文章
Miss Chen
2018年03月27日
Description: This biennial wildflower forms a low rosette of leaves about 8-12" across during the first year. During the second year, it bolts and becomes 2-7' tall. Usually, this wildflower is unbranched, although sometimes ascending lateral branches develop along the upper one-third of a large plant. The central stem (and any lateral stems) is rather stout, terete, and light green to pale purple; it is usually hairy along the lower half of its length, becoming hairless and slightly glaucous along the upper half. The alternate leaves are up to 6" long and 2" across, becoming gradually smaller as they ascend the stem; they are pinnatifid with pointed irregular lobes and dentate along their margins. The upper surfaces of these leaves are medium green and often sparsely hairy; their lower surfaces are pale green and hairy, particularly along the midribs.
The basal leaves are similar to the alternate leaves, except they tend to be larger in size and more wide toward their tips (narrowly obovate to obovate). Young developing basal leaves are usually very hairy on both their upper and lower surfaces. The central stem (and any lateral stems) terminates in an elongated panicle of flowerheads about 6-12" long and 2-4" across. The branches of the panicle are light green to reddish purple, terete, and usually hairless. Each flowerhead is about 1/3" (8-10 mm.) across when fully open, consisting of 12-25 ray florets, no disk florets, and light green to purple floral bracts that are arranged in about 3 series around its base (involucre); this base is about 2/3–3/4" (15-20 mm.) long. The rays of the flowerhead are colored salmon to brick-red and their tips are truncate and finely toothed. The outer floral bracts are shorter than the inner floral bracts.
The blooming period occurs from mid-summer to early fall and usually lasts about 3 weeks. Individual flowerheads last only a single day, blooming for only a few hours on sunny days. After only a short period of time, individual flowerheads are replaced by small black achenes with tufts of white hair. Each achene is 4-5 mm. long, ellipsoid-oblanceoloid in shape, and flattened; the tuft of white hairs is attached to the achene by a slender white beak about 2.5–3.5 mm. long. These achenes are distributed by the wind. The root system consists of a taproot. This wildflower reproduces by reseeding itself.
Cultivation: The preference is partial sun, mesic to dry conditions, and somewhat acidic sandy or rocky soil. The size of individual plants is highly variable, depending on moisture levels and soil fertility.
Range & Habitat: Red-Flowered Wild Lettuce is a rare native plant in Illinois and it is state-listed as 'endangered.' Thus far, this species has been collected from a single county in southern Illinois (see Distribution Map). Because this species can be confused with other Lactuca spp., it may occur in other areas of the state. Outside of Illinois, this species is also uncommon. Habitats include upland rocky woodlands, woodland openings, woodland borders, upland savannas, sandstone glades, pastures, and abandoned fields. These habitats also include sandy areas. Red-Flowered Wild Lettuce prefers some disturbance to reduce the abundance of woody vegetation.
Faunal Associations: Little is known about floral-faunal relationships for this particular species. The flowerheads are probably cross-pollinated by various bees (medium- to small-sized), which offer nectar and pollen. In general, the caterpillars of some moths feed on Lactuca spp. (Wild Lettuce species), including Autographa precationis (Common Looper Moth), Grammia virgo (Virgin Tiger Moth), and Cucullia intermedia (Intermediate Cucullia). The caterpillars of the last moth species feed on the flowerheads. Other insect feeders include Thrips physapus (Dandelion Thrips) and several aphid species: Hyperomyza lactucae (Currant-Sowthistle Aphid), Nasonovia ribisnigri (Currant-Lettuce Aphid), Pemphigus bursarius (Lettuce Root Aphid), Prociphilus erigeronensis (White Aster Root Aphid), Uroleucon ambrosiae (Brown Ambrosia Aphid), Uroleucon gravicorne (Aphid sp.), Uroleucon pseudambrosiae (False Ambrosia Aphid), Uroleucon rudbeckiae (Golden Glow Aphid), and Uroleucon sonchella (Sowthistle Aphid). Among vertebrate animals, the Eastern Goldfinch eats the seeds, while White-Tailed Deer occasionally graze on the foliage of Lactuca spp.
Photographic Location: The wildflower garden of the webmaster in Urbana, Illinois.
Comments: This unusual species has been sadly neglected from many wildflower field guides. Although it has an extensive range in the eastern half of the United States, Red-Flowered Wild Lettuce appears to be uncommon to rare in most areas. The preceding description applies to var. sanguinea, rather the typical variety. In other areas of its range, Lactuca hirsuta may have yellow flowerheads and the hairiness of its stems and leaves can be variable (from nearly hairless to very hairy). Red-Flowered Wild Lettuce can be easily confused with the more common Lactuca canadensis (Common Wild Lettuce), which is itself a rather variable species. Generally, Common Wild Lettuce has flowerheads that are pale yellow to dull orange, flowerheads with shorter bases (involucres) that are ½" or less, and shorter achenes (less than 4 mm. long). Common Wild Lettuce is usually completely glabrous (except for some hairs along the lower midribs of its leaves), and its upper stems and floral branches are usually less purple. Another species, Lactuca biennis (Tall Blue Lettuce), has light blue to cream-colored flowerheads and its achenes have shorter beaks and tufts of tawny or gray hair, rather than white hair. These different Lactuca spp. cannot be identified reliably unless the flowerheads or tufted achenes are available for examination. Another common name of Lactuca hirsuta is Hairy Wild Lettuce.
The basal leaves are similar to the alternate leaves, except they tend to be larger in size and more wide toward their tips (narrowly obovate to obovate). Young developing basal leaves are usually very hairy on both their upper and lower surfaces. The central stem (and any lateral stems) terminates in an elongated panicle of flowerheads about 6-12" long and 2-4" across. The branches of the panicle are light green to reddish purple, terete, and usually hairless. Each flowerhead is about 1/3" (8-10 mm.) across when fully open, consisting of 12-25 ray florets, no disk florets, and light green to purple floral bracts that are arranged in about 3 series around its base (involucre); this base is about 2/3–3/4" (15-20 mm.) long. The rays of the flowerhead are colored salmon to brick-red and their tips are truncate and finely toothed. The outer floral bracts are shorter than the inner floral bracts.
The blooming period occurs from mid-summer to early fall and usually lasts about 3 weeks. Individual flowerheads last only a single day, blooming for only a few hours on sunny days. After only a short period of time, individual flowerheads are replaced by small black achenes with tufts of white hair. Each achene is 4-5 mm. long, ellipsoid-oblanceoloid in shape, and flattened; the tuft of white hairs is attached to the achene by a slender white beak about 2.5–3.5 mm. long. These achenes are distributed by the wind. The root system consists of a taproot. This wildflower reproduces by reseeding itself.
Cultivation: The preference is partial sun, mesic to dry conditions, and somewhat acidic sandy or rocky soil. The size of individual plants is highly variable, depending on moisture levels and soil fertility.
Range & Habitat: Red-Flowered Wild Lettuce is a rare native plant in Illinois and it is state-listed as 'endangered.' Thus far, this species has been collected from a single county in southern Illinois (see Distribution Map). Because this species can be confused with other Lactuca spp., it may occur in other areas of the state. Outside of Illinois, this species is also uncommon. Habitats include upland rocky woodlands, woodland openings, woodland borders, upland savannas, sandstone glades, pastures, and abandoned fields. These habitats also include sandy areas. Red-Flowered Wild Lettuce prefers some disturbance to reduce the abundance of woody vegetation.
Faunal Associations: Little is known about floral-faunal relationships for this particular species. The flowerheads are probably cross-pollinated by various bees (medium- to small-sized), which offer nectar and pollen. In general, the caterpillars of some moths feed on Lactuca spp. (Wild Lettuce species), including Autographa precationis (Common Looper Moth), Grammia virgo (Virgin Tiger Moth), and Cucullia intermedia (Intermediate Cucullia). The caterpillars of the last moth species feed on the flowerheads. Other insect feeders include Thrips physapus (Dandelion Thrips) and several aphid species: Hyperomyza lactucae (Currant-Sowthistle Aphid), Nasonovia ribisnigri (Currant-Lettuce Aphid), Pemphigus bursarius (Lettuce Root Aphid), Prociphilus erigeronensis (White Aster Root Aphid), Uroleucon ambrosiae (Brown Ambrosia Aphid), Uroleucon gravicorne (Aphid sp.), Uroleucon pseudambrosiae (False Ambrosia Aphid), Uroleucon rudbeckiae (Golden Glow Aphid), and Uroleucon sonchella (Sowthistle Aphid). Among vertebrate animals, the Eastern Goldfinch eats the seeds, while White-Tailed Deer occasionally graze on the foliage of Lactuca spp.
Photographic Location: The wildflower garden of the webmaster in Urbana, Illinois.
Comments: This unusual species has been sadly neglected from many wildflower field guides. Although it has an extensive range in the eastern half of the United States, Red-Flowered Wild Lettuce appears to be uncommon to rare in most areas. The preceding description applies to var. sanguinea, rather the typical variety. In other areas of its range, Lactuca hirsuta may have yellow flowerheads and the hairiness of its stems and leaves can be variable (from nearly hairless to very hairy). Red-Flowered Wild Lettuce can be easily confused with the more common Lactuca canadensis (Common Wild Lettuce), which is itself a rather variable species. Generally, Common Wild Lettuce has flowerheads that are pale yellow to dull orange, flowerheads with shorter bases (involucres) that are ½" or less, and shorter achenes (less than 4 mm. long). Common Wild Lettuce is usually completely glabrous (except for some hairs along the lower midribs of its leaves), and its upper stems and floral branches are usually less purple. Another species, Lactuca biennis (Tall Blue Lettuce), has light blue to cream-colored flowerheads and its achenes have shorter beaks and tufts of tawny or gray hair, rather than white hair. These different Lactuca spp. cannot be identified reliably unless the flowerheads or tufted achenes are available for examination. Another common name of Lactuca hirsuta is Hairy Wild Lettuce.
0
0
文章
Miss Chen
2018年03月08日
Description: This herbaceous plant is a summer annual about 2-6' tall. It branches regularly from the central stem, while the side stems branch very little. These stems are somewhat pubescent and green to reddish green. The opposite leaves are up to 12" and 4" across, becoming smaller as they ascend the stems. The lower leaves are pinnately lobed, cleft, and coarsely toothed, while the upper leaves are lanceolate-oblong and smooth along the margins. The petioles of the leaves become progressively shorter toward the apex of the plant; the upper leaves are often sessile. Both lower and upper leaves are hairless, or nearly so.
The upper stems terminate in spike-like racemes of yellow flowers. These racemes vary ½–3' in length, depending on the size of the plant. Each flower is about ½" long, consisting of a yellow tubular corolla with 5 spreading lobes and a green calyx with 5 blunt teeth. The tubular corolla is rather short and broad; its throat is partially obstructed by an abundance of fine yellow hairs. The two upper lobes of the corolla fold backward, while the 3 lower lobes function as a landing pad for visiting insects. The blooming period is mid-summer to early fall and lasts about 1½ months; only a few flowers are in bloom at the same time. Each flower is replaced by a seed capsule is globoid-ovoid; it eventually turns brown and contains several seeds. The root system consists of a taproot and secondary feeder roots. The feeder roots can attach themselves to the roots of oak trees; they suck moisture and possibly some nutrients from the host tree. Thus, Mullein Foxglove is partially parasitic. Reproduction is by seed.
Cultivation: The preference is partial sun, mesic to dry conditions, and a loam, clay-loam, or rocky soil. This plant benefits from the proximity of oak trees. Its size is highly variable, depending on growing conditions.
Range & Habitat: The native Mullein Foxglove occurs occasionally throughout most of Illinois; it is least common in the NW and south-central areas of the state (see Distribution Map). Habitats include open rocky woodlands, oak savannas, paths through woodlands, thinly wooded bluffs, woodland borders, thickets, and rocky slopes along rivers. This species tolerates low to moderate levels of disturbance.
Faunal Associations: The most important pollinators of the flowers are bumblebees, which suck nectar and collect pollen. Other long-tongued bees also visit the flowers, including honeybees and Miner bees. Occasionally, butterflies and skippers suck nectar from the flowers, but they are ineffective pollinators. The caterpillars of the moth Rhodoecia aurantiago (Orange Sallow) bore into the seed capsules and feed on the seeds. It possible that the foliage is eaten by the caterpillars of the butterflies Junonia coenia (Buckeye) and Euphydryas phaeton ozarkae (Baltimore). The latter variety of the Baltimore is confined to southern Illinois. Both of these butterfly species are known to feed on the foliage of Aureolaria spp. (False Foxgloves), which are closely related to Mullein Foxglove.
Photographic Location: Along a path at Busey Woods in Urbana, Illinois.
Comments: This annual plant can achieve an impressive size. It closely resembles several Aureolaria spp. (False Foxgloves), which are also parasitic on the roots of oaks. The flowers of Mullein Foxglove are a little shorter than the flowers of the latter species (which can exceed ¾" in length), and the throat of its flowers are partially obstructed by an abundance of fine hairs. The flowers of the False Foxgloves are quite open at the throat because they lack these hairs. Another scientific name for Mullein Foxglove is Seymeria macrophylla.
The upper stems terminate in spike-like racemes of yellow flowers. These racemes vary ½–3' in length, depending on the size of the plant. Each flower is about ½" long, consisting of a yellow tubular corolla with 5 spreading lobes and a green calyx with 5 blunt teeth. The tubular corolla is rather short and broad; its throat is partially obstructed by an abundance of fine yellow hairs. The two upper lobes of the corolla fold backward, while the 3 lower lobes function as a landing pad for visiting insects. The blooming period is mid-summer to early fall and lasts about 1½ months; only a few flowers are in bloom at the same time. Each flower is replaced by a seed capsule is globoid-ovoid; it eventually turns brown and contains several seeds. The root system consists of a taproot and secondary feeder roots. The feeder roots can attach themselves to the roots of oak trees; they suck moisture and possibly some nutrients from the host tree. Thus, Mullein Foxglove is partially parasitic. Reproduction is by seed.
Cultivation: The preference is partial sun, mesic to dry conditions, and a loam, clay-loam, or rocky soil. This plant benefits from the proximity of oak trees. Its size is highly variable, depending on growing conditions.
Range & Habitat: The native Mullein Foxglove occurs occasionally throughout most of Illinois; it is least common in the NW and south-central areas of the state (see Distribution Map). Habitats include open rocky woodlands, oak savannas, paths through woodlands, thinly wooded bluffs, woodland borders, thickets, and rocky slopes along rivers. This species tolerates low to moderate levels of disturbance.
Faunal Associations: The most important pollinators of the flowers are bumblebees, which suck nectar and collect pollen. Other long-tongued bees also visit the flowers, including honeybees and Miner bees. Occasionally, butterflies and skippers suck nectar from the flowers, but they are ineffective pollinators. The caterpillars of the moth Rhodoecia aurantiago (Orange Sallow) bore into the seed capsules and feed on the seeds. It possible that the foliage is eaten by the caterpillars of the butterflies Junonia coenia (Buckeye) and Euphydryas phaeton ozarkae (Baltimore). The latter variety of the Baltimore is confined to southern Illinois. Both of these butterfly species are known to feed on the foliage of Aureolaria spp. (False Foxgloves), which are closely related to Mullein Foxglove.
Photographic Location: Along a path at Busey Woods in Urbana, Illinois.
Comments: This annual plant can achieve an impressive size. It closely resembles several Aureolaria spp. (False Foxgloves), which are also parasitic on the roots of oaks. The flowers of Mullein Foxglove are a little shorter than the flowers of the latter species (which can exceed ¾" in length), and the throat of its flowers are partially obstructed by an abundance of fine hairs. The flowers of the False Foxgloves are quite open at the throat because they lack these hairs. Another scientific name for Mullein Foxglove is Seymeria macrophylla.
0
0
