can assume other forms as well. Their margins are smooth and occasionally slightly ciliate. Long slender petioles connect the leaves with the stems. A slender flowering stalk may develop from the base of a petiole. This stalk occasionally branches and can produce 1-3 flowers. The corolla of a flower is funnelform in shape and up to 1" across; it is usually white, sometimes with light pink patterns. The 5 lobes of the corolla are very shallow and barely perceptible. Toward the throat of the corolla is a patch of yellow and the reproductive parts, consisting of 5 stamens and a pistil with a divided style. These reproductive parts are usually white, although the anthers may be pink or light purple in flowers with pink corollas. At the base of the flower, there are 5 green sepals that are much smaller than the corolla. Up to 1" below the base of a flower, there are a pair of small green bracts on the flowering stalk.
The blooming period can occur from late spring to early fall, and can span several months, even though individual flowers persist for only a single day, usually opening during the morning and closing by late afternoon. A hairless and well-rounded seed capsule about ¼" long replaces each flower; each 2-celled capsule contains 4 seeds. These dark seeds are 3-angled and oblong, but tapering somewhat at the ends. Each seed usually has 2 flat sides and 1 convex side; it is about 1/8" long. The root system consists of a slender taproot that branches frequently; it can extend 20' into the ground. Rhizomes are also produced in abundance, so that this plant often forms vegetative colonies.
Cultivation: Field Bindweed prefers full sunlight and mesic to dry conditions. It has considerable drought tolerance, and flourishes in poor soil that contains sand, gravel, or hardpan clay. It will also grow in moist fertile soil, but dislikes competition from taller plants. Eradication of this plant is difficult, as mechanical cultivation often spreads the rhizomes around, producing new plants. Because of the deep root system, it has been known to survive bulldozer operations. It can also persist in lawns, notwithstanding regular lawn-mowing. The application of broadleaf herbicides can be an effective control measure, if it is repeated as needed.
Range & Habitat: Field Bindweed is a common plant that has been reported from most counties in Illinois (see Distribution Map); it is native to Eurasia. This plant continues to spread and probably occurs in every county of the state. Habitats include lawns, gardens, fields, clay banks, areas along roadsides and railroads (including ballast), vacant lots, and miscellaneous waste areas. This plant occurs primarily in disturbed areas.
Faunal Associations: Mostly long-tongued bees visit the flowers for nectar, including bumblebees and little carpenter bees (Ceratina spp.). In addition, specialist bees that are attracted to funnelform flowers also visit the flowers for nectar, including Melitoma taurea (Mallow Bee) and Cemolobus ipomoeae (Morning Glory Bee). The adults and larvae of several tortoise beetles are known to feed destructively on the foliage of Field Bindweed, including Charidotella sexpunctata (Golden Tortoise Beetle), Chelymorpha cassidea (Argus Tortoise Beetle), Deloyala guttata (Mottled Tortoise Beetle), and Jonthonota nigripes (Black-legged Tortoise Beetle). Other beetles that feed on this plant include Chaetocnema confinis (Sweet Potato Flea Beetle) and Typophorus nigritus (Sweet Potato Leaf Beetle); see Clark et al. (2004). The larvae of a sawfly, Sphacophilus cellularis, feed on the leaves of bindweeds (Convolvulus spp.), as do the larvae of several moths, including Bedellia somnulentella (Morning Glory Leafminer), Spragueia leo (Common Spragueia), Emmelina monodactyla (Morning Glory Plume Moth), and Agrius cingulatus (Pink-spotted Hawk Moth); see Smith (2006), Cranshaw (2004), Covell (1984/2005), and Wagner (2005). Field Bindweed is not a preferred food source for mammalian herbivores because the foliage is mildly toxic. Furthermore, there have been reports of the rootstocks poisoning swine.
Photographic Location: Along a railroad in Urbana, Illinois. This plant is very common in the area.
Comments: Field Bindweed is an attractive plant while it is in flower, but it can be very aggressive and persistent. The flowers are smaller in size than Calystegia sepium (Hedge Bindweed) and Ipomoea pandurata (Wild Sweet Potato). Its leaves are sagittate, while the leaves of Ipomoea pandurata (Wild Sweet Potato) and Ipomoea lacunosa (Small White Morning Glory) are cordate.
The blooming period can occur from late spring to early fall, and can span several months, even though individual flowers persist for only a single day, usually opening during the morning and closing by late afternoon. A hairless and well-rounded seed capsule about ¼" long replaces each flower; each 2-celled capsule contains 4 seeds. These dark seeds are 3-angled and oblong, but tapering somewhat at the ends. Each seed usually has 2 flat sides and 1 convex side; it is about 1/8" long. The root system consists of a slender taproot that branches frequently; it can extend 20' into the ground. Rhizomes are also produced in abundance, so that this plant often forms vegetative colonies.
Cultivation: Field Bindweed prefers full sunlight and mesic to dry conditions. It has considerable drought tolerance, and flourishes in poor soil that contains sand, gravel, or hardpan clay. It will also grow in moist fertile soil, but dislikes competition from taller plants. Eradication of this plant is difficult, as mechanical cultivation often spreads the rhizomes around, producing new plants. Because of the deep root system, it has been known to survive bulldozer operations. It can also persist in lawns, notwithstanding regular lawn-mowing. The application of broadleaf herbicides can be an effective control measure, if it is repeated as needed.
Range & Habitat: Field Bindweed is a common plant that has been reported from most counties in Illinois (see Distribution Map); it is native to Eurasia. This plant continues to spread and probably occurs in every county of the state. Habitats include lawns, gardens, fields, clay banks, areas along roadsides and railroads (including ballast), vacant lots, and miscellaneous waste areas. This plant occurs primarily in disturbed areas.
Faunal Associations: Mostly long-tongued bees visit the flowers for nectar, including bumblebees and little carpenter bees (Ceratina spp.). In addition, specialist bees that are attracted to funnelform flowers also visit the flowers for nectar, including Melitoma taurea (Mallow Bee) and Cemolobus ipomoeae (Morning Glory Bee). The adults and larvae of several tortoise beetles are known to feed destructively on the foliage of Field Bindweed, including Charidotella sexpunctata (Golden Tortoise Beetle), Chelymorpha cassidea (Argus Tortoise Beetle), Deloyala guttata (Mottled Tortoise Beetle), and Jonthonota nigripes (Black-legged Tortoise Beetle). Other beetles that feed on this plant include Chaetocnema confinis (Sweet Potato Flea Beetle) and Typophorus nigritus (Sweet Potato Leaf Beetle); see Clark et al. (2004). The larvae of a sawfly, Sphacophilus cellularis, feed on the leaves of bindweeds (Convolvulus spp.), as do the larvae of several moths, including Bedellia somnulentella (Morning Glory Leafminer), Spragueia leo (Common Spragueia), Emmelina monodactyla (Morning Glory Plume Moth), and Agrius cingulatus (Pink-spotted Hawk Moth); see Smith (2006), Cranshaw (2004), Covell (1984/2005), and Wagner (2005). Field Bindweed is not a preferred food source for mammalian herbivores because the foliage is mildly toxic. Furthermore, there have been reports of the rootstocks poisoning swine.
Photographic Location: Along a railroad in Urbana, Illinois. This plant is very common in the area.
Comments: Field Bindweed is an attractive plant while it is in flower, but it can be very aggressive and persistent. The flowers are smaller in size than Calystegia sepium (Hedge Bindweed) and Ipomoea pandurata (Wild Sweet Potato). Its leaves are sagittate, while the leaves of Ipomoea pandurata (Wild Sweet Potato) and Ipomoea lacunosa (Small White Morning Glory) are cordate.
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Miss Chen
2018年08月06日
Description: This perennial herbaceous plant consists of a pair of leaves that are nearly basal and a single raceme of flowers. The leaf blades are 5-10" long, 3-5" across, and more or less erect; they are oval-ovate in shape and smooth (entire) along their margins. Both the lower and upper leaf surfaces are medium to dark green, glabrous, and sometimes slightly glaucous. Leaf venation is parallel. The leaves taper into petioles about 1½–3" long that wrap around a short basal stalk that is partially underground. Between the leaves, there develops a raceme of flowers about 4-9" long. This raceme is shorter than the leaves and it tends to nod toward its apex; there are 6-16 flowers per raceme. The central stalk of the raceme is medium green, terete, somewhat slender, and glabrous. The nodding flowers usually occur along one side of the raceme from pedicels that are up to ½" long; these pedicels are light green, terete, and glabrous. At the bases of these pedicels, there are solitary floral bracts. These floral bracts are up to 8 mm. (1/3") long, light green to nearly white, and narrowly lanceolate to ovate in shape; they are shorter than the corresponding pedicels.
The white corollas of these flowers are about 8 mm. (1/3") long and similarly across; they are campanulate (bell-shaped) with 6 short lobes that curve outward. Within the corolla of each flower, there are 6 stamens with short filaments and a single style with a tripartite stigma. The ovary of each flower has 3 cells. The blooming period occurs from late spring to early summer, lasting about 3 weeks. The flowers are quite fragrant. When the flowers are successfully cross-pollinated from the pollen of genetically distinct plants, they develop red berries that are 6-8 mm. across and globoid in shape (one berry per fertile flower). The interior of each berry is juicy, containing 1-6 seeds. These seeds are 3-4 mm. long and light brown with darker scar tissue at their bases; they are more or less ovoid in shape, but also rather irregular and chunky. In North America, most flowering plants fail to produce berries. The root system is fibrous and rhizomatous. Dense colonies of clonal plants are produced from the dense network of rhizomes; these colonies tend to exclude other species of plants.
Cultivation: The preference is dappled sunlight to medium shade, moist to mesic conditions, and a rich loamy soil with abundant organic material. Once it becomes established, this plant is long-lived, and it will spread slowly via its rhizomes. The leaves remain green throughout the summer until frost occurs during the autumn. Propagation of new plants is easiest by division of the rhizomes. If you want Lily-of-the-Valley to produce the attractive red berries, then you will need to plant genetically distinct plants in proximity to each other from two or more sources.
Range & Habitat: Lily-of-the-Valley has escaped from cultivation primarily in NE Illinois (see Distribution Map), where it is uncommon in natural areas. This species was introduced into the United States from Europe as an ornamental plant; it is often grown in gardens because of the attractive foliage and flowers. In addition to the typical European variety that is described here (Convallaria majalis majalis), there is also a North American variety of Lily-of-the-Valley (Convallaria majalis montana) that is native to the region of the Appalachian mountains. However, this North American variety is cultivated much less often than the European variety of Lily-of-the-Valley, and it has not naturalized in Illinois to anyone's knowledge. In Illinois, the European variety of Lily-of-the-Valley has naturalized in such habitats as tamarack bogs, rich deciduous woodlands, pioneer cemetery prairies, oak savannas near pioneer cemetery prairies, and abandoned homestead sites. At some of these habitats, Lily-of-the-Valley was deliberately introduced, where it has persisted for several decades, notwithstanding long neglect.
Faunal Associations: Bumblebees and honeybees collect pollen from the flowers of Lily-of-the-Valley; nectar may not be produced (Vandepitte, 2010; Müller 1873/1883). Among bumblebee species, Bombus vagans and Bombus pensylvanicus have been observed to visit the flowers (Mathews, 1912). Insects that feed on the foliage and other parts of this plant are limited in number. An insect that was accidentally introduced into North America from Europe, Lilioceris lilii (Lily Leaf Beetle), feeds on the leaves, while an aphid, Macrosiphum pechumani, sucks sap from this plant (Clark et al., 2004; Blackman & Eastop, 2013). The red berries probably attract birds and possibly some rodents, although because these berries are rarely produced in North America, it is unknown which species would consume them. According to Eriksson (1999), the seeds of these berries are eaten by voles and wood rats in Europe. Because all parts of Lily-of-the-Valley contain cardiac glycosides that are toxic, it is largely ignored by mammalian herbivores. Overall, the ecological value of this plant appears to be low.
Photographic Location: A wooded area at Meadowbrook Park in Urbana, Illinois, and a flower garden in the same city.
Comments: In addition to its cultivation in gardens, Lily-of-the-Valley has economic significance in the perfume and pharmaceutical industries. For the latter, it has been used as a source of heart medication. There are two varieties of Lily-of-the-Valley: the typical European variety (Convallaria majalis majalis) and the North American variety (Convallaria majalis montana). This latter variety can be distinguished by its larger floral bracts (at least 10 mm. in length) and the fine green lines along the midribs of its tepals (the tepals have been joined together to form a bell-shaped corolla for each flower). As compared to the European variety, the North American variety also appears to be less aggressive in forming large dense colonies of clonal plants.
The white corollas of these flowers are about 8 mm. (1/3") long and similarly across; they are campanulate (bell-shaped) with 6 short lobes that curve outward. Within the corolla of each flower, there are 6 stamens with short filaments and a single style with a tripartite stigma. The ovary of each flower has 3 cells. The blooming period occurs from late spring to early summer, lasting about 3 weeks. The flowers are quite fragrant. When the flowers are successfully cross-pollinated from the pollen of genetically distinct plants, they develop red berries that are 6-8 mm. across and globoid in shape (one berry per fertile flower). The interior of each berry is juicy, containing 1-6 seeds. These seeds are 3-4 mm. long and light brown with darker scar tissue at their bases; they are more or less ovoid in shape, but also rather irregular and chunky. In North America, most flowering plants fail to produce berries. The root system is fibrous and rhizomatous. Dense colonies of clonal plants are produced from the dense network of rhizomes; these colonies tend to exclude other species of plants.
Cultivation: The preference is dappled sunlight to medium shade, moist to mesic conditions, and a rich loamy soil with abundant organic material. Once it becomes established, this plant is long-lived, and it will spread slowly via its rhizomes. The leaves remain green throughout the summer until frost occurs during the autumn. Propagation of new plants is easiest by division of the rhizomes. If you want Lily-of-the-Valley to produce the attractive red berries, then you will need to plant genetically distinct plants in proximity to each other from two or more sources.
Range & Habitat: Lily-of-the-Valley has escaped from cultivation primarily in NE Illinois (see Distribution Map), where it is uncommon in natural areas. This species was introduced into the United States from Europe as an ornamental plant; it is often grown in gardens because of the attractive foliage and flowers. In addition to the typical European variety that is described here (Convallaria majalis majalis), there is also a North American variety of Lily-of-the-Valley (Convallaria majalis montana) that is native to the region of the Appalachian mountains. However, this North American variety is cultivated much less often than the European variety of Lily-of-the-Valley, and it has not naturalized in Illinois to anyone's knowledge. In Illinois, the European variety of Lily-of-the-Valley has naturalized in such habitats as tamarack bogs, rich deciduous woodlands, pioneer cemetery prairies, oak savannas near pioneer cemetery prairies, and abandoned homestead sites. At some of these habitats, Lily-of-the-Valley was deliberately introduced, where it has persisted for several decades, notwithstanding long neglect.
Faunal Associations: Bumblebees and honeybees collect pollen from the flowers of Lily-of-the-Valley; nectar may not be produced (Vandepitte, 2010; Müller 1873/1883). Among bumblebee species, Bombus vagans and Bombus pensylvanicus have been observed to visit the flowers (Mathews, 1912). Insects that feed on the foliage and other parts of this plant are limited in number. An insect that was accidentally introduced into North America from Europe, Lilioceris lilii (Lily Leaf Beetle), feeds on the leaves, while an aphid, Macrosiphum pechumani, sucks sap from this plant (Clark et al., 2004; Blackman & Eastop, 2013). The red berries probably attract birds and possibly some rodents, although because these berries are rarely produced in North America, it is unknown which species would consume them. According to Eriksson (1999), the seeds of these berries are eaten by voles and wood rats in Europe. Because all parts of Lily-of-the-Valley contain cardiac glycosides that are toxic, it is largely ignored by mammalian herbivores. Overall, the ecological value of this plant appears to be low.
Photographic Location: A wooded area at Meadowbrook Park in Urbana, Illinois, and a flower garden in the same city.
Comments: In addition to its cultivation in gardens, Lily-of-the-Valley has economic significance in the perfume and pharmaceutical industries. For the latter, it has been used as a source of heart medication. There are two varieties of Lily-of-the-Valley: the typical European variety (Convallaria majalis majalis) and the North American variety (Convallaria majalis montana). This latter variety can be distinguished by its larger floral bracts (at least 10 mm. in length) and the fine green lines along the midribs of its tepals (the tepals have been joined together to form a bell-shaped corolla for each flower). As compared to the European variety, the North American variety also appears to be less aggressive in forming large dense colonies of clonal plants.
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Miss Chen
2018年08月06日
Raceme of FlowersDescription: This annual plant is about 2-3' tall. It often produces 2 or 3 forking stems that are themselves little branched. These stems are round and pubescent, although with age they often become glabrous. The alternate leaves are sessile, palmately divided, and up to 3" long and across. Their lobes repeatedly subdivide into smaller lobes that are narrowly linear, providing the leaves with a lacy appearance. They are slightly pubescent and often have a silky appearance. The stems terminate into spike-like racemes of blue-violet flowers. These racemes can be up to 1' in length. Each flower is about 2" across, consisting of 5 petal-like sepals, 4 petals, a single pistil, and some stamens with light blue anthers. The upper sepal forms a hood in front and an upward-curving spur in back about 1" long. The middle and lower sepals are well-rounded and spreading. The 2 upper petals form a protective inner hood of the reproductive organs; they are not fused together. The 2 lower petals form a V-shaped landing pad for visiting insects. The outer sepals are larger in size than the inner petals. At the base of each flower is a slender pedicel about 1" long. The blooming period occurs during the summer and lasts about 1-2 months. Each flower is replaced by a pubescent follicle containing numerous small black seeds. These seeds are small enough to be dispersed by gusts of wind. The root system is a slender branching taproot. This plant spreads by reseeding itself, and may form colonies at favorable sites, although it usually doesn't persist.
Cultivation: The preference is full sunlight, moist to mesic conditions, and a loamy fertile soil. This plant develops quickly, shooting up like a rocket, hence the common name. However, in poor soil and droughty conditions, growth will be stunted.
Range & Habitat: Rocket Larkspur is an occasional plant that has been reported from scattered counties in Illinois, except in the NW area of the state (see Distribution Map). Habitats consist of areas along railroads and roadsides, banks of drainage ditches, abandoned fields, vacant lots, and flower gardens. There is a strong preference for disturbed areas; it does not appear to invade higher quality natural habitats to any significant extent, at least in Illinois. Rocket Larkspur originated from the Mediterranean area of Europe; it was introduced into the United States as an ornamental plant.
Faunal Associations: Long-tongued bees pollinate the flowers, especially bumblebees. Butterflies may visit the flowers occasionally, but they are unlikely to be effective at pollination. The larvae of a fly, Phytomyza delphinivora, mine the leaves of Consolida spp. (larkspurs), and the caterpillars of a polyphagous moth, Megalographa biloba (Bilobed Looper Moth), also feed on the foliage (Cranshaw, 2004; Wagner, 2005). Because of the presence of an alkaloid, delphinine, both the foliage and small seeds are quite toxic. Therefore, they are of little value as a food source to birds and mammals. Like the closely related Delphinium spp. (delphiniums), the larkspurs occasionally poison livestock.
Photographic Location: The lower bank of a large drainage ditch in Urbana, Illinois.
Comments: Rocket Larkspur produces attractive flowers on long spike-like racemes, therefore it is not surprising that this species is grown in flower gardens, from which it occasionally escapes. Unlike the Delphiniums, which are perennial plants, the Consolida spp. (Larkspurs) are annual plants. While the flower of a Delphinium has 3 pistils, the flower of a Larkspur has only a single pistil. The only other Larkspur that escapes into the wild in Illinois is Consolida regalis (Forking Larkspur). This is another introduced plant from the Mediterranean area of Europe that is less commonly encountered than Rocket Larkspur. Its flowers are often a lighter shade of blue-violet than Rocket Larkspur, and the upper petals of its flowers are fused together. The follicles (seed capsules) of Forking Larkspur are glabrous, while the follicles of Rocket Larkspur are pubescent.
Cultivation: The preference is full sunlight, moist to mesic conditions, and a loamy fertile soil. This plant develops quickly, shooting up like a rocket, hence the common name. However, in poor soil and droughty conditions, growth will be stunted.
Range & Habitat: Rocket Larkspur is an occasional plant that has been reported from scattered counties in Illinois, except in the NW area of the state (see Distribution Map). Habitats consist of areas along railroads and roadsides, banks of drainage ditches, abandoned fields, vacant lots, and flower gardens. There is a strong preference for disturbed areas; it does not appear to invade higher quality natural habitats to any significant extent, at least in Illinois. Rocket Larkspur originated from the Mediterranean area of Europe; it was introduced into the United States as an ornamental plant.
Faunal Associations: Long-tongued bees pollinate the flowers, especially bumblebees. Butterflies may visit the flowers occasionally, but they are unlikely to be effective at pollination. The larvae of a fly, Phytomyza delphinivora, mine the leaves of Consolida spp. (larkspurs), and the caterpillars of a polyphagous moth, Megalographa biloba (Bilobed Looper Moth), also feed on the foliage (Cranshaw, 2004; Wagner, 2005). Because of the presence of an alkaloid, delphinine, both the foliage and small seeds are quite toxic. Therefore, they are of little value as a food source to birds and mammals. Like the closely related Delphinium spp. (delphiniums), the larkspurs occasionally poison livestock.
Photographic Location: The lower bank of a large drainage ditch in Urbana, Illinois.
Comments: Rocket Larkspur produces attractive flowers on long spike-like racemes, therefore it is not surprising that this species is grown in flower gardens, from which it occasionally escapes. Unlike the Delphiniums, which are perennial plants, the Consolida spp. (Larkspurs) are annual plants. While the flower of a Delphinium has 3 pistils, the flower of a Larkspur has only a single pistil. The only other Larkspur that escapes into the wild in Illinois is Consolida regalis (Forking Larkspur). This is another introduced plant from the Mediterranean area of Europe that is less commonly encountered than Rocket Larkspur. Its flowers are often a lighter shade of blue-violet than Rocket Larkspur, and the upper petals of its flowers are fused together. The follicles (seed capsules) of Forking Larkspur are glabrous, while the follicles of Rocket Larkspur are pubescent.
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Miss Chen
2018年08月06日
Description: This is a biennial plant. During the 1st year, it consists of a rosette of basal leaves spanning about ¾–1½' across. During the 2nd year, it produces a flowering stalk that becomes 3-7' tall, branching occasionally above. The stems are round, glabrous, light green, and purple-spotted; they often appear to be ribbed because of longitudinal veins. The alternate leaves are up to 18" long and 12" across, becoming smaller as they ascend the stems. They are double or triple pinnately compound, triangular-ovate in outline, and hairless. These leaves have a fern-like appearance and a somewhat filmy upper surface. The basal and lower leaves have long petioles, while the upper leaves have shorter petioles. The base of each petiole is partially covered by a sheath. The ultimate leaflets of the compound leaves are about 1/3" (8 mm.) long, lanceolate to ovate in shape, pinnately cleft or dentate, and hairless.
The upper stems terminate in compound umbels of small white flowers. These compound umbels span about 2-5" across and consist of about 8-16 umbellets. Each umbellet consists of about 12-25 flowers. Individual flowers span only 1/8" (3 mm.) across when they are fully open. Each flower has 5 white obcordate petals, 5 spreading white stamens, and a white nectar pad in the center. At the base of the compound umbel are several floral bracts that are ovate-lanceolate with elongated tips; there are also several bractlets at the base of each umbel. These bractlets are ovate-lanceolate like the bracts, but smaller in size. The blooming period occurs from late spring to mid-summer and lasts about 1-2 months. Each flower is replaced by a schizocarp that is broadly ovate and somewhat flattened; it has several longitudinal ribs that are wavy. The root system consists of a white taproot. This plant spreads by reseeding itself; it often forms colonies at favorable sites.
Cultivation: The preference is full sun to light shade, moist conditions, and a fertile loamy soil. Most vegetative growth occurs during the spring. After blooming and developing seeds, the foliage turns yellow and withers away later in the summer. In removing this plant from a given area, don't pull it out using your bare hands. It is better to wear washable gloves while hand-pulling a limited number of plants. For large areas of infestation, it is best to apply broadleaf herbicides or mow down the plants during the spring shortly before they develop flowers.
Range & Habitat: Poison Hemlock is a common plant that occurs in many areas of Illinois, except for scattered counties in north and south (see Distribution Map). This plant is undoubtedly more common than official records indicate and it is still spreading to new areas of the state. Poison Hemlock is native to Europe and the Middle East, and it was introduced into North America either accidentally or deliberately.
Habitats include edges of degraded wetlands and prairies, low-lying areas along small rivers, banks of drainage ditches, thickets, woodland borders, fence rows, low-lying areas along railroads and roads, pastures, and abandoned fields. This plant is usually found in disturbed areas, but it occasionally invades native habitats.
Faunal Associations: The nectar of the flowers attracts a wide variety of flies, beetles, sawflies, and wasps, including Ichneumonid and other parasitoid wasps. Caterpillars of the butterfly, Papilio polyxenes asterius (Eastern Black Swallowtail), feed on the foliage, notwithstanding its extreme toxicity (personal observation). This toxicity is the result of the alkaloid coniine and other chemicals, which can be found in all parts of Poison Hemlock, including the seeds and roots. Another insect, Orthops scutellatus (Carrot Plant Bug), eats the seeds of this plant and other members of the Carrot family (Knight, 1941). Poison Hemlock is also a summer host plant of several aphids, including Dysaphis apiifolia (Hawthorn-Parsley Aphid), Hyadaphis foeniculi (Fennel Aphid), and Hyadaphis passerinii (Honeysuckle Aphid); see Blackman & Eastop (2013). Mammalian herbivores won't touch the foliage because of its bitter rank odor and extreme toxicity. Just a small portion of the ingested plant can be fatal to humans.
Comments: The ancient Athenians used the juices of this plant to execute their prisoners, including Socrates during 399 B.C. Death is caused by respiratory arrest and heart failure. Poison Hemlock is a tall and imposing plant that appears to be increasingly common. Many people walk past this species without even realizing what it is. Because there are many members of the Carrot family with small white flowers, it can be somewhat difficult to correctly identify this plant. Poison Hemlock has the following key features: 1) it is often tall-growing, 1) the foliage is at least double pinnate and fern-like in appearance, 2) the foliage has a bitter rank odor, especially when it is bruised, 3) the hairless stems have purple spots, 4) there are undivided bracts at the base of the compound umbel and undivided bractlets at the base of the umbellets, and 5) the small leaflets are pinnately cleft or dentate. Other members of the Carrot family lack one or more of these key features.
The upper stems terminate in compound umbels of small white flowers. These compound umbels span about 2-5" across and consist of about 8-16 umbellets. Each umbellet consists of about 12-25 flowers. Individual flowers span only 1/8" (3 mm.) across when they are fully open. Each flower has 5 white obcordate petals, 5 spreading white stamens, and a white nectar pad in the center. At the base of the compound umbel are several floral bracts that are ovate-lanceolate with elongated tips; there are also several bractlets at the base of each umbel. These bractlets are ovate-lanceolate like the bracts, but smaller in size. The blooming period occurs from late spring to mid-summer and lasts about 1-2 months. Each flower is replaced by a schizocarp that is broadly ovate and somewhat flattened; it has several longitudinal ribs that are wavy. The root system consists of a white taproot. This plant spreads by reseeding itself; it often forms colonies at favorable sites.
Cultivation: The preference is full sun to light shade, moist conditions, and a fertile loamy soil. Most vegetative growth occurs during the spring. After blooming and developing seeds, the foliage turns yellow and withers away later in the summer. In removing this plant from a given area, don't pull it out using your bare hands. It is better to wear washable gloves while hand-pulling a limited number of plants. For large areas of infestation, it is best to apply broadleaf herbicides or mow down the plants during the spring shortly before they develop flowers.
Range & Habitat: Poison Hemlock is a common plant that occurs in many areas of Illinois, except for scattered counties in north and south (see Distribution Map). This plant is undoubtedly more common than official records indicate and it is still spreading to new areas of the state. Poison Hemlock is native to Europe and the Middle East, and it was introduced into North America either accidentally or deliberately.
Habitats include edges of degraded wetlands and prairies, low-lying areas along small rivers, banks of drainage ditches, thickets, woodland borders, fence rows, low-lying areas along railroads and roads, pastures, and abandoned fields. This plant is usually found in disturbed areas, but it occasionally invades native habitats.
Faunal Associations: The nectar of the flowers attracts a wide variety of flies, beetles, sawflies, and wasps, including Ichneumonid and other parasitoid wasps. Caterpillars of the butterfly, Papilio polyxenes asterius (Eastern Black Swallowtail), feed on the foliage, notwithstanding its extreme toxicity (personal observation). This toxicity is the result of the alkaloid coniine and other chemicals, which can be found in all parts of Poison Hemlock, including the seeds and roots. Another insect, Orthops scutellatus (Carrot Plant Bug), eats the seeds of this plant and other members of the Carrot family (Knight, 1941). Poison Hemlock is also a summer host plant of several aphids, including Dysaphis apiifolia (Hawthorn-Parsley Aphid), Hyadaphis foeniculi (Fennel Aphid), and Hyadaphis passerinii (Honeysuckle Aphid); see Blackman & Eastop (2013). Mammalian herbivores won't touch the foliage because of its bitter rank odor and extreme toxicity. Just a small portion of the ingested plant can be fatal to humans.
Comments: The ancient Athenians used the juices of this plant to execute their prisoners, including Socrates during 399 B.C. Death is caused by respiratory arrest and heart failure. Poison Hemlock is a tall and imposing plant that appears to be increasingly common. Many people walk past this species without even realizing what it is. Because there are many members of the Carrot family with small white flowers, it can be somewhat difficult to correctly identify this plant. Poison Hemlock has the following key features: 1) it is often tall-growing, 1) the foliage is at least double pinnate and fern-like in appearance, 2) the foliage has a bitter rank odor, especially when it is bruised, 3) the hairless stems have purple spots, 4) there are undivided bracts at the base of the compound umbel and undivided bractlets at the base of the umbellets, and 5) the small leaflets are pinnately cleft or dentate. Other members of the Carrot family lack one or more of these key features.
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文章
Miss Chen
2018年08月06日
Description: This plant is a summer annual about 1-3' long. It can be erect or sprawl across the ground like a vine. The round stems are smooth and hairless. The hairless alternate leaves are up to 5" long and 2" across. They are ovate, lanceolate-ovate, or slightly cordate. Their margins are smooth and their veins run parallel to each other. The base of each leaf is sessile or clasping, and it has a membranous sheath that wraps around the stem. This sheath is about 1" long and has green longitudinal veins, otherwise it is white or greenish white. The upper edge of the sheath is usually hairless, although it has fine upright hairs for an uncommon variety of this species.
Occasionally, a single flower on a stalk about 1-2" long is produced from the leaf axils. This flower is about ½–1" across, consisting of 2 large blue petals, 1 small white petal, 3 sepals, 5-6 stamens, and a long white style. The sepals are usually pale white and translucent. The upper stamens have showy yellow anthers; they are sterile, but help to attract insects to the flower. The lower stamens are longer than the upper stamens and fertile, although their anthers are less showy. An upturned spathe that lies underneath the flower is green and about 1-2" long. The upper margins of this spathe are free all the way to the base. The blooming period occurs from mid-summer to early fall, and lasts about 1-2 months. Each flower blooms during the morning for a single day, hence the common name. There is no noticeable floral scent. Each flower is replaced by a seed capsule that has 2 cells, each cell containing 2 seeds. These seeds are dark brown or black and have a surface that is bumpy and rough (rugose). The root system is fibrous. This plant can root at the leaf nodes on moist ground, forming new plants vegetatively. At favorable sites, the Asiatic Dayflower forms colonies that can exclude other species of plants.
Cultivation: Partial sun, moist to mesic conditions, and a fertile soil that is loamy or slightly sandy are preferred. This plant also tolerates full sun and light shade. Occasionally, it can spread aggressively and become a pest.
Range & Habitat: The Asiatic Dayflower is a common plant that occurs in most counties of Illinois (see Distribution Map). It appears to be spreading into all areas of the state. Habitats include edges of floodplain forests, thickets, edges of gardens and yards, areas along buildings, fence rows, vacant lots, and waste areas. This plant prefers disturbed areas, although it occasionally invades natural areas. As the common name implies, it was introduced into the United States from East Asia, probably for horticultural purposes.
Faunal Associations: Primarily bees pollinate the flowers. The foliage is eaten by Neolema sexpunctata (Six-Spotted Beetle). Occasionally, the seeds are eaten by upland gamebirds and songbirds, including the Mourning Dove, Bobwhite, and Redwing Blackbird. The foliage of Dayflowers is a preferred food source of the White-Tailed Deer.
Photographic Location: A small colony of Asiatic Dayflower was flourishing between the shrubbery of a commercial bank and a city sidewalk in Urbana, Illinois.
Comments: The flowers of this species have a "true blue" color that is found in few other plants. Usually, most "blue" flowers are closer to violet or purple. The Asiatic Dayflower has become the most common Commelina sp. (Dayflower) in Illinois for reasons that are not entirely clear. Like the native Commelina erecta (Erect Dayflower), its flowers have a small lower petal that is white, whereas the flowers of other Commelina spp. within the state have a lower petal that is blue or violet. The Erect Dayflower differs from the Asiatic Dayflower in a number of characteristics, including the following: 1) It has more narrow leaves than the latter; 2) The upper margins of each upturned spathe are united together about 1/3 the length of the spathe from the base, rather than running free from each other; 3) Each seed capsule has 3 cells containing 1 seed each, rather than 2 cells containing 2 seeds each; 4) It is a more erect plant than the latter; and 5) Its seeds are lighter-colored with a smooth surface, rather than dark and rugose.
Occasionally, a single flower on a stalk about 1-2" long is produced from the leaf axils. This flower is about ½–1" across, consisting of 2 large blue petals, 1 small white petal, 3 sepals, 5-6 stamens, and a long white style. The sepals are usually pale white and translucent. The upper stamens have showy yellow anthers; they are sterile, but help to attract insects to the flower. The lower stamens are longer than the upper stamens and fertile, although their anthers are less showy. An upturned spathe that lies underneath the flower is green and about 1-2" long. The upper margins of this spathe are free all the way to the base. The blooming period occurs from mid-summer to early fall, and lasts about 1-2 months. Each flower blooms during the morning for a single day, hence the common name. There is no noticeable floral scent. Each flower is replaced by a seed capsule that has 2 cells, each cell containing 2 seeds. These seeds are dark brown or black and have a surface that is bumpy and rough (rugose). The root system is fibrous. This plant can root at the leaf nodes on moist ground, forming new plants vegetatively. At favorable sites, the Asiatic Dayflower forms colonies that can exclude other species of plants.
Cultivation: Partial sun, moist to mesic conditions, and a fertile soil that is loamy or slightly sandy are preferred. This plant also tolerates full sun and light shade. Occasionally, it can spread aggressively and become a pest.
Range & Habitat: The Asiatic Dayflower is a common plant that occurs in most counties of Illinois (see Distribution Map). It appears to be spreading into all areas of the state. Habitats include edges of floodplain forests, thickets, edges of gardens and yards, areas along buildings, fence rows, vacant lots, and waste areas. This plant prefers disturbed areas, although it occasionally invades natural areas. As the common name implies, it was introduced into the United States from East Asia, probably for horticultural purposes.
Faunal Associations: Primarily bees pollinate the flowers. The foliage is eaten by Neolema sexpunctata (Six-Spotted Beetle). Occasionally, the seeds are eaten by upland gamebirds and songbirds, including the Mourning Dove, Bobwhite, and Redwing Blackbird. The foliage of Dayflowers is a preferred food source of the White-Tailed Deer.
Photographic Location: A small colony of Asiatic Dayflower was flourishing between the shrubbery of a commercial bank and a city sidewalk in Urbana, Illinois.
Comments: The flowers of this species have a "true blue" color that is found in few other plants. Usually, most "blue" flowers are closer to violet or purple. The Asiatic Dayflower has become the most common Commelina sp. (Dayflower) in Illinois for reasons that are not entirely clear. Like the native Commelina erecta (Erect Dayflower), its flowers have a small lower petal that is white, whereas the flowers of other Commelina spp. within the state have a lower petal that is blue or violet. The Erect Dayflower differs from the Asiatic Dayflower in a number of characteristics, including the following: 1) It has more narrow leaves than the latter; 2) The upper margins of each upturned spathe are united together about 1/3 the length of the spathe from the base, rather than running free from each other; 3) Each seed capsule has 3 cells containing 1 seed each, rather than 2 cells containing 2 seeds each; 4) It is a more erect plant than the latter; and 5) Its seeds are lighter-colored with a smooth surface, rather than dark and rugose.
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文章
Miss Chen
2018年08月05日
The energetic and showy goat's beard perennial (Aruncus dioicus) can fill in a sunny or partially sunny growing location with vibrant foliage and white, fuzzy blossoms. This dense flowering plant may reach heights of up to 6 feet with showy white flowers sitting among the leaves during midsummer. Give this flowering plant basic care, including pruning goat's beard perennial at the proper time, to keep the plant healthy and attractive.
Step 1
Trim the white blossoms after the goat's beard finishes blossoming in the middle of the summer. Use the pruning shears to trim the stems off at the base of the plant. Deadheading the goat's beard keeps the plant neat and may stimulate a second bloom before the end of the growing season.
Step 2
Place the stems into the bucket for disposal. Do not leave the trimmed foliage on the soil around the plant because it may create an unhealthy growing environment for the plant.
Step 3
Cut back the dead growth in the spring before the plant begins growing again. Use the pruning shears to cut the dead growth off just above the soil level. The plant will respond by producing fresh new shoots for the current growing season.
Step 4
Discard the dead growth in a compost bin or the trash.
Step 1
Trim the white blossoms after the goat's beard finishes blossoming in the middle of the summer. Use the pruning shears to trim the stems off at the base of the plant. Deadheading the goat's beard keeps the plant neat and may stimulate a second bloom before the end of the growing season.
Step 2
Place the stems into the bucket for disposal. Do not leave the trimmed foliage on the soil around the plant because it may create an unhealthy growing environment for the plant.
Step 3
Cut back the dead growth in the spring before the plant begins growing again. Use the pruning shears to cut the dead growth off just above the soil level. The plant will respond by producing fresh new shoots for the current growing season.
Step 4
Discard the dead growth in a compost bin or the trash.
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文章
Miss Chen
2018年08月05日
The term "ornamental grass" covers a wide variety of perennial and annual plants with narrow foliage. Perennial types, such as "Gracillimus" Eulalia grass (Miscanthus sinensis "Gracillimus"), which is hardy in U.S. Department of Agriculture plant hardiness zones 6 through 9, can be split and transplanted in either spring or fall to reduce congestion or to create new plants. The timing of grass splitting or division depends on whether the grass is a cool-season variety, which begins new growth in fall, winter or spring, or a warm-season variety, which begins new growth in spring.
Cool-Season Grass Division
Cool-season ornamental grass should be divided in early fall, after the hot summer is gone. Varieties include "Karl Foerster" feather reed grass (Calamagrostis x acutiflora "Karl Foerster"), hardy in USDA zones 5 through 9 and featuring pink-purple flower stalks and an arching habit. Another cool-season ornamental grass is low-growing fescue, such as the "Elijah Blue" cultivar of blue fescue (Festuca glauca "Elijah Blue"). Fescues generally top out at about 12 inches tall. "Elijah Blue" is hardy in USDA zones 4 through 8 and features narrow, blue-green leaves.
Warm-Season Grass Division
Very early spring, when the ground becomes workable but before or just as the grass' new growth starts, is the time to divide a warm-season ornamental grass. Varieties include big blue stem (Andropogon gerardii), which is hardy in USDA zones 4 through 9, tops out at 6 feet tall and changes color as the growing season progresses. Another common warm-season variety is switch grass (Panicum virgatum), a moisture-lover with a columnar form. Switch grass is hardy in USDA zones 5 through 9.
Division and Replant Techniques
Whether division takes place in early spring or early fall, watering the ornamental grass' soil thoroughly about one hour before dividing the plant softens the ground. Cut the plant's foliage to about 6 inches tall. Using a sharp spade, dig all the way around the grass clump, and lift it from the ground. Divide the clump into two or more pieces by using the spade, a sharp garden knife or a small axe to separate roots. One of the pieces can be replanted in the original hole, and other pieces can be planted in other locations. The plants should be at the same soil depth at which they grew previously. Fill the remainder of each planting hole with soil, and firm the soil around the plants.
Division Considerations
Many ornamental grasses, especially large types, should be divided every three or four years. If a clump has not been divided in many years, then its middle portion may be dead. If that is the case, dig up the entire clump, but take divisions from the healthy root areas, discarding the dead middle section. Extremely hot weather makes division hard on a plant and the task of dividing the plant hard on the gardener. If the weather is very hot, wait until temperatures cool before dividing grass.
Cool-Season Grass Division
Cool-season ornamental grass should be divided in early fall, after the hot summer is gone. Varieties include "Karl Foerster" feather reed grass (Calamagrostis x acutiflora "Karl Foerster"), hardy in USDA zones 5 through 9 and featuring pink-purple flower stalks and an arching habit. Another cool-season ornamental grass is low-growing fescue, such as the "Elijah Blue" cultivar of blue fescue (Festuca glauca "Elijah Blue"). Fescues generally top out at about 12 inches tall. "Elijah Blue" is hardy in USDA zones 4 through 8 and features narrow, blue-green leaves.
Warm-Season Grass Division
Very early spring, when the ground becomes workable but before or just as the grass' new growth starts, is the time to divide a warm-season ornamental grass. Varieties include big blue stem (Andropogon gerardii), which is hardy in USDA zones 4 through 9, tops out at 6 feet tall and changes color as the growing season progresses. Another common warm-season variety is switch grass (Panicum virgatum), a moisture-lover with a columnar form. Switch grass is hardy in USDA zones 5 through 9.
Division and Replant Techniques
Whether division takes place in early spring or early fall, watering the ornamental grass' soil thoroughly about one hour before dividing the plant softens the ground. Cut the plant's foliage to about 6 inches tall. Using a sharp spade, dig all the way around the grass clump, and lift it from the ground. Divide the clump into two or more pieces by using the spade, a sharp garden knife or a small axe to separate roots. One of the pieces can be replanted in the original hole, and other pieces can be planted in other locations. The plants should be at the same soil depth at which they grew previously. Fill the remainder of each planting hole with soil, and firm the soil around the plants.
Division Considerations
Many ornamental grasses, especially large types, should be divided every three or four years. If a clump has not been divided in many years, then its middle portion may be dead. If that is the case, dig up the entire clump, but take divisions from the healthy root areas, discarding the dead middle section. Extremely hot weather makes division hard on a plant and the task of dividing the plant hard on the gardener. If the weather is very hot, wait until temperatures cool before dividing grass.
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