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Miss Chen
2018年03月27日
Miss Chen
Description: This perennial wildflower is 1-3½' tall, producing a leafy central stem that is unbranched and more or less erect. The central stem is light green and more or less covered with spreading hairs; some hairs along the upper section of this stem may be glandular, otherwise they are non-glandular. Several alternate leaves occur along the lower three-fourths of this stem, becoming gradually smaller in size and more widely spaced as they ascend toward the inflorescence. The leaf blades are 2-6" long and ½-2" across, lanceolate-oblanceolate to ovate-obovate with smooth to nearly smooth margins. Some larger leaves may have widely spaced dentate teeth that are poorly defined. The upper surface of the leaf blades is medium green and hairy, while the lower surface is pale green and hairy. Each leaf tapers gradually into a petiole-like base and its tip is relatively blunt. Both the central stem and leaves contain a milky latex.
The central stem terminates in an elongated panicle of flowerheads up to 1' long and ½' across. Individual flowerheads are ½-¾" across, consisting of 30-60 yellow ray florets and no disk florets. Around the base of each flowerhead, 12-20 floral bracts (phyllaries) are arranged in a single series. Individual floral bracts are light green, linear in shape, and often glandular-hairy. The branches of the inflorescence are light green to dull purple and glandular-hairy; there are often a small leafy bracts (less than 1" in length) where these branches divide. The glandular hairs along the branches of the inflorescence and the floral bracts of the flowerheads are often black. The blooming period occurs from late summer to early fall for about 3-4 weeks. The florets are self-fertile in the absence of cross-pollination. The florets are replaced by achenes with tufts of tawny hair. Individual mature achenes are about 1/8" (3 mm.) long, narrowly cylindrical in shape, truncate at the apex, and dark brown. The root system is fibrous and rhizomatous; older plants may have a short underground caudex. Small colonies of plants are formed occasionally by the spreading rhizomes. A small rosette of basal leaves may be present during the winter after the flowering stalk with alternate leaves dies down. Stem & LeavesCultivation: The preference is full sun to light shade, mesic to dry-mesic conditions, and soil containing loam, sand, or rocky material. The size of individual plants and the abundance of their flowerheads is highly variable. Range & Habitat: The native Rough Hawkweed is occasional in most areas of Illinois (see Distribution Map). Habitats include rocky upland woodlands, bluffs, wooded slopes, woodland openings, savannas and sandy savannas, partially shaded ledges, woodland borders, and sandy roadsides. This wildflower benefits from occasional disturbance to reduce competition from woody vines, shrubs, and trees. Faunal Associations: Surprisingly little information is available for hawkweeds (Hieracium spp.) about their floral-faunal relationships. The flowerheads are probably cross-pollinated by long-tongued bees and other insects; both nectar and pollen are available as floral rewards to such visitors. Hawkweeds are suspected host plants for the caterpillars of Schinia bina (Bina Flower Moth). The seeds or leaves are occasionally eaten by the Wild Turkey and Ruffed Grouse, while the foliage is browsed sparingly by the Cottontail Rabbit and White-Tailed Deer (Martin et al., 1951/1961). However, the bitter white latex and hairiness of the foliage does not make this species a preferred source of food for such animals. Photographic Location: A deciduous woodland near an artificial lake at a state park in east-central Illinois. Comments: This is one of several native hawkweeds (Hieracium spp.) in Illinois that have unbranched leafy stems and yellow flowerheads. Generally, they prefer semi-shaded wooded areas that are sandy or rocky, although Rough Hawkweed also occurs in woodlands with fertile loam. It is very similar in appearance to Hieracium gronovii (Gronovius' Hawkweed), but the latter species has spindle-shaped achenes with tapered upper tips (rather than truncate upper tips), relatively fewer florets per flowerhead (about 20-40), and leaves that are located toward the base of its central stem. Another similar species, Hieracium canadense (Canada Hawkweed), has larger flowerheads (¾-1¼" across) with more florets per flowerhead (40-100), inflorescence branches that are short-pubescent (rather than glandular-hairy), and more leaves along each central stem (often 12 or more). There are some hawkweeds that have been introduced from Europe, but their leaves are arranged in basal rosettes during the blooming period, unlike the native hawkweed species.
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Miss Chen
2018年03月27日
Miss Chen
Description: This perennial herbaceous wildflower is 3–6½' tall, sending up one or more erect leafy stems from its root system. The stems are light green, faded light yellow, or faded light brown; they are terete, stiffly short-pubescent, and sparingly branched above. Most of the leaves are located along the lower half of the primary stems, where they are opposite. Smaller alternate leaves occur sparingly along the upper primary and secondary stems. All of these stems are erect to ascending. The lower to middle leaves are up to 6" long and 5" across; they are broadly oblong to oval-ovate in shape with margins that are slightly serrated to doubly serrated. To a limited extent, the leaf margins are also horizontally undulate. The leaves abruptly contract to narrowly winged petioles up to 2" long. These petioles have short stiff hairs. The leaf blades are medium green or yellowish green above, and light green below. The upper blade surface is sparsely covered with minute stiff hairs, providing it with a rough texture. The lower blade surface has short stiff hairs along the primary veins and a sparse covering of minute stiff hairs between the veins. The leaves have a prominent central vein and two prominent lateral veins; the latter curve toward the leaf tips.
The upper stems terminate in either solitary flowerheads or small loose clusters of 2-3 flowerheads on long naked peduncles up to 1' long. These flowerheads tend to occur at different heights from the ground. The peduncles are similar to the stems, except they are a little more narrow in diameter. The flowerheads are held erect or at an angle facing partly upward; they span about 2-3" across. Each flowerhead has 10-20 ray florets and a central disk of numerous disk florets. The widely spreading petaloid rays are bright yellow and oblong in shape. The corollas of the disk florets are about 6 mm. (¼") long, tubular in shape with 5 upper lobes, and dark red above. The divided styles of the disk florets are bright yellow, while their tubular anthers are dark red. The ray florets are sterile, while the disk florets are perfect. Surrounding the base of each flowerhead, there are floral bracts (phyllaries) in 3 series; these bracts differ in size and they are appressed together. Individual floral bracts are light green and broadly oblong in shape; their tips are obtusely pointed or rounded. The margins of these bracts are toothless and ciliate; their outer surfaces between the margins are sparsely short-pubescent. The blooming period occurs during early autumn, lasting about 3-4 weeks. Afterwards, fertile disk florets are replaced achenes about 4 mm. in length. These achenes are oblong-obovate, somewhat flattened, brown, and short-pubescent primarily toward their apices. Each achene has a pair of lanceolate scales about 2 mm. long at its apex. However, these scales are early-deciduous. Because the seeds are dispersed primarily by gravity, they usually do not travel far from the mother plant. The root system consists of a crown of fibrous roots and short rhizomes. Clonal offsets are produced sparingly from the short rhizomes. Cultivation: This plant prefers full or partial sun and mesic to dry-mesic conditions; it adapts to different soil types, including those that contain sand, loam, clay, and rocky material. It is easy to cultivate this plant in gardens and it remains more or less erect, rather than flopping over. Because of its short rhizomes, it is a less aggressive spreader than some sunflower species.
Range & Habitat: Silphium Sunflower has been found in only 2 counties of southern Illinois (Alexander and St. Clair counties), where it is native and rare (see Distribution Map). It may be extirpated from Alexander county, but several populations of this plant still persist in St. Clair county. Illinois lies along the northern range-limit of this species. Silphium Sunflower is endemic to south-central and central United States, where it is found primarily in Arkansas, Missouri, and Tennessee. Habitats include sand prairies, upland prairies and glades, upland savannas, openings in rocky woodlands, low sandy ground along streams, roadsides, and fallow fields. This sunflower is found in both high quality natural areas and disturbed sites. In wooded habitats, it benefits from occasional wildfires. Destruction of habitat by development and invasion of exotic species are the primary threats to this rare plant in Illinois (Molano-Flores, 2004).
Faunal Association: While little is known about floral-faunal relationships for this particular sunflower species, considerable information is available about other sunflower species and sunflowers in general. Similar species of sunflowers attract such flower-visiting insects as bumblebees, long-horned bees (Melissodes spp.), leaf-cutter bees (Megachile spp.), Halictid bees (Agapostemon spp., Lasioglossum spp.), Andrenid bees (Andrena spp.), dagger bees (Heterosarus spp.), plasterer bees (Colletes spp.), cuckoo bees (Epeolus spp., Triepeolus spp.), miscellaneous wasps, Syrphid flies (Eristalis spp., Toxomerus spp.), bee flies (Exoprosopa spp.), miscellaneous butterflies, and miscellaneous skippers (Robertson, 1929, and others). Some bees are specialist pollinators (oligoleges) of sunflowers; they include Melissodes agilis, Dufourea marginata, Andrena accepta, Andrena aliciae, Andrena helianthi, and Pseudopanurgus rugosus. Other insects feed destructively on the leaves, stems, roots, seeds, and florets of sunflowers. These species include weevils, long-horned beetles, leaf beetles, billbugs, seed weevils, larvae of leaf-miner flies, larvae of gall midges, plant bugs, aphids, treehoppers, mealybugs, larvae of Tortricid moths, larvae of Noctuid moths, larvae of other moths, grasshoppers, and flower thrips. The caterpillars of some butterflies feed on sunflowers; these species include Chlosyne gorgone (Gorgon Checkerspot), Chlosyne nycteis (Silvery Checkerspot), and Vanessa cardui (Painted Lady); see Bouseman & Sternburg, 2001; Charlet & Gavloski, 2011. Some vertebrate animals use sunflowers as a source of food. Upland gamebirds and songbirds eat their nutritious seeds; the Mourning Dove, Bobwhite Quail, American Crow, Eastern Goldfinch, Common Grackle, Eastern Meadowlark, White-breasted Nuthatch, and various sparrows are examples of such birds (Lewis, 1993; Martin et al., 1951/1961). White-tailed Deer and domesticated grazing animals like to feed on the young stems and leaves of these plants (Georgia, 1913; Martin et al., 1951/1961). The seeds of sunflowers are dispersed to a limited extent by birds; sometimes they drop the seeds during flight before they consume them.
Photographic Location: The wildflower garden of the webmaster in Urbana, Illinois. Comments: The Silphium Sunflower (Helianthus silphioides) is often overlooked in wildflower guidebooks and it is little-known by members of the public. This is partly because, for a long time, this sunflower was considered a variety of the Purple-disk Sunflower (Helianthus atrorubens). However, the Silphium Sunflower differs from the latter by having fewer long hairs on its stems, more narrow and less winged petioles, and achenes that are pubescent primarily toward their apices, rather than throughout. The Purple-disk Sunflower is found primarily in SE United States; it does not occur in Illinois. Scientific synonyms of the Silphium Sunflower include Helianthus atrorubens pubescens and Helianthus kentuckiensis. Other common names of this sunflower include Rosinweed Sunflower and Ozark Sunflower. The common names, Silphium Sunflower and Rosinweed Sunflower, refer to the superficial similarity of this sunflower to the prairie wildflower, Silphium integrifolium (Rosinweed). It also resembles Heliopsis helianthoides (False Sunflower) to a significant extent, but the flowerheads of Silphium Sunflower are borne on longer naked stalks than those of the False Sunflower, and it usually blooms later in the year than the latter species.
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Miss Chen
2018年03月26日
Miss Chen
Description: This perennial wildflower is 2½-5' tall and unbranched, except where the flowerheads occur. The central stem is light green to reddish purple, terete, and more or less covered with either short stiff hairs or longer bristly hairs. Pairs of opposite leaves occur along the central stem; each pair of leaves rotates 90° from an adjacent pair of leaves. There may be 1-2 smaller alternate leaves along the top of the central stem, or along upper lateral stems, underneath the flowerheads. Leaf blades are 2½-6" long and ½-2½" across; they are narrowly lanceolate to ovate in shape and serrated to nearly toothless along their margins. The upper surface of the leaf blades is medium green and rough-textured from minute stiff hairs, while the lower surface is pale green and more or less pubescent. The short petioles are usually ¼-½" long. The central stem and any lateral stems terminate in flowerheads on erect to ascending peduncles (flowering stalks) about 1-4" long. These peduncles have characteristics that are similar to the central stem. Individual flowerheads are 2-3" across, consisting of 10-15 ray florets that surround numerous disk florets. The ray florets have petal-like corollas that are yellow; they are sterile. The disk florets have yellow tubular corollas that are perfect and fertile; they are 5-lobed along their upper rims. Around the base of each flowerhead, there are light green phyllaries (floral bracts) in 3-4 overlapping series; they are narrowly lanceolate to lanceolate in shape and slightly ciliate. When the flowerheads bloom, the phyllaries are ascending to widely spreading. The blooming period occurs from mid-summer to early fall for about 2 months. Afterwards, the disk florets are replaced by achenes about 4 mm. long that are narrowly ovoid, somewhat flattened, and glabrous (hairless). Each achene has a pair of tiny chaffy scales at its apex that become detached easily. The root system is fibrous and long-rhizomatous. This wildflower often forms colonies of plants from the rhizomes. Distribution Map Cultivation: The preference is full or partial sun, mesic to dry conditions, and soil that contains clay-loam, loam, rocky material, or sand. Hairy Sunflower is easy to grow, but it may spread aggressively in some situations. Range & Habitat: The native Hairy Sunflower is occasional throughout Illinois. Habitats include thinly wooded bluffs, upland savannas, borders of upland woodlands, black soil prairies, sand prairies, limestone glades, areas along railroads, and abandoned fields. In upland areas with woody vegetation, this wildflower is often associated with oak trees. It is found in both disturbed and higher quality habitats. Faunal Associations: The nectar and pollen of Hairy Sunflower and other sunflowers attract a wide variety of insects, including long-tongued bees (honeybees, bumblebees, leaf-cutting bees, miner bees, cuckoo bees), short-tongued bees (Halictid bees & Andrenid bees), miscellaneous wasps, flies (Syrphid flies, bee flies, thick-headed flies, & others), butterflies and skippers, and occasional beetles. Several bees are specialist pollinators (oligoleges) of sunflowers: Andrena accepta, Andrena aliciae, Andrena helianthi, Dufourea marginatus, Melissodes agilis, and Pseudopanurgus rugosus. Other insects feed more destructively on the leaves, stems, flowerheads, plant juices, or roots. These species include caterpillars of the butterflies Chlosyne gorgone (Gorgon Checkerspot), Chlosyne nycteis (Silvery Checkerspot), and Vanessa cardui (Painted Lady); they also include caterpillars of the moths Dichomeris flavocostella (Cream-Bordered Dichomeris), Ogdoconta cinereola (Common Pinkband), and others (see Moth Table). Other insect feeders include Aphis helianthi (Sunflower Aphid) and other aphids, several treehoppers and leafhoppers, Clastoptera xanthocephala (Sunflower Spittlebug), the plant bugs Ilnacora stalii and Plagiognathus nigronitens, the thrips Heterothrips auranticornis, the larvae of Apion occidentale (Black Sunflower Stem Weevil) and other weevils, the leaf beetles Exema dispar and Sumitrosis inaequalis, Euphoria inda (Bumble Flower Beetle), the larvae of Contarinia schulzi (Sunflower Midge), and several grasshoppers (see the Insect Table for a more complete list of species).
The nutritious seeds of Hairy Sunflower and other sunflowers are eaten by the Bobwhite, Mourning Dove, Eastern Goldfinch, Tufted Titmouse, Harris Sparrow, White-Throated Sparrow, and other birds. The seeds are also eaten by some mammals, including the Gray Squirrel, Thirteen-Lined Ground Squirrel, Prairie Vole, and White-Footed Mouse. The Plains Pocket Gopher eats the rhizomes of sunflowers, while the White-Tailed Deer, Cottontail Rabbit, and Groundhog feed on the foliage. Because sunflowers are tall leafy plants that often form colonies, they provide good ground cover for many kinds of wildlife. Photographic Location: A wildflower garden at Crystal Lake Park in Urbana, Illinois. The photographed plant is Helianthus hirsutus trachyphyllus.
Comments: Because Hairy Sunflower is rather variable across local populations in Illinois and elsewhere, three different varieties have been described: the typical variety, var. trachyphyllus, and var. stenophyllus. The typical variety has long bristly hairs along its stems and its leaves are usually 1-2½" across; var. trachyphyllus has short stiff hairs along its stems and its leaves are usually 1-2½" across; and var. stenophyllus has leaves that are only ½-1" across. The distribution map of Hairy Sunflower does not distinguish between these different varieties. Other sunflower species that Hairy Sunflower can be confused with include Helianthus pauciflorus (Prairie Sunflower), Helianthus strumosus (Pale-Leaved Sunflower), and Helianthus tuberosus (Jerusalem Artichoke). Prairie Sunflower resembles the narrow-leaved variety of Hairy Sunflower (Helianthus hirsutus stenophyllus), but its disk florets are dark purple or maroon, rather than yellow; Prairie Sunflower also has wider phyllaries (floral bracts) that are deltate-ovate in shape. Pale-Leaved Sunflower differs from Hairy Sunflower by its smooth (or nearly smooth) stems and its tends to have slightly longer petioles (½-1" long); also the undersides of its leaf blades are less hairy than those of Hairy Sunflower. The Jerusalem Artichoke differs by having slightly wider leaves with longer petioles (1-2½" long); it also has more alternate leaves along its stems. There is no dominant common name for Helianthus hirsutus. In addition to Hairy Sunflower, this species is also referred to as the Bristly Sunflower, Rough Sunflower, Oblong Sunflower, and Stiff-Haired Sunflower!
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Miss Chen
2018年03月26日
Miss Chen
Description: This perennial wildflower is 2½-6' tall with a central stem that becomes branched where the flowerheads occur. This stem is light green to dark purple, slender, terete (round in cross-section), glabrous to sparsely covered with short stiff hairs, and sometimes glaucous. Upper secondary stems have similar characteristics. Pairs of widely spreading opposite leaves occur along the central stem and any secondary stems; each pair of leaves rotates 90° from the pair of leaves below. Leaf blades are 2-6" long and ½-2" across; they are lanceolate-oblong to ovate-oblong in shape, and either toothless or with widely spaced teeth along their short-ciliate margins. The base of each leaf blade is rounded-truncate, while its tip is long and gradually tapering. The upper surface of the leaf blades is yellowish green to medium green and sparsely to moderately covered with short stiff hairs, while the pale lower surface is short-pubescent, especially along the major veins. Three prominent veins join together at the base of each leaf blade. The leaves are sessile or they have short ascending petioles (up to 1/8" or 3 mm. long). The central and secondary stems terminate in flowerheads on slender peduncles. Individual flowerheads are 1½-3" across, consisting of 8-15 ray florets that surround numerous disk florets. The yellow corollas of the ray florets are petal-like and widely spreading.. The yellow corollas of the disk florets are narrowly tubular (less than 1/8" or 3 mm. long) with 5 spreading lobes. At the base of each flowerhead, there are light green phyllaries (floral bracts) that are arranged in several overlapping series. Individual phyllaries are linear-lanceolate and ciliate along their margins; the outer phyllaries are widely spreading or recurved when the flowerheads bloom. The peduncles of the flowerheads resemble the stems, except they are more likely to have short stiff hairs. The blooming period occurs from mid-summer to early fall for about 2 months. Afterwards, the disk florets are replaced by achenes about 2 mm. long; these achenes are ovoid-oblongoid and somewhat flattened. At the apex of each achene, there is a pair of tiny chaffy scales that easily become detached. The root system is long-rhizomatous. Vegetative colonies of plants are often formed by the rhizomes. Cultivation: The preference is full or partial sun, moist to dry-mesic conditions, and soil that is loamy, sandy, or rocky. This wildflower is easy to cultivate, although it may spread aggressively. Distribution MapRange & Habitat: The native Woodland Sunflower is common in NE and SE Illinois, while in the rest of the state it is occasional. Habitats include upland rocky woodlands, sandy woodlands, thinly wooded bluffs, upland savannas and sandy savannas, woodland borders, sandy and non-sandy thickets, limestone glades, hill prairies, and moist to dry-mesic sand prairies. While this sunflower is normally found in relatively dry upland habitats, sometimes it also occurs in moist sandy habitats. Occasional wildfires tend to increase populations of Woodland Sunflower as this reduces competition from woody vegetation. Faunal Associations: The nectar and pollen of the flowers attract a wide variety of insects. The following bees are specialist pollinators (oligoleges) of Woodland Sunflower and other sunflowers: Andrena accepta, Andrena aliciae, Andrena helianthi, Dufourea marginatus, Melissodes agilis, and Pseudopanurgus rugosus. Other floral visitors include long-tongued bees (honeybees, bumblebees, digger bees, leaf-cutting bees, cuckoo bees, etc.), short-tongued bees (Halictid bees and Andrenid bees), miscellaneous wasps, miscellaneous flies (Syrphid flies, bee flies, thick-headed flies, etc.), butterflies and skippers, and Chauliognathus pennsylvanicus (Goldenrod Soldier Beetle). Other insects feed on the foliage, bore through the stems, suck plant juices, etc., from sunflowers. These species include caterpillars of the butterflies Chlosyne nycteis (Silvery Checkerspot), Chlosyne gorgone (Gorgon Checkerspot), and Vanessa cardui (Painted Lady); the caterpillars of Cochylis hospes (Banded Sunflower Moth), Papaipema necopina (Sunflower Borer Moth), Stiria rugifrons (Sunflower Seed Copper), and other moths also feed on these wildflowers (see Moth Table). Sunflowers are important host plants for many aphids, treehoppers, leafhoppers, plant bugs, leaf beetles, scarab beetles, the larvae of weevils, the larvae of midges and other small flies, grasshoppers, and other insects (see Insect Table). Some vertebrate animals use sunflowers as a food source. The seeds of these wildflowers are eaten by the Hungarian Partridge, Bobwhite, Mourning Dove, Eastern Goldfinch, Tufted Titmouse, Harris Sparrow, and many other birds. Small mammals that occasionally eat the seeds include the Gray Squirrel and other tree squirrels, Thirteen-Lined Ground Squirrel, Meadow Vole, White-Footed Mouse, and Plains Pocket Gopher. This gopher also feeds on the rhizomes of sunflowers in relatively dry sandy areas. The Cottontail Rabbit browses on the foliage of seedlings and lower leaves of mature plants, while the White-Tailed Deer occasionally chomps off the stems and upper leaves of mature plants. Because the Woodland Sunflower and other sunflowers are relatively tall and often form dense colonies, they provide good ground cover for many kinds of wildlife.
Photographic Location: A moist sand prairie at the Indiana Dunes National Lakeshore in NW Indiana. Comments: The Woodland Sunflower is easily identified by its sessile, or nearly sessile, opposite leaves. Other sunflowers (Helianthus spp.) have longer petioles. Its stems are usually hairless or mostly hairless, unlike Helianthus hirsutus (Hairy Sunflower) and some other species in this genus. Compared to some narrow-leaved sunflowers that occur in prairies, the leaf bases of Woodland Sunflower are more broad and nearly truncate. Some parasitic plants that occasionally attach their haustoria (root-like extensions) to sunflowers and other species in the Aster family include Cuscuta glomerata (Rope Dodder) and other Cuscuta spp. (generally in moist areas that are often sandy), and Orobanche ludoviciana (Prairie Broomrape) and other Orobanche spp. (generally in dry areas that are often sandy). These parasitic plants can significantly weaken the host plants to which they become attached.
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Miss Chen
2018年03月26日
Miss Chen
Description: This perennial wildflower is about 3-5' tall; it is erect and branches occasionally. The stems are light green, pale reddish green, or purple; the upper stems have short bristly hairs, while lower stems are glabrous and sometimes glaucous. The lower and middle leaves are opposite, while the upper leaves are alternate; they spread outward from the stems. The leaf blades are up to 7" long and 3" across; they are broadly lanceolate to ovate with long slender tips and sharply serrated margins. The upper surface of each leaf is dark green and rough in texture, while the lower surface is light green and nearly hairless. The petioles of the leaves are about ½–1½" long; they are somewhat winged near the leaf blade, but become more narrow toward the stem. The upper stems terminate in yellow flowerheads on naked stalks (peduncles) of varying length. Each flowerhead is about 2–3½" across, consisting of 8-12 ray florets that surround numerous disk florets in a central disk. The petal-like ray florets are bright yellow and oblong in shape, while the disk florets are yellow and tubular. The base of each flowerhead consists of several overlapping bracts. These floral bracts are light green, linear-lanceolate, and ciliate along their margins; they often curve backward. The blooming period occurs from mid-summer to early fall and lasts about 1–1½ months. Each fertile floret is replaced by a dark achene about 1/8" (3 mm.) in length (or a little longer) that is oblongoid and slightly flattened. The root system is fibrous and rhizomatous. Vegetative colonies of plants are often formed from the rhizomes. Cultivation: The preference is partial sun or dappled sunlight, moist to mesic conditions, and a rich loamy soil. Like other perennial sunflowers, this species may spread aggressively in some situations. Range & Habitat: The native Ten-Petal Sunflower is occasional in Illinois and widely scattered throughout the state; it is largely absent in south-central Illinois (see Distribution Map). Habitats include open woodlands, woodland borders, savannas, partially shaded areas along rivers, meadows, and thickets. Occasional disturbance is beneficial if it prevents excessive shade from overhead trees. Faunal Associations: The flowerheads attract many kinds of insects, especially bees (both long-tongued & short-tongued), which suck nectar and collect pollen from the florets. Other visitors include butterflies, wasps, and various kinds of flies. An impressive variety of insects feed on various parts of Helianthus spp. (Sunflowers), including beetles, weevils, and the caterpillars of some butterflies and moths (see Insect Table for some examples). The seeds are an attractive source of food to many upland gamebirds and granivorous songbirds (see Bird Table). Muskrats occasionally feed on the leaves and stems; they use the latter in the construction of their lodges in wetlands. Young plants are occasionally eaten by rabbits, deer, and groundhogs; they are also palatable to many kinds of livestock.
Photographic Location: A woodland opening at Meadowbrook Park in Urbana. The long slender bracts of a flowerbud can be seen in the upper leaf corner of the upper photograph. In the lower left of the same photograph, the long slender tip of a leaf blade is fully visible. Both photographs show the long pointed teeth along the margins of the leaf blades. Comments: This is an attractive woodland sunflower that should be cultivated in gardens more often. There are many species of sunflowers in Illinois (both prairie and woodland) and they are often difficult to identify. Ten-Petal Sunflower has the following characteristics that are useful in identifying this species: 1) the margins of its leaf blades have teeth that are long and pointed, 2) the tips of its leaf blades are unusually long and slender, and 3) the floral bracts are unusually long and slender. However, some populations of plants may have shorter teeth on the leaf margins.
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Miss Chen
2018年03月26日
Miss Chen
Description: This herbaceous perennial plant is 1½–2½' tall, branching occasionally. The round stems are light green and covered with coarse spreading hairs. Both basal and cauline leaves are produced; the cauline leaves are alternate, becoming smaller as they ascend the stems. The basal and lower cauline leaves are oddly pinnate (often with 5 leaflets), while the upperFlower, Stems, & Leaves cauline leaves are trifoliate or simple. The simple leaves and leaflets of the compound leaves are up to 3" long and 2½" across. They are lanceolate to ovate-oval, coarsely serrated or shallowly cleft along the margins, and largely hairless. Sometimes the leaves and leaflets are deeply cleft into 2 or 3 lobes. The terminal leaflet is larger in size than the lateral leaflets. The basal and lower cauline leaves have stout petioles, while the upper cauline leaves are nearly sessile. At the base of each petiole, there is a pair of leafy stipules that are cleft or dentate; each stipule is up to ½" long. The upper stems individually terminate in 1-3 flowers; sometimes single flowers are produced from the axils of the upper leaves. Each flower develops from a stalk (peduncle) up to 3" long; this stalk is covered with coarse spreading hairs. Each flower is about ½" across, consisting of 5 petals that are white or cream, 5 triangular green sepals, and several stamens surrounding a large cluster of green carpels with elongated styles. The petals are shorter than the sepals. The anthers are usually dull yellow or tan. The receptacle of the flower (underneath the carpels) is hairless or nearly so. The blooming period occurs from late spring to mid-summer and lasts about a month. There is no noticeable floral scent. Each flower is replaced by a spheroid cluster of achenes with elongated styles that are hooked at their tips. This fruiting cluster is about ¾" across; it is initially green, but eventually turns brown. The root system consists of a taproot and rhizomes; vegetative offsets are often formed. Cultivation: The preference is partial sun, moist to mesic conditions, and soil containing loam or sandy loam. Full sun and light shade are also tolerated. Range & Habitat: The native Rough Avens occurs occasionally in central and northern Illinois, but it is absent from the southern and southwestern areas of the state (see Distribution Map). Habitats include savannas, thickets, woodland borders, and moist meadows. Sometimes it is found in thickets and prairie remnants along railroads and roadsides. Faunal Associations: Information about floral-faunal relationships for this species is rather limited. They are probably similar to those of Geum canadense (White Avens). The nectar and pollen of the flowers probably attract small bees, wasps, and flies. Insects that feed on the foliage of Geum spp. (Avens) include the aphids Acyrthosiphon pseudodirhodum, Macrosiphum gei, Macrosiphum pallidum, and Macrosiphum pseudorosae. In addition, larvae of a moth, Tinagma obscurofasciella, mine the leaves. The achenes with hooked styles can cling to the fur of mammals, feathers of birds, and clothing of humans; by this means, they can be distributed across considerable distances.
Photographic Location: Between a thicket and prairie remnant along a railroad in Champaign County, Illinois. Comments: Rough Avens blooms a little later than Geum vernum (Spring Avens), but a little earlier than Geum canadense (White Avens) and Geum virginianum (Pale Avens). It can be confused with White Avens. However, Rough Avens has petals that are shorter than the sepals and its flowering stalks have coarse spreading hairs. White Avens has petals that are as long or longer than the sepals and its flowering stalks are finely pubescent. Pale Avens also has an appearance that is similar to Rough Avens; it is restricted to southern Illinois. Pale Avens has slightly smaller flowers (about 1/3" across) with cream petals that are much shorter than the sepals. The receptacles of its flowers are bristly-hairy, while the receptacles of Rough Avens are hairless or nearly so.
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Miss Chen
2018年03月26日
Miss Chen
Description: This herbaceous perennial plant is about 1½–2½' tall, branching occasionally. The upper stems are light green and pubescent, while the lower stems are often brownish green and coarsely hairy. These stems are round in circumference, rather than angular. There are both basal leaves (produced during the spring) and alternate cauline leaves. The basal leaves are produced in a low rosette up to 6" across. The lower cauline leaves are trifoliate, while the upper cauline leaves are usually simple; they are rather variable in shape. Both simple leaves and leaflets of the compound leaves are up to 4" long and 3" across, becoming smaller as they ascend the stems. They are medium green, lanceolate to oval-ovate, coarsely serrated, and often cleft into 3 major lobes. Their margins are often shallowly cleft or incised as well. The basal leaves are similar to the cauline leaves, except they are dark green and odd-pinnate with more than 3 leaflets. The wrinkled upper surface of each leaf is either hairless or it has scattered hairs that are very short and bristly; the lower surface is either hairless or it has a few hairs along the major veins. The lower leaves have stout petioles up to 1" long, while the upper leaves have either short petioles or they are sessile. At the base of each petiole, there are a pair of leafy stipules up to ½" long that are usually toothed along their margins. Each upper stem often terminates in an inflorescence of 1-3 flowers; sometimes individual flowers are produced from the axils of the upper leaves. The peduncles are up to 3" long and finely pubescent; they divide into shorter pedicels when there is more than one flower in the inflorescence.
Each flower is about ½" across, consisting of 5 bright white petals, 5 triangular green sepals, and numerous stamens surrounding a cluster of green carpels with elongated styles. The sepals are the same length or shorter than the petals; they are initially spreading, but curve downward with age. The anthers of the stamens are initially white, but they soon turn brown. The receptacle of each flower (the surface underneath the carpels) is pubescent. The blooming period occurs during the summer and lasts about 1-2 months. There is no noticeable floral scent. Each flower is replaced by a spheroid cluster of achenes with persistent styles that are hooked at their tips. This fruiting cluster spans about ¾" across; it is initially green, but eventually turns brown. The root system consists of a taproot and rhizomes; from the latter, vegetative offsets can be produced. This plant occasionally forms loose colonies.
Cultivation: The preference is light shade or partial sun, moist to slightly dry conditions, and a loam or clay-loam soil. At favorable sites, this plant can spread aggressively and is somewhat weedy. White Avens is able to grow underneath Black Walnut trees (Juglans nigra) because of its tolerance to the phytotoxic chemicals that are released by the fallen leaves and roots of this tree. Range & Habitat: The native White Avens is a common plant that occurs in every county of Illinois (see Distribution Map). Habitats include mesic deciduous woodlands, woodland borders, thickets, partially shaded seeps, fence rows with woody vegetation, powerline clearances in wooded areas, and edges of yards. Sometimes White Avens can be found in disturbed meadows and tall-grass prairies, but this is less typical. It adapts well to disturbed areas.
Faunal Associations: The flowers attract various insects, including bees, wasps, flies, and beetles. These insects suck nectar; some bees also collect pollen, while Syrphid flies often feed on the pollen. Insects that feed on the foliage of White Avens and other Aven species (Geum spp.) consist primarily of aphids, including Acyrthosiphon pseudodirhodum, Amphorophora rossi (White Avens is the preferred host plant), Macrosiphum gei, Macrosiphum pallidum, and Macrosiphon pseudorosae. In addition, the larvae of a moth, Tinagma obscurofasciella, mine the leaves. Apparently the foliage of White Avens is not attractive to mammalian herbivores; it is not often grazed by White-Tailed Deer. The hooked achenes can cling to the fur of mammals, feathers of birds, and clothing of humans; by this means, they are distributed far and wide. Photographic Location: The photographs were taken near a powerline clearance at Busey Woods in Urbana, Illinois, at a tallgrass prairie of Meadowbrook Park in the same city, and along a woodland border at Chief Shemauger Park in the same city.
Comments: The flowers of White Avens resemble those of various Rubus spp. (Blackberries), except that they are a little smaller. The structure of its flowers is typical of many species in the Rose family. This is probably the most common Geum sp. (Avens) in Illinois. In general, White Avens can be distinguished from other species of Avens by its bright white petals, which are as long or longer than the sepals. Its lower cauline leaves are trifoliate, whereas the lower cauline leaves of other species of Avens are often oddly pinnate with 5 or more leaflets. In particular, Geum laciniatum (Rough Avens) resembles White Avens and occurs in many of the same habitats. However, the petals of its flowers are shorter than the sepals. The flowering stalks of White Avens are finely pubescent, while the flowering stalks of Rough Avens have coarse spreading hairs. Another species, Avens virginianum (Pale Avens), is restricted to southern Illinois. The petals of its flowers are cream rather than bright white, and they are substantially shorter than the sepals. Unlike White Avens, its lower cauline leaves are often odd-pinnate with 5 leaflets.
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Miss Chen
2018年03月25日
Miss Chen
Gardeners have long known that some plants seem to grow better when grouped together, while others seem to conflict. Companion planting is a gardening technique that emphasizes plant compatibility; for instance, climbing vines and tall plants, such as tomatoes and corn, work well when paired with low-growing crops, such as beets and cucumbers, since they do not compete with each other for space.
Companion Planting Choosing plants that are able to share space harmoniously allows gardeners to place different specimens close together, maximizing the productivity of a given area. The secret to successful companion planting is choosing vegetables that balance each other and have similar environmental needs. Vegetables that compete for nutrients, sunlight, or root space make poor companions. For example, tall, heat-loving, long-season plants are complemented by short-season, ground-hugging plants or small, below-ground crops. Tomatoes Tomatoes are a vegetable garden favorite, but they are also heat lovers that require full sun. As such, they cannot be planted beneath other garden plants. However, the area around the base of a tomato plant is often an ideal location for shallow-rooted, shade-tolerant plants, or bite-sized root vegetables. Surround tomatoes with beets, baby carrots, garlic, green onions, sage, chives and marigolds for the best results; not only to these plants grow well in the shade provided by towering tomato plants, they seem to improve the productivity of the tomato vines. Beets Beets are valued for both their flavorsome roots and their leafy tops. They are well adapted to most climates and flourish when set in full sun or partial shade; however, they tend to grow best in temperate regions and flourish when planted near bok choy, broccoli, cauliflower, bush beans, cabbage or tomatoes. This mid-season plant can be set out three weeks before the expected date of the final frost. Once the young sprouts emerge, they are ready to harvest 48 to 50 days later. This opens up a small area of the garden that can then be replanted with a short-season vegetable such as radishes or lettuce.
Spacing Companion plants can be set fairly close together, saving valuable garden space. To determine the appropriate distance between companion plants, combine the suggested spacing for each plant, then divide the total by two. For example, beets should be spaced 4 inches apart, and tomatoes should have at least 24 inches of room between them. Allow at least 16 inches between beets and tomatoes.
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Miss Chen
2018年03月25日
Miss Chen
Cucumbers, squashes and melons are all in the cucurbita family of plants. Most of them make long vines, but some do not. They look very similar as seedlings, but as they begin to flower and make fruit, it is easier to tell them apart in the garden. Looking at the flower size, the shape of the tiny fruit behind the female flowers, and the general habit of the plant will give you an idea of what vegetable you are looking at.
Step 1 Observe the growth habit of the plant in question. Cucumber and melon plants are usually smaller at first than squash plants. The leaves are smaller, and the stems are not as thick. Summer and winter squash plants grow very fast in the early days of summer, whereas melon and cucumber plants take a while to get big. Step 2 Look at the shape of the leaf. A watermelon plant has a characteristic appearance: it is more deeply lobed than a cantaloupe, squash or cucumber leaf. If you are looking at a watermelon plant, it is likely that the vines have started running along the ground almost immediately.
Step 3 Determine if the plant is trying to climb upwards using tendrils, or if it is running along the ground. A cucumber plant will attempt to grow vertically, putting out strong tendrils that will grab onto anything and pull the plant upwards. Some melons will climb, although more weakly. Summer squash never puts out tendrils, although some winter squash do. Summer squash will stay bushy rather than sending out vines and tendrils along the ground. Step 4 Check the stem to see if it is somewhat spiny. The stems of squash plants are often somewhat prickly, whereas cucumbers and melons never are. Their stems are somewhat fragile looking compared to squash stems. Next, observe the flower, once the plant begins flowering. Cucumber and melon flowers will be small, about the size of a nickel, whereas squash flowers are large, several inches across. The flowers open in the morning, and there are male and female flowers. The female flowers will be the ones that form the fruit. Step 5 Check below the flower and see if a small fruit is forming there. Once the female flower has been pollinated by insects, the flower will close and wilt, and a small fruit will form at the base of the flower. Look at the size and shape of this fruit to see what kind of cucurbita it is. Cucumbers will usually form long thin fruits, a watermelon or cantaloupe will be round, and some winter squash have a characteristic bulge at one end of the fruit.
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Miss Chen
2018年03月25日
Miss Chen
The Persian cucumber (Cucumis sativus "Persian") is a variety of burpless cucumber, meaning its consumption is less likely to cause gastrointestinal upset than other types. This cucumber is also small, sweet and essentially seedless. It's also known as Beit Alpha cucumber, a name that indicates the community in northern Israel where the fruit was originally developed. Appearance and Flavor
In contrast to the thick, bumpy skin of the common garden cucumber (Cucumis sativus), the Persian cucumber features a smooth, thin skin that doesn't require peeling. Its flesh is largely free of bitter-tasting seeds and is firm instead of watery, attributes that lend crunch and a mild sweetness. Growth Habit
Like other members of the gourd family, the Persian cucumber grows as a creeping vine that appreciates a trellis or other vertical support to increase spread as well as reduce the risk of powdery mildew and other soil-borne diseases. As a tropical species, the plant requires a minimum soil temperature of 70 degrees Fahrenheit and at least six hours of full sun each day. Because this annual cannot withstand frost or cold temperatures, the Persian cucumber is one of the last annual crops to be planted in the garden in spring and is best suited for U.S. Department of Agriculture plant hardiness zones 4 through 12. Harvesting and Use
The ideal time to pick a Persian cucumber is when the fruit reaches 4 to 6-inches in length. If it's allowed to grow bigger, bitter seeds may develop that will compromise the flavor. Harvesting mature fruit encourages the production of more cucumbers. When harvesting, cut, rather than pull, the fruit from the stem. Persian cucumbers are commonly used as a slicing cucumber for salads and appetizers, although their crisp texture also makes them suitable for pickling. Because they blend well with a variety of spices, herbs and vegetables, they work well in dressings, dips and salsas. Notable pairings include cumin, mint, parsley, black pepper, garlic, onion and tomato. Available Cultivars
There are several cultivars of Persian cucumber, each with different qualities. Diva ("Cucumis sativus "Diva") often produces a heavier cucumber but less fruit overall. The cultivars that tend to produce the highest yield include Rambo ("Cucumis sativus "Rambo") and Sarig ("Cucumis sativus "Sarig"). Snack-sized cultivars like Silor ("Cucumis sativus "Silor"), which are typically one-third smaller, are good "take-alongs" because they fit easily into a small container or lunchbox.
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