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Miss Chen
2018年07月11日
Miss Chen
Description: This herbaceous perennial plant forms both basal leaves and erect to ascending stems with alternate leaves; the latter are 2-4' tall, branching occasionally. The stems are grayish green to nearly white, densely canescent, and terete, becoming more glabrous and slightly woody with age. Both the basal and lower alternate leaves are 2–4½" long and ¾–1¾" across (excluding their petioles); they are bipinnatifid to tripinnatifid. These leaves are deeply divided into primary lobes, while their ultimate lobes are more shallow and cleft. The ultimate lobes are 2-4 mm. across and narrowly oblong to narrowly oblanceolate in shape, tapering abruptly into bluntly acute tips. The middle alternate leaves are less divided and slightly smaller in size, while the upper alternate leaves are simple or sparingly lobed and even smaller in size. Both the upper and lower sides of the leaves are grayish green and sparsely to moderately canescent. The basal and lower alternate leaves have long petioles, while the middle alternate leaves have shorter petioles, and the upper alternate leaves are sessile or nearly so. Like the leaves, the petioles are grayish green and canescent. The foliage of this plant has a sage-like aroma with slightly bitter overtones. The upper stems terminate in panicles of flowers. Along the primary rachises of these panicles, there are primary leafy bracts at the bases of the secondary rachises; these primary bracts are up to 1" long, linear-oblong in shape, grayish green to nearly white, and canescent. Secondary leafy bracts also occur at the bases of the peduncles on the secondary rachises; these secondary bracts are similar to the primary leafy bracts, except they are smaller in size. Both the primary and secondary rachises of the panicles are grayish green to nearly white and moderately to densely canescent; they are flat or slightly concave along their upper sides and rounded along their lower sides. The nodding flowerheads are 3-5 mm. across and 2-3 mm. tall; they are subgloboid in shape. Each flowerhead has 20-40 perfect disk florets that are surrounded by 10-20 pistillate disk florets; both types of florets are fertile. The florets are seperated by abundant silky hairs that originate from the receptacle. The tiny corollas of these florets are tubular in shape and 5-lobed along their upper rims. Overall, the appearance of these florets is yellowish brown. Along the sides of each flowerhead, there are small appressed phyllaries (floral bracts) in several overlapping series; these floral bracts are whitish green, densely canescent, and oblong to ovate in shape. The flowerheads have short curved peduncles that are whitish green and densely canescent. The blooming period occurs from mid-summer to early autumn, lasting 2-3 weeks for a colony of plants. The florets are cross-pollinated by the wind. Afterwards, the florets are replaced by small achenes. Mature achenes are 0.5–1 mm. long, narrowly oblongoid-oblanceoloid in shape, and light brown; they lack tufts of hair. The root system consists of a taproot up to ½" across. This plant reproduces by reseeding itself.
Cultivation: The preference is full or partial sun, moist to dry-mesic conditions, and soil containing loam, clay-loam, or some gravel. The soil should be well-drained. The size of individual plants can be highly variable depending on their age, moisture conditions, and soil fertility. For a herbaceous wormwood species (Artemisia), Absinthe tends to be long-lived. Range & Habitat: Naturalized populations of Absinthe can be found in NE Illinois and scattered counties elsewhere, where it is relatively rare (see Distribution Map). All of these naturalized plants have escaped from cultivation. Absinthe was introduced into North America from Europe as an ornamental and medicinal plant. It is still cultivated occasionally in herb gardens today. In North America, this plant is more common in the northern plains of the United States and south-central Canada, where it is regarded as a weed of pastures. Habitats include pastures, sunny fence rows, gravelly areas along railroads, old homestead sites, and waste areas. Habitats with a history of disturbance are strongly preferred. In Illinois, Absinthe has difficulty to competing with taller native plants in natural areas.
Faunal Associations: Several species of aphids are known to feed on Absinthe (Artemisia absinthium); many of these species originated from Europe. Examples include such species as Coloradoa absinthii, Coloradoa angelicae, Coloradoa artemisiae, Macrosiphoniella absinthii (Absinthe Aphid), and other Macrosiphoniella spp. (Blackman & Eastop, 2013; Robinson & Bradley, 1965). Other insects that feed on wormwood species (Artemisia spp.) include Aphis middletonii(Erigeron Root Aphid), larvae of the leaf-miner fly Calycomyza artemisiae (Wormseed Webworm), larvae of the Gelechiid moth, Scrobipalpula artemisiella (Wormseed Webworm), and larvae of the Tortricid moths Eucosma agricolana and Phaneta dorsiatomana (Hottes & Frison, 1931; Spencer & Steyskal, 1986; Marcovitch, 1916; Miller, 1987). Some grasshoppers feed on these plants as well, including Hesperotettix viridis (Meadow Purple-striped Grasshopper), Hypochloa alba (Cudweed Grasshopper), and Melanoplus angustipennis (Narrow-winged Sand Grasshopper); see Vickery & Kevan (1985). Because the foliage of Absinthe is aromatic and bitter, it is not preferred as a source of food by herbivorous mammals. However, cattle and other domesticated livestock will feed on the foliage of Absinthe if little else is available. The consumption of a large quantity of foliage is potentially harmful as it contains the neurotoxin, thujone.
Photographic Location: An herb garden at Meadowbrook Park in Urbana, Illinois. Comments: Absinthe (Artemisia absinthium) has been used to flavor an alcoholic liquor by the same name. Excessive consumption of this liquor has the potential to cause toxic effects and its use in some countries has been banned. Absinthe is similar in appearance to several other wormseed species (Artemisia spp.); both native and non-native species are present in Illinois. A native species that occurs in sandy areas, Beach Wormwood (Artemisia campestris), can be distinguished by the longer length and narrowness of the lobes of its leaves, the sterile florets in the center of its flowerheads, and the lack of villous hairs on the receptacle of its flowerheads. The presence of the last characteristic (villous hairs on the receptacles of the flowerheads) distinguishes Absinthe from all other wormseed species in Illinois, except for Prairie Sagebrush (Artemisia frigida). Prairie Sagebrush has smaller leaves with more narrow lobes (1 mm. across or less) than Absinthe, while its flowerheads are slightly larger in size (5-6 mm. across and 3-5 mm. tall). It is primarily a western species that is rarely found in Illinois.
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Miss Chen
2018年07月11日
Miss Chen
Description: This perennial wildflower develops a rosette of basal leaves, from which there develops one or more flowering stalks about 1¾-4' tall. The blades of the basal leaves are ½-2' long and 1½-6" across; they are broadly oblong-elliptic in shape and finely crenate-serrate along their margins. The petioles of the basal leaves are often as long as the blades. The basal leaves are widely spreading and rather floppy; their margins often undulate up-and-down. The stems of Horseradish are light to medium green and glabrous. Alternate leaves become smaller in size as they ascend these stems; their blades are 1-6" long and ¼-2" across. The blades of alternate leaves are narrowly elliptic to broadly oblong-lanceolate in shape and their margins are coarsely crenate-serrate to shallowly pinnatifid; they are sessile or with short petioles. The upper blade surfaces of both basal and alternate leaves are medium to dark green and glabrous, while their lower surfaces are a more pale shade of green and glabrous below. The central stem and upper axillary stems terminate in either racemes or panicles of flowers about 4-16" in length. The flowers bloom toward the apex of each raceme (or branch of a panicle), while seedpods develop below. Each flower spans about 1/3" (8 mm.) across, consisting of 4 white petals, 4 light green sepals, 6 stamens, and a pistil with a short style. The petals are about twice the length of the sepals. The ascending pedicels are ¼-¾" in length, light green, and glabrous, becoming longer as the seedpods develop. The central stalks and branches of the racemes and panicles are light green and glabrous. The blooming period can occur from mid-spring to mid-summer and lasts about 2 months. The flowers are replaced by cylindrical seedpods up to ¼" (6 mm.) long; each seedpod can contain up to 8 seeds. The root system consists of a stout taproot and stout rhizomes. Clonal colonies of plants are often produced.
Cultivation: The preference is full or partial sun, moist conditions, and fertile soil containing loam or silt-loam. Because of its underground rhizomes, Horseradish can spread aggressively. Range & Habitat: The non-native Horseradish is occasional in most areas of Illinois, except in the SE section of the state, where it is rare or absent (see Distribution Map). This plant was introduced into North America from Europe during colonial times; it is native to SE Europe and parts of SW Asia. Habitats include streambanks, ditches, fence rows, low areas along roads and railroads, abandoned fields, vacant lots, disturbed open woodlands, and waste areas. Horseradish is still cultivated in gardens as a culinary herb. It is usually found in disturbed areas.
Faunal Associations: The nectar and pollen of the flowers attract small bees, flies, small butterflies, and probably other insects. Several leaf beetles (Chrysomelidae) have been observed to feed on Horseradish, specifically: Entomoscelis americana, Phaedon laevigatus, Phyllotreta armoraciae (Horseradish Flea Beetle), Phyllotreta bipustulata, Phyllotreta conjuncta, Phyllotreta cruciferae, Phyllotreta oblonga, Phyllotreta punctulata, Phyllotreta striolata, and Phyllotreta zimmermanni (see Clark et al., 2004). These species are mostly flea beetles (a subfamily of leaf beetles) that feed on the foliage and sometimes the roots. Other insect feeders include Murgantia histrionica (Harlequin Bug), the caterpillars of Lascoria ambigualis (Ambiguous Moth), and the caterpillars of Pieris rapae (Cabbage White). Because of high levels of mustard oil from the conversion of glucosinolates, Horseradish can produce toxic effects on mammalian herbivores, especially the pungent roots. Photographic Location: A roadside ditch in NW Ohio, and the Toledo Botanical Garden in Toledo, Ohio.
Comments: In the United States, the thick roots of Horseradish are grated to flavor various sauces for food (primarily dishes of beef, pork, and seafood). Such sauces usually contain vinegar, mayonnaise, or pureed tomatoes. Because of the warm climate during summer and the long growing-season, Horseradish usually produces both seedpods and viable seeds in Illinois and other areas of the lower Midwest. Apparently this rarely happens in Great Britain and other areas of Europe where the climate is cool and the growing-season is too short. However, Horseradish is readily propagated by dividing its roots. Because of the size and abundance of its flowers, Horseradish is fairly showy while it is in bloom, especially for a species in the Mustard family. It is also larger in size than most species in this plant family. Horseradish can be distinguished from similar species by the size of its white flowers (about 1/3" or 8 mm. across), the appearance of its basal and alternate leaves, its small cylindrical seedpods, and the pungent odor of its roots. Because the classification of Horseradish has been unstable in the past, it is sometimes referred to as Armoracia lapathifolia, Cochlearia armoracia, and Rorippa armoracia.
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Miss Chen
2018年07月11日
Miss Chen
Haworthia are delightful little succulents that form very attractive and singular small houseplants. Generally easy to grow, the same best practices that yield healthy aloe and echeveria plants will also produce beautiful Haworthia.
In terms of appeal, these small, low growing plants form rosettes of fleshy green leaves that are generously covered with white, pearly warts or bands, giving them a distinctive appearance. Just like other succulents, these plants appreciate bright light, adequate moisture in the summer, and relatively drier conditions in the winter. Avoid overwatering, but don’t let them dry out too much. Growing Conditions Light: Bright light, but not direct sunlight. These grow in similar conditions to other succulents. White or yellow leaves usually signify too much sun. Water: Water evenly and generously in the summer, letting the soil media dry out between waterings. In the winter, reduce watering to every other month. Never allow water to collect in the rosette. Temperature: Warmer summers but cool in the winter (down to 50 degrees F). Soil: Use a cactus mix or very fast-draining potting soil mixed with sand. Fertilizer:Fertilize during the summer growing season with a cactus fertilizer. Don't feed during the winter. Propagation Haworthia can be propagated at repotting time using offsets from the mother plant. When taking offsets, use a sharp knife or snippers and cut as close to the mother stem as possible to include as many roots as possible, then allow the offset to dry briefly before repotting it (similar to cuttings from other succulents). Pot the offsets in a small pot, using the same soil as the mother plant, put it in a warm, bright spot, and make sure to adequately water. Repotting Haworthia are small (usually remaining between 3" and 5" in height) and relatively slow-growing. They are often grown in small clusters in wide, shallow dishes. Over time, clusters will naturally enlarge as the mother plant sends off small plantlets. When the cluster has outgrown its dish, repot in the spring or early summer into a new wide and shallow dish with fresh potting soil. This is also the time to take offsets for propagation.
Varieties There are about 80 species of Haworthia, but their classification can be complex. The main difference between the common species is the size of the leaves and the orientation of the white markings on the leaves. H. margaritifera has warty white projections on the leaves, while H. fasciata features horizontal white stripes and is sometimes called the zebra plant. Some of the species, such as H. bolusii have "tufted" edges to the leaves, while H. attenuata features long, pointed green leaves. In general, the best advice is to buy the most attractive variety based on leaf form and markings, as they all have similar cultural requirements. Grower's Tips Haworthia are not considered difficult houseplants to grow—if you can keep a pot of aloe alive on a windowsill, chances are you can do the same with a dish of Haworthia. As with all succulents, the most dangerous situation is too much water, since they should never be allowed to sit in water under any circumstances. At the same time, these little decorative plants can be grown in interesting containers such as teacups and even miniature baby shoes. If you're given a Haworthia in such a container, make sure the container had adequate drainage. If it doesn't, it might be a good idea to pop the plant out of its container and add a layer of gravel to the bottom to reduce the wicking action of the soil above. Finally, look out for sunburned spots on your plants.
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Miss Chen
2018年07月11日
Miss Chen
Peppers are a popular plant for the home vegetable garden. The three most common varieties of peppers are bell peppers, hot peppers and sweet peppers. Although peppers are relatively easy to grow, several factors can result in low fruit production. If you want to get your green pepper plants to produce more, be vigilant with their care.
Step 1 Monitor temperatures. Peppers prefer warm whether, so avoid planting them until after the last frost of the season and cover them if frost is expected. Some varieties suffer during extended periods of extreme heat as well and require shading. Optimal temperatures for growing peppers range from roughly 70 to 85 degrees Fahrenheit. Step 2 Provide proper nutrients. Fertilizer rich in nitrogen will result in a leafy, healthy plant but won't yield much fruit. Use a phosphorus and potassium-rich fertilizer as the plants begin to develop. Step 3 Remove the first few flower buds. This allows the plant to develop more before it begins producing fruit and sometimes results in higher fruit production. Step 4 Pick often. Picking fruits as they ripen encourages the plant to begin producing more fruit.
Step 5 Prune the plants. Moderate pruning in the late summer or early fall sometimes extends fruit production, but prune with care. Severe pruning damages the plant.
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Miss Chen
2018年07月10日
Miss Chen
Description: This herbaceous biennial plant is a low-growing rosette of basal leaves during the first year, but during the second year it becomes 3-6' tall. The second-year plant is little branched below, but produces short flowering side stems above. The stems are rather stout, round or slightly ridged in circumference, and light green to slightly reddish green. Young stems are covered with white cobwebby hairs, but older stems become glabrous and have conspicuous longitudinal veins. The basal leaves are up to 2' long and 1½' across. They have long petioles and resemble the leaves of rhubarb to some extent. The lower leaves of second year plants resemble the basal leaves, except that they are somewhat smaller. These leaves are ovate-cordate, dull green above, and whitish green below, with blunt tips. They are nearly glabrous above, but finely pubescent below. Their margins are somewhat undulate, crisped, or smooth, sometimes with a few blunt teeth. Their long petioles have a conspicuous furrow above and they are usually hollow inside. The middle to upper leaves of second year plants are similar in appearance, but they are smaller in size and more likely to be ovate with margins that are more smooth and petioles that are shorter. The upper stems terminate in small clusters of flowerheads on short stalks. Each flowerhead is about ¾–1" across, consisting of numerous disk florets and floral bracts that have narrow hooked tips. There are no ray florets. Each disk floret has a corolla that is narrowly cylindrical with 5 slender upright lobes at the apex. The disk florets are usually some shade of pink or purple, although a rare form of Common Burdock with white florets occurs. The slender white style is strongly exerted from the corolla and bifurcated at its tip. The dark purple anthers form a sheath around the style that lies just above the lobes of the corolla. The abundant bracts are green at the base, but become yellowish green toward the their hooked tips. They have a spiny appearance and have few, if any, cobwebby hairs in their midst. The blooming period occurs from mid-summer to early fall, and lasts about a month for a colony of plants. The achenes are oblong, broader and more truncate at one end than the other, and light brown with dark brown speckles. At the apex, each achene has a crown of fine bristles, but these are deciduous and soon fall off. The floral bracts turn brown and enclose the withered flowers at the top, forming a bur. The burs are persistent and remain on the stalks after the leaves have withered away during the fall. The root system consists of a stout taproot that runs deep into the ground. This plant spreads by reseeding itself, and often forms colonies of variable size. Cultivation: Common Burdock is often found in full or partial sun, slightly moist to mesic conditions, and a loamy fertile soil. It has a robust nature and can be found in other kinds of soil and drier conditions. It is often aggressive.
Range & Habitat: This non-native plant is common in central and northern Illinois, but less common or absent in southern Illinois (see Distribution Map). This is by far the most common Arctium sp. (Burdock) in the state. It is adventive from Northern Europe and also occurs in Asia. Habitats include woodland edges, savannas, thickets, pastures, edges of fields and fence rows, weedy meadows, barnyards, areas along roads and railroads, and waste areas. Disturbed areas are preferred, although it occasionally appears in more pristine natural areas, particularly along paths and animal trails. Faunal Associations: The flowers are pollinated primarily by long-tongued bees, including bumblebees, honeybees, Miner bees, and Leaf-Cutting bees, which suck nectar and collect pollen. Other visitors include bee flies, butterflies, and skippers, which seek nectar and are also effective at pollination. The caterpillars of several Papaipema spp. (Borer Moths) bore through the pith of the stems, including Papaipema cataphracta (Burdock Borer Moth), Papaipema arctivorens (Northern Burdock Borer Moth), and Papaipema rigida (Rigid Sunflower Borer Moth). The foliage of Common Burdock is one of the food sources for the caterpillars of the butterfly Vanessa cardui (Painted Lady). The Ring-Necked Pheasant eats the seeds to a limited extent. Because the foliage is bitter-tasting, Common Burdock is not a preferred food plant for mammalian herbivores, although livestock and deer will browse on it if nothing else is available. There is some evidence that the foliage may be toxic to rabbits. The seeds are distributed far and wide by animals and humans because the burs cling readily to fur and clothing. They are quite difficult to remove.
Photographic Location: Along a fence row at the webmaster's apartment complex in Urbana, Illinois. Comments: Apparently, the stout taproot has a sweet taste and can be used as food. Similarly, if the outer husk of the stems are peeled away, the pith can be used like a vegetable. There are 3 Arctium spp. (Burdocks) in Illinois. One of them, Arctium tomentosum (Woolly Burdock) has abundant cobwebby hairs that cover the floral bracts below their hooked tips. Another species, Arctium lappa (Great Burdock), is often taller than Common Burdock, and it has larger flowerheads about 1–1½" across. The flowerheads of Great Burdock have longer stalks and they are arranged in flat-headed cymes, whereas the flowerheads of Common Burdock are more vertically bunched together on short stalks, as revealed in the upper photograph. The petioles of the lower leaves in Great Burdock are less furrowed on the upper surface and they are solid inside, rather than hollow.
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Miss Chen
2018年07月10日
Miss Chen
Description: This herbaceous plant is a winter or spring annual, producing leafy and flowering stems about 4-18" (10-45 cm.) long. These stems branch primarily near the base of the plant and they are ascending to widely sprawling. Individual stems are whitish green to light reddish green, terete, and woolly-pubescent. Alternate leaves occur along these stems that are ¾-2" (2-5 cm.) long and about one-half as much across; they are broadly oblong in outline, while their structure is deeply bipinnatifid. The ultimate leaf segments are 1.5-5.0 mm. long and about one-third as much across; these segments are oblong-acute in shape. The leaves are pale green and they are covered with short woolly pubescence that becomes more sparse with age. The short petioles are relatively broad, flattened, and whitish green to nearly white; they usually have simple or pinnate lobes along their margins that resemble the leaf segments. The upper stems terminate in individual flowerheads that span about ¾-1¼" (2-3 cm.) across; these flowerheads have peduncles that are 1½-6" (4-15 cm.) in length. These peduncles are pale green, terete, and woolly-pubescent. Usually, small alternate bracts occur along the peduncles that resemble the leaves. Each daisy-like flowerhead has 10-18 ray florets that surround numerous disk florets; the ray florets are fertile and pistillate, while the disk florets are fertile and perfect. The petaloid rays of the ray florets are white, oblong in shape, and notched at their tips. The tiny corollas of the disk florets are yellow, tubular in shape, and 5-lobed at their apices; these lobes are triangular in shape. Alongside the disk florets, there are chaffy scales about 4 mm. in length. These scales are oblanceolate in shape and their tips are acute; sometimes these tips are awn-like. At the base of each flowerhead, there are 1-2 series of phyllaries (floral bracts) that are broadly oblong in shape. Individual phyllaries have convex central ridges that are light green, wide membranous margins that are white to light brown, and woolly pubescence; the phyllaries become chaffy with age. The foliage of this plant lacks a significant fragrance, although the crushed flowerheads are mildly fragrant (resembling apple-pineapple). The flowerheads are solid, lacking hollow centers. The blooming period usually occurs from late spring to mid-summer, lasting about 1-2 months, although some plants may bloom later in the year.
At maturity, the seedheads are ovoid in shape. The achenes are 1.5-2.5 mm. in length, oblanceoloid in shape, and slightly 4-angled; they are truncate at their apices, where they lack tufts of hair or significant scales. The sides of mature achenes have longitudinal ribs that are readily visible. The achenes are distributed to a limited extent by wind and probably by water at some locations. The root system consists of a shallow much-branched taproot or it is fibrous. Reproduction is by seeds. Cultivation: The preference is full sun, moist to dry-mesic conditions, and a calcareous soil containing clay-loam, loam, silt, gravel, or sand. Drought tolerance is good. The seeds can remain viable in the ground for 10 years or more (Kay, 1971). Range & Habitat: Field Chamomile has been found in scattered locations across Illinois (see Distribution Map), but this non-native plant is relatively uncommon within the state. It was introduced into North America from Eurasia, where it is native. In Illinois, habitats consist of fallow fields, roadsides, flood zones along drainage canals and retention ponds, vacant lots and abandoned homestead sites, and waste areas. Highly disturbed areas are preferred.
Faunal Associations: The flowerheads probably attract small bees, various flies (including Syrphid flies), and other insects. Both nectar and pollen are available as floral rewards to such visitors. Insects that feed destructively on Field Chamomile and other Anthemis spp. include Polymerus basalis (Red-Spotted Aster Mirid) and two aphids, Macrosiphoniella tanacetaria and Macrosiphoniella tapuskae. The former aphid is typically found on the flowerheads, peduncles, and upper stems, while the latter aphid is typically found on the lower leaves. The polyphagous caterpillars of a moth, Orthonama obstipata (The Gem), have been reported to feed on mayweeds by Covell (1984/2005). Field Chamomile belongs to the group of plants that are commonly referred to as mayweeds in Europe. The foliage of Field Chamomile is probably browsed sparingly by mammalian herbivores, while Canada Geese seem to avoid it. Because the seeds can pass through the gastrointestinal tracts of both cattle and pigeons and remain viable (Kay, 1971), these animals may spread them to new areas. It is also possible for the seeds to cling to the bottoms of the muddy shoes of people and the muddy hoofs of animals, by which means they can spread to new areas. Photographic Location: Along a drainage canal and retention pond area in Champaign, Illinois.
Comments: Field Chamomile (Anthemis arvensis) is one of the plants that are commonly referred to as mayweeds. Examples of these species include Anthemis cotula (Dog Fennel), Chamaemelum nobile (Roman Chamomile), Matricaria recutita (German Chamomile), and Tripleurospermum perforatum (Scentless Chamomile). As a group, they are difficult to distinguish from each other. All of these species have daisy-like flowerheads that resemble those of Leucanthemum vulgare (Ox-Eye Daisy), but their foliage is deeply dissected (typically bipinnatifid). Field Chamomile can be distinguished from other mayweeds by its flat leaf-segments (rather than terete leaf-segments), by the presence and shape of the chaffy scales in its flowerheads, by the woolly pubescence of its foliage, and by the appearance of its achenes. The foliage of Field Chamomile lacks the pleasant fragrance of Roman Chamomile, nor does it possess the unpleasant odor of Dog Fennel. Similar to German Chamomile, the crushed flowerheads of Field Chamomile are mildly fragrant, but it has completely solid flowerheads, whereas the flowerheads of German Chamomile have interiors that are partly hollow.
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Miss Chen
2018年07月10日
Miss Chen
Description: This herbaceous plant is a winter or spring annual that forms a low rosette of several basal leaves up to 4 cm. (1½") across. Individual basal leaves are 0.5–2 cm. (¼–¾") long and about one-third to one-half as much across; they are elliptic to broadly elliptic in shape, bluntly dentate toward their tips, and sessile. The leaf surface is medium green to reddish green (rarely red); its upper surface has sparse minute pubescence, while its lower surface is glabrous. Each rosette of basal leaves develops 1–15 flowering stalks that are 2.5 cm. (1") to 7.5 cm. (3") tall. These stalks are light green, reddish green, or red; they are short-pubescent, terete, and either erect or arching upward. The flowering stalks terminate in either solitary flowers or umbels of flowers (usually the latter); there are 2–10 flowers per umbel. Sometimes 1–2 secondary stalks will originate from an umbel of flowers to produce secondary umbels of flowers, making an inflorescence a partially compound umbel of flowers. The secondary flowering stalks are similar to the primary flowering stalks, except they are usually shorter. The secondary umbels of flowers are similar to the primary umbels of flowers, except they tend to have fewer flowers. The pedicels of the flowers (or seed capsules) are 3–25 mm. (1/8–1") in length and erect to upwardly arching. Compared to the flowering stalks (peduncles), the pedicels are shorter and more slender, although they become longer as the seed capsules develop. Individual flowers are about 2 mm. across and 4 mm. long; each flower has a green calyx with 5 erect teeth, a white tubular corolla with 5 ascending lobes, 5 inserted stamens with short filaments, and a light green ovary with a single short style. The calyx is 5-angular from 5 ridges and it has sparse minute pubescence. The teeth of the calyx extend above the lobes of the corolla. Individual lobes of the corolla are lanceolate in shape. The teeth of the calyx are narrowly deltate to deltate in shape and a little shorter than the angular calyx-tube.
At the base of each umbel (or secondary umbel) of flowers, there are 2 or more leafy bracts that resemble the basal leaves, except they are smaller in size (less than 0.5 cm. or ¼" in length) and they lack teeth; sometimes they form a small rosette. The blooming period occurs from from early to late spring, lasting about 1 month. The flowers are inconspicuous. Afterwards, they are replaced by small seed capsules. These capsules are about 3 mm. long and ovoid in shape; each capsule eventually divides into 5 sections to release several seeds. These seeds are small enough to be blown about by the wind. Mature seeds are about 1 mm. long, 0.75 mm. across, 3-angled, and dark brown to black; the seed surface has a network of minute ridges and pits. The root system consists of a slender taproot. This plant reproduces by reseeding itself. It dies down no later than mid-summer. Cultivation: The preference is full to partial sun, mesic to dry conditions, and a barren soil containing sand, gravel, clay, or rocky debris. Most growth and development occurs during the spring, which happens very quickly.
Range & Habitat: Western Rock Jasmine (Androsace occidentalis) is a native plant in Illinois, where it occurs occasionally in western and northern Illinois, while in the rest of the state it is uncommon or absent (see Distribution Map). This plant is more common in drier areas to the west of Illinois. In Indiana, Ohio, and Michigan, this plant is rare and state-listed as 'threatened' or 'endangered.' Habitats include gravel hill prairies, upland sand prairies, upland dolomite prairies, gravelly or sandy areas along railroads, roadsides, pastures, fallow fields, and waste ground. In Illinois, Western Rock Jasmine occurs in both higher quality natural areas and disturbed areas on exposed ground soil where it is dry and sunny. Faunal Associations: This plant becomes more common in pastures that are moderately to heavily grazed by cattle as this reduces competition from taller and more aggressive plants (Patton & Nyren, 2015).
Photographic Location: Found on waste ground along an alley way in Urbana, Illinois. This dumped waste ground contained broken bricks and pieces of concrete. Comments: This tiny plant has inconspicuous flowers and it is easily overlooked. When the stalks with umbels of flowers are produced, it fairly easy to identify, however. Western Rock Jasmine (Androsace occidentalis) is the only species of its genus that has been found in Illinois. Further to the west, however, there are several Rock Jasmine species (Androsace spp.). These more western species tend to be less weedy in appearance and they have showier flowers. Other common names for Androsace occidentalis are Western Rock Primrose and Western Fairy Candelabra. Sometimes this plant is simply referred to as Rock Jasmine, Rock Primrose, or Fairy Candelabra.
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Miss Chen
2018年07月10日
Miss Chen

06Growing Jade Plants There are several species that are sold under the generic name jade plant. They are all Crassula species. Also called money plants or dollar plants, these are thought to bring good luck.
07Growing Kalanchoe Although there are many kinds of kalanchoe, the K. blossfeldiana is the most popular. Its sprays of bright flowers make it one of the most desired houseplants around the world.
08Growing Pencil Cactus (Euphorbia tirucalli) The pencil cactus is actually another Euphorbia species. These plants are grown for their strange, even slightly bizarre foliage.
09Growing Sempervivum Sometimes called hen and chick plants, Sempervivum succulents are some of the hardiest: hot or cold, light or shade, they can thrive. With good care, these are magnificent accent plants.
10Creating a Succulent Dish Garden Follow these simple, step-by-step instructions to creating a beautiful dish garden using succulents.
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Miss Chen
2018年07月10日
Miss Chen
Succulents seem custom-made for indoor gardeners. These hardy plants can thrive for long periods in poor conditions. But given proper care, succulents are some of the most beautiful plants in the world. Learn how to care for succulents plus a few varieties we love.
01How to Grow Healthy Succulents Succulents are some of the most rewarding plants for indoor gardeners. They're tough, beautiful, and have interesting and varied foliage. Read our best tips for caring for these plants.
02Growing Aloe Aloe is one of the most popular succulents, grown for both its beauty and health benefits.
03Growing Desert Rose (Adenium obesum) Desert rose is a striking plant with beautiful flowers. Beware the sap, however, which can be caustic.
04Growing Sedum Morganianum (Burro's Tail) These beautiful succulents are trailing plants that form long, striking "tails" of tear-drop shaped leaves.
05Growing Echeveria One of the more popular varieties, Echeveria succulents grow in tight rosettes of overlapping leaves. They are perfect indoor plants: small, beautiful and easy to care for.
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Miss Chen
2018年07月09日
Miss Chen
Description: This plant is a summer annual about 1-3' tall that is either sparingly branched or unbranched. The central stem is stout, round, light green, and more or less covered with white hairs; it also has fine longitudinal veins that are white. The alternate leaves are up to 6" long and 4" across (excluding the petioles), becoming smaller in the upper half of the central stem. They are cordate-ovate or elliptic and smooth or slightly undulate along the margins. The base of each leaf is rounded or wedge-shaped, while its tip is rounded and blunt. The lower surface of each leaf is usually pubescent, while the upper surface is less pubescent or hairless. The central stem terminates in a stout panicle of spikes with whitish green flowers. This terminal inflorescence is up to 6" long (rarely longer in large plants). There are also shorter axilllary panicles of flowering spikes or simple spikes that develop from the axils of the middle to upper leaves. The flowering spikes are bristly in appearance from the crowded flowers and pointed bracts. Rough Pigweed is usually monoecious with separate pistillate (female) and staminate (male) flowers on the same plant. The pistillate flowers have 5 pale white sepals, an ovary with 3 styles, and no petals. The staminate flowers have 5 pale white sepals, 5 stamens, and no petals. The sepals are oblong and about 3 mm. in length; their tips are either short and pointed or flattened. At the base of each flower, there are one or more green bracts about 3-6 mm. long. These bracts have long pointed tips. The blooming period occurs from late summer to early fall and lasts about 1-2 months. Cross-pollination of the flowers is by wind. Each pistillate flower develops a single seed in a membranous bladder (utricle). This utricle splits up to release the seed. Each small seed is dark brown or black, flattened, and circular; it has a smooth and shiny surface. The root system consists of a short stout taproot that is usually tinted red. This plant spreads by reseeding itself.
Cultivation: This plant is typically found in full sun, mesic to dry conditions, and a soil containing loam, clay-loam, or gravelly material. Its size can vary significantly according to moisture levels and the fertility of the soil. The seeds can remain viable in the soil for 30 years or more. Range & Habitat: The non-native Rough Pigweed is a common plant that occurs in most counties of Illinois (see Distribution Map). It is originally from South America. Habitats include degraded upland prairies, cropland, fallow fields, farm lots, gardens, gravelly areas along roads and railroads, sunny areas along the foundations of buildings, and waste areas. Highly disturbed areas are preferred.
Faunal Associations: Insects rarely visit the wind-pollinated flowers. The caterpillars of the skipper Pholisora catullus (Common Sootywing) feed on the foliage, as do the caterpillars of several moths, including Holomelina aurantiaca (Orange Holomelina), Hymenia perspectalis (Spotted Beet Webworm Moth), Spilosoma congrua (Agreeable Tiger Moth), and Spoladea recurvalis (Hawaiian Beet Webworm Moth). Sometimes Disonycha spp. (Flea Beetles) chew little holes in the leaves. The seeds of pigweeds are very popular with granivorus birds as a source of food during the fall and winter (see Bird Table). Pigs and cattle eat pigweeds readily, although the foliage can cause bloating and other symptoms of nitrate poisoning if an excessive amount of the foliage is eatened. Deer and rabbits eat pigweeds to a limited extent. Photographic Location: Along the pebbly foundation of the webmaster's apartment building in Urbana, Illinois.
Comments: Rough Pigweed is another weedy member of the Amaranth family, although its seeds are an important source of food to birds. It is quite similar in appearance to another common weed, Amaranthus hybridus (Slender Amaranth), and prefers similar habitats (perhaps those that are slightly drier). Rough Pigweed tends to be shorter and stouter in its growth habit than Slender Pigweed. The flowering spikes of Rough Pigweed are usually more stout and bristly than those of Slender Pigweed; the flowering spikes of Rough Pigweed are whitish green while in bloom, while the flowering spikes of Slender Pigweed are more green (because its sepals are less conspicuous). Using a 10x hand lense, it is possible to observe that the sepals of Rough Pigweed often have flattened tips, while the sepals of Slender Pigweed are more pointed at their tips. Furthermore, the floral bracts of Rough Pigweed are up to 6 mm. in length, while those of Slender Pigweed are up to 4 mm. in length. Red forms of Rough Pigweed apparently don't occur; reddish pigweeds are usually Slender Pigweed, or less often a cultivated Amaranth that has escaped from gardens.
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