Green第11页 - 绿手指 - 养花技巧、花生病了怎么办、花园打理和设计

2018年06月14日

Description: This biennial or short-lived perennial plant is 3-6' tall, branching occasionally. The stout stems are terete, glabrous, and sometimes glaucous; they are pale green, pink, or reddish purple, often with prominent longitudinal veins. The lower portion of the central stem is hollow. The compound leaves are odd-pinnate or doubly odd-pinnate; they alternate along the stems. The lower compound leaves are up to 1½' long and ¾' across; the upper compound leaves are much smaller. Each division of a compound leaf typically has 3-7 leaflets. The bases of petioles are partially enclosed by their sheaths; otherwise they are similar to the stems in appearance, although more slender. The glabrous leaflets are 1½-4" long and ½-1¼" across; they are oblong-elliptic with wedge-shaped bottoms, tapered tips, and dentate margins. Sometimes the leaflets fold upward along the length of their central veins. Leaflet venation is pinnate. The lateral veins of leaflets extend to the notches between the teeth, rather than to their tips, along the leaflet margins.

The upper stems occasionally produce compound umbels of small white flowers. These compound umbels are up to 6" across and consist of 10-20 umbellets. Individual umbels are dome-shaped on top, rather than flat. Individual umbellets have about 12-15 flowers that are clustered together. Each flower is about 1/8" across, consisting of 5 white petals, an insignificant calyx, 5 white stamens, and a divided style. The tiny petals are constricted at their bases, and they have notched tips. The blooming period occurs during mid-summer, lasting about 1 month. The flowers have a slight fragrance that is sometimes detectable. Afterwards, each flower is replaced by a small angular fruit containing a pair of seeds. The root system consists of several fleshy roots at the base of the plant; they are ovoid or oblongoid in shape. These fleshy roots are exceptionally poisonous; the stems and foliage are somewhat less poisonous. This plant spreads by reseeding itself into neighboring areas.

Cultivation: The preference is full to partial sun and wet to moist conditions. Some standing water is tolerated, if it is temporary. Either loamy or sandy soil is acceptable to this plant; it should contain some organic material to retain moisture. Foliar disease isn't a significant problem for healthy plants in an appropriate location.

Range & Habitat: The native Water Hemlock has been observed in nearly all counties of Illinois (see Distribution Map); it is occasional to locally common. Habitats include moist open woodlands, swamps, wet prairies, prairie swales, marshes, seeps, and roadside ditches. Water Hemlock prefers moister locations than the introduced Conium maculatum (Poison Hemlock), and so these two species rarely compete with each other for the same ecological niche. It is not uncommon to find Water Hemlock growing where Iris virginica shrevei (Blue Flag Iris) also occurs.

Faunal Associations: The exposed nectar of the flowers attract primarily insects with short mouthparts. These floral visitors include leafcutter bees (Megachile spp.), Halictid bees, cuckoo bees (Sphecodes spp.), plasterer bees (Colletes spp.), masked bees (Hylaeus spp.), Sphecid wasps, Vespid wasps, Tiphiid wasps, spider wasps (Pompilidae), velvet ants (Mutillidae), cuckoo wasps (Chrysididae), Eucoilid wasps, Braconid wasps, soldier flies (Stratiomyidae), Syrphid flies, thick-headed flies (Conopidae), Tachinid flies, flesh flies (Sarcophagidae), Muscid flies, and miscellaneous beetles (Robertson, 1929). The larvae of a butterfly, Papilio polyxenes (Black Swallowtail), feed on the foliage of Water Hemlock, while the larvae of a moth, Epermenia cicutaella, feed on the flowers and immature fruits. Several aphids suck plant juices from this plant, including Cavariella aegopodii (Carrot-Willow Aphid), Cavariella pastinacae (Parsnip-Willow Aphid), and Hyadaphis foeniculi (Honeysuckle-Fennel Aphid). Other insect feeders include Apion pensylvanicum (a weevil), Orthops scutellatus (Carrot Plant Bug), Paroxyna atlantica (Atlantic Grasshopper), and Paroxyna clavuliger (Olive-Green Swamp Grasshopper); see Pepper (1965), Blackman & Eastop (2013), Majka et al. (2007), Wheeler et al. (1983), and Harms & Grodowitz (2009). The toxic foliage and roots are usually left undisturbed by mammalian herbivores, although cattle and other livestock sometimes eat this plant with dire results. The fleshy roots are especially toxic: just a small piece can be fatal.

Photographic Location: The photographs were taken of plants in a wet prairie along an abandoned railroad in Champaign County, Illinois. There was 2 ft. of standing water around the base of the plants as the result of a recent heavy rainfall, although at other times the site is merely moist.

Comments: Water Hemlock is a reasonably attractive and eloquent plant, while the flowers provide nectar to many beneficial insects. It is fairly easy to distinguish Water Hemlock from other members of the Carrot family because of its double compound leaves and rather large leaflets that are rarely lobed. Many other members of the Carrot family have only simple compound leaves, or their leaflets are much smaller in size, or their leaflets are deeply lobed. On Water Hemlock, the lateral veins of the leaflets extend to the notches between the teeth, rather than to their tips, along the leaf margins. Apparently, no other member of the Carrot family in Illinois has this characteristic.

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2018年06月14日

Description: This perennial plant is 1½–3½' tall, branching occasionally. The stems are light green or light reddish green, glabrous, and glaucous. The compound leaves are up to 1' long and 8" across (excluding their petioles), becoming smaller as they ascend the stems; they are alternate, green, and glabrous. The lower leaves are double-pinnate, while the upper leaves are often simple-pinnate. The petioles of the lower leaves are long, while those of the upper leaves are much shorter or absent. The leaflets are up to 3" long and 1/3" (8 mm.) across; they are linear to lanceolate-linear, dentate, and sometimes cleft into narrow lobes. The axils of the upper leaves often have sessile clusters of ovoid bulblets. The upper stems terminate in compound umbels of small white flowers.

Each compound umbel spans about 2-4" across and it consists of about 8 umbellets. Each umbellet has about 16 flowers. There are neither bracts nor bractlets at the base of the compound umbel and its umbellets, although a small sessile leaf may occur near the base of the compound umbel. Each flower spans about 1/8" (3 mm.) across or a little less, consisting of 5 white petals, 5 stamens, 2 styles, and an ovary. The blooming period occurs during late summer to early autumn and it lasts about one month. There is no noticeable floral scent. A pair of seeds are contained in each fruit (schizocarp). These fruits are about 1/8" (3 mm.) long; they are somewhat flattened, ovoid-oblongoid in shape, and slightly notched at their apices. The root system consists of a cluster of elongated fleshy roots. The foliage, seeds, and fleshy roots are toxic (especially the latter). This plant reproduces by seeds and aerial bulblets.

Cultivation: The preference is light shade to full sun, wet conditions, and a mucky or mossy soil. This plant requires soil that is saturated with moisture throughout the year.

Range & Habitat: The native Bulblet-Bearing Water Hemlock is an uncommon plant that occurs primarily in the northern half of Illinois, especially in the NE area of the state (see Distribution Map). Habitats include both sandy and non-sandy marshes, swamps, and borders of lakes and ponds. This species is normally found in high quality wetlands.

Faunal Associations: Like other members of the Carrot family, the nectar of the flowers is accessible to insects with short mouthparts, therefore they will attract such visitors as flies, wasps, beetles, and small bees. Some of these insects may collect or feed on the pollen as well. The caterpillars of a butterfly, Papilio polyxenes asterias (Black Swallowtail), feed on the foliage. Other insects that feed on water hemlock species (Cicuta spp.) include stem-boring larvae of a weevil (Apion pensylvanicum), flower- and fruit-eating larvae of an Epermeniid moth (Epermenia cicutaella), flower- and fruit-eating nymphs and adults of Orthops scutellatus (Carrot Plant Bug), Cavariella aegopodii (Carrot-Willow Aphid) and other Cavariella spp., and Hyadaphis foeniculi (Honeysuckle-Fennel Aphid); see Majka et al. (2007), Covell (1984/2005), Wheeler et al. (1983), Blackman & Eastop (2013), and Pepper (1965). The poisonous seeds are not eaten by birds, while the poisonous foliage and roots are usually avoided by mammalian herbivores. Consumption of the fleshy roots and other parts of this plant by either mammalian herbivores or humans can cause convulsions and death.

Photographic Location: A sandy marsh at the Heron Boardwalk in Vermilion County, Illinois.

Comments: Bulblet-Bearing Water Hemlock is highly unusual because it bears clusters of bulblets in the upper leaf axils. With the exception of Ranunculus ficaria (Lesser Celandine), I can think of no other plant in Illinois that has this characteristic. Some Allium spp. (Onions) produce bulblets instead of flowers in their umbels, but their bulblets are not produced from the axils of leaves. Another species that occurs within the state, Cicuta maculata (Water Hemlock) is more common. Water Hemlock is a larger plant than Bulblet-Bearing Water Hemlock and it has broader leaflets (more than 1/3" or 8 mm. across). Water Hemlock blooms during mid-summer before Bulblet-Bearing Water Hemlock begins to bloom. Another white-flowered member of the Carrot family, Sium suave (Water Parsnip), often blooms at the same time as Bulblet-Bearing Water Hemlock and it occurs in the same wetland habitats. Water Parsnip has about 3 lanceolate bracts at the base of its compound umbels and its leaves are always simple-pinnate. Another similar species that blooms late, Oxypolis rigidior (Cowbane), also has leaves that are simple-pinnate. In contrast, the lower leaves of Bulblet-Bearing Water Hemlock are double-pinnate.

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2018年06月14日

Description: This herbaceous perennial plant is 1-3' tall and usually unbranched; it will form side branches if the central stem is broken. The central stem is light green, glabrous, and terete (round in cross-section); there are pairs of opposite leaves along its length that have a tendency to droop. The leaf blades are up to 6" long and 2¼" across; they are lanceolate to broadly lanceolate, hairless, and serrated along their margins. The upper surface of each leaf blade is medium to dark green, while its lower surface is pale green. At the base of each leaf blade, there is a short petiole about ¼–½" in length.

The central stem terminates in a short spike of flowers. Each flower is 1–1½" in length; it has a corolla with a flattened tubular shape and a short calyx with 5 blunt teeth. The two-lipped corolla is pink to deep rosy pink; the upper lip has the shape of a broad hood, while the lower lip has 3 outer lobes. The central lobe of the lower lip is often elevated slightly above the 2 lateral lobes when the flower is fully open. Behind the lower lip of the corolla, there is a conspicuous patch of white or pale yellow hairs. The calyx is light green and glabrous; it has teeth that are broadly ovate or oval-ovate. Underneath the calyx of each flower, there are short appressed bracts that resemble the teeth of the calyx. The blooming period occurs from late summer to early fall and lasts about a month. There is no floral scent. Ovoid seed capsules develop after the corollas of the flowers turn brown and fall off. Each seed capsule is about ½" long; it is initially light green and glabrous, but later turns brown and splits open to release the seeds. The root system is rhizomatous and vegetative colonies of plants occasionally form.
Stems & Leaves
Cultivation: The preference is partial or dappled sunlight, consistently moist conditions, and a fertile loamy soil with abundant organic matter. The foliage is rarely disfigured by disease.

Range & Habitat: The native Pink Turtlehead is an uncommon wildflower that is found primarily in southern and western Illinois; elsewhere in the state, it is rare or absent (see Distribution Map). Habitats include wet to moist floodplain forests, swamps, soggy meadows and thickets, and partially shaded seeps and springs. This species usually occurs in high quality habitats. It is sometimes grown in flower gardens.

Faunal Associations: The flowers are cross-pollinated primarily by bumblebees; sometimes the Ruby-Throated Hummingbird also visits the flowers of Chelone spp. (Turtleheads) for their nectar. The bitter foliage is usually avoided by White-Tailed Deer and other mammalian herbivores.

Comments: Pink Turtlehead is the only native Chelone sp. (Turtlehead) in Illinois with pink to deep rosy pink flowers. It is an attractive plant with turtlehead-shaped flowers. The other native Turtlehead within the state is Chelone glabra (White Turtlehead), which has white (or slightly pink) flowers and shorter petioles (less than ¼"). Sometimes Chelone lyonii (Lyon's Turtlehead) is grown in flower gardens, although it has not naturalized within the state. This species is native to the Appalachian mountains in the SE. Lyon's Turtlehead has flowers that are about the same color as those of Pink Turtlehead, but it has wider leaf blades and longer petioles (½–1½" long). Other common names that refer to Chelone obliqua include Rose Turtlehead, Purple Turtlehead, and Red Turtlehead. Plants that are offered for sale as 'Chelone obliqua' by mass-market nurseries may be hybrids of undetermined parentage, rather than the open-pollinated species.

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Description: This is a submerged or floating aquatic plant (about ½–12' long) that branches at right angles (90°). The jointed stems are pale green to reddish purple, glabrous, and fragile, often dividing into smaller segments. Along these stems, there are whorls of 5-14 divided leaves that curve upward; these leaves are 1-4 cm. long. The leaves are more crowded toward the growing tips of stems than elsewhere; they are medium to dark green and glabrous. Both stems and leaves have a tendency to be somewhat stiff and brittle, especially when they are coated with lime in calcareous water. Each leaf divides dichotomously into 2-4 segments (rarely more); these segments are narrowly linear (up to 0.5 mm. across) and flattened. Each leaf segment is conspicuously toothed along one side, while it is smooth (entire) on the other side.

Coontail is monoecious, forming male (staminate) and female (pistillate) flowers on the same plant. Both types of flowers are produced in the axils of the leaves and they are sessile. Female flowers occur individually, while male flowers occur either individually or in pairs. Both types of flowers are very small in size (about 2 mm. in length), and they have involucres consisting of 8-14 floral bracts that surround the reproductive organs. These bracts are translucent and broadly oblong; their tips are truncate and fringed. There are neither sepals nor petals. Each female flower has a single pistil with a long slender style, while each male flower has 8-14 anthers that are sessile or nearly so (very short or absent filaments). The blooming period occurs intermittently during the summer and early autumn. Cross-pollination is accomplished through water currents. However, only a few flowers, if any, are produced by individual plants. The female flowers are replaced by 3-spined achenes. The body of each mature achene is 4-6 mm. long, ovoid in shape, slightly flattened, and wingless along its sides. Each achene has 2 basal spines and a single spine at its apex; these spines are 0.5-12.0 mm. in length and they are either straight or curved. Coontail has no real root system, although it is able to anchor itself in mud or sand through either lodged stems or the development of modified leaves. By late autumn, winter turions (tight buds of leaves) develop at the tips of stems that sink to the bottom of a body of water, where they remain until spring of the following year. Growth and development begin again with the return of warmer weather. In addition to its achenes and winter turions, Coontail reproduces vegetatively whenever its stems divide into smaller segments.Distribution Map

Cultivation: The preference is full sun and relatively clear water up to 9' deep that has adequate levels of nutrients; water pH can be mildly acidic to alkaline. At the water's bottom, the soil should consist of mud, sandy mud, or muddy gravel. Coontail is more tolerant of shade than the majority of aquatic plants and it is able to tolerate some turbidity in the water if it is not excessive. This aquatic plant can adapt to sites with either stagnant water or slow-moving currents where there is some protection from wind and waves. Because of its phytotoxic properties, Coontail can inhibit the growth of phytoplankton and blue-green algae (cyanobacteria). At some locations, it can spread aggressively and become a pest.

Range & Habitat: The native Coontail is occasional to common throughout Illinois. This species is native to a wide area of North America, from where it has spread to other parts of the world. Habitats include quiet inlets of lakes, ponds, rivers with slow-moving currents, marshes, and springs. Generally, Coontail is typically found in bodies of water with muddy bottoms, although it also occurs where the water bottom contains some sand or rocky material. Sometimes Coontail is cultivated as an aquarium plant. It has also been introduced deliberately into polluted bodies of water in bioremediation projects because of its ability to absorb suspended particles of chromium, lead, arsenic, and other chemicals.

Faunal Associations: The leaves of Coontail provide hiding places for small aquatic organisms and its leaves are sometimes grazed by snails. Both the foliage and seeds of this aquatic plant are eaten by the American Coot (Fulica americana), many species of waterfowl (see the Waterfowl Table), and some turtles (Legler, 1943; Ernst et al., 1994), including the Musk Turtle (Sternotherus odoratus), Snapping Turtle (Chelydra serpentina), Blanding's Turtle (Emys blandingii), Painted Turtle (Chrysemys picta), River Cooter (Pseudemys concinna), and Slider (Trachemys scripta). This aquatic plant is also eaten by carp and, to a lesser extent, by muskrats. The foliage and seeds of Coontail can spread to new wetlands through human activity. For example, when people dump the content of aquariums into waterways that contain Coontail, it can easily establish itself in such habitats. Similarly, because Coontail can cling to anchors, boat trailers, fishing nets, and dredging equipment, it may be transported considerable distances from one body water to another.

Photographic Location: In shallow water of a sandy marsh at the Heron Boardwalk in Vermilion County, Illinois.

Comments: Coontail superficially resembles some Chara spp., even though the latter are actually algae, rather than vascular plants. Coontail can be distinguished by its leaf segments, which have teeth along only one of 2 sides (rather than both), and its crushed foliage lacks the distinctive garlic or skunk-like smell that is so typical of many Chara spp. A closely related species, Ceratophyllum echinatum (Spiny Hornwort), is also found in Illinois, but it is less common. Compared to Coontail, Spiny Hornwort has softer foliage and its leaf segments either lack teeth or they have less conspicuous teeth along one side of their leaf segments. In addition, the achenes of Spiny Hornwort are shallowly winged along their sides, and each winged side of an achene has 3-10 spiny teeth. Although they have apical and basal spines, the achenes of Coontail lack spiny teeth along their sides. Another common name of Ceratophyllum demersum is Common Hornwort.

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Description: This herbaceous perennial plant is ¾–2¼' tall and unbranched. The central stem is green, glabrous, and terete. A single well-developed leaf occurs near the base of the central stem. This leaf is 4-12" long, ¼–1½" across, and ascending; it is linear-elliptic to elliptic in shape and entire (toothless) along its margins. The leaf tapers gradually into a narrow base that is enclosed by a sheath, while its tip is narrowly acute and hull-shaped. The upper surface of the entire leaf is often slightly concave (curved inward from the margins) along its length. Both the upper and lower leaf surfaces are yellowish green to medium green and glabrous. Leaf venation is parallel. Below the well-developed leaf, there are 1-2 rudimentary leaves that are sheath-like and inconspicuous.

The central stem terminates in a spike of 2-15 flowers (rarely up to 20). The rachis of this floral spike is green to reddish purple, terete, and glabrous; it has a tendency to zig-zag between the flowers. Each flower is 1-2" across, consisting of 3 petaloid sepals, 3 petals, an exposed reproductive column, and an inferior ovary. Both the sepals and petals (excluding the petal that has been modified into a lip) are pink to deep rosy pink (rarely white); the sepals and petals may also have faint veins of dark rosy pink. The sepals are ovate or broadly oblong-ovate in shape, while the petals are broadly elliptic or elliptic-ovate in shape. Depending on the stage of development, both petals and sepals are spreading and more or less incurved from their tips; their upper surfaces are flat to somewhat concave. Both sepals and petals are nearly the same length (about ¾" long), although the sepals are a little wider. The third petal has been modified into an upper lip about ¾" long. This upper lip is linear in shape (grooved above and convex below), except toward its tip, where it has been widened by 2 lateral lobes; these lobes are half-orbicular to bluntly triangular in shape. At the center of this lobed tip, is a patch of white and a cluster of clubbed pseudo-stamens; these pseudo-stamens are hair-like in appearance and yellow to orange. Elsewhere, the lip is pink to rosy pink (rarely white) like the sepals and remaining petals. The lip is also hinged at its base.

The exposed reproductive column is mostly linear-flattened in shape, straight, and pink to rosy pink (rarely white). However, toward its tip, the reproductive column is upturned, terete along its center, and laterally lobed. The reproductive organs are located at the tip of the column, which is dark rosy pink. The reproductive column lies opposite from the upper lip of the flower; it is about ¾" long. The ascending inferior ovary, at the time of bloom, is light green to pale greenish pink, cylindrical-ribbed in shape, and glabrous. The blooming period usually occurs from early to late summer, lasting about 3-4 weeks. The flowers bloom sequentially from the bottom to the top of the floral spike. There can be either a mild floral fragrance or none. Afterwards, fertile flowers are replaced by seed capsules that are about ¾" long and ellipsoid-ovoid in shape; they eventually break open to release numerous tiny seeds, which are distributed by the wind. The root system consists of a globoid to ovoid corm with fibrous roots below.

Cultivation: The preference is full or partial sun, wet to moist conditions, and soil containing some sand and/or peat. Sometimes, this orchid is available from specialist orchid nurseries and it can be cultivated in gardens if its requirements are met. Wild plants, however, should never be collected.

Range & Habitat: The native Grass Pink Orchid has been found primarily in the northern half of Illinois and a few scattered counties elsewhere (see Distribution Map). This orchid is now rare and it is state-listed as 'endangered.' At one time, the Grass Pink Orchid was more abundant in Illinois, but its populations have declined because of habitat destruction and unscrupulous collecting. Habitats where this orchid can be found include wet to moist sand prairies, wet to moist sandy meadows, shallow sandy swales, openings in sandy swamps, fens, and bogs. This orchid is found in high quality natural areas.

Faunal Associations: Bumblebees and other large long-tongued bees are the primary pollinators of the flowers. Halictid bees, flies, butterflies, skippers, and beetles also visit the flowers occasionally, but they are unlikely to be effective at cross-pollination. See Cole (1988), Luer (1975), Small (1976), and Thien & Marcks (1972) for more information. Neither nectar nor accessible pollen are available to such flower-visiting insects. Instead, they are lured by deception to land on the showy flowers. In particular, they are often attracted to the colorful pseudo-stamens on the lip of the flower. If the visiting insect has sufficient weight, the hinged lip of the flower collapses onto its exposed reproductive column, attaching pollinia to the back of the insect. When the same insect visits the next flower, the same process can deposit the pollinia onto the exposed stigma of the reproductive column, enabling cross-pollination to occur. Like other orchids, the foliage and flowers of the Grass Pink Orchid are probably vulnerable to browsing by White-tailed Deer and other mammalian herbivores. When such animals are too abundant, it may be necessary to protect colonies and solitary plants of this orchid with wire cages or fencing.

Photographic Location: A shallow sandy swale at a nature preserve in Lake County, Illinois.

Comments: The structure of the flower for this orchid is highly unusual because its lip is located at the top rather than the bottom, causing the flower to appear upside-down (even though it is actually rightside-up). The Grass Pink Orchid is the most common species of its genus within the state and it is widely distributed within the eastern United States and SE Canada. The only other species of this genus within the state, the Oklahoma Grass Pink Orchid (Calopogon oklahomensis), is even more rare and it is also state-listed as 'endangered.' This latter orchid can be distinguished from the former as follows: 1) the petals and sepals of its flower are usually a lighter shade of pink, and 2) the lip of its flower has a patch of short pink pseudo-stamens above its showier yellow pseudo-stamens. The more common Grass Pink orchid lacks short pink pseudo-stamens on the lip of its flower. The Oklahoma Grass Pink Orchid is also found in drier habitats, like mesic prairies. Other common names of Calopogon tuberosus are Tuberous Grass Pink and Grass Pink, even though it is neither a grass nor a member of the Pink family (Caryophyllaceae).

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Description: This herbaceous perennial plant becomes 3-7' tall, forming either a solitary or a cluster of central stems that branch occasionally to abundantly. The central stems are light green, vertically veined, glabrous, and sometimes glaucous; they are terete (circular in circumference), except for the decurrent bases of the leaves. This latter characteristic causes them to appear heavily winged. Spreading to drooping alternate leaves occur along the entire length of these stems at regular intervals, becoming gradually smaller in size as they ascend. The leaves of the central stems are up to 7" long and 1½" across; they are oblong-lanceolate in shape, while their margins are entire (toothless) and often slightly wavy (vertically) or undulate (horizontally). These leaves taper gradually, forming narrow acute tips, while their bases strongly clasp the central stems. The basal margins of these leaves extend downward 1-3" along their stems, forming pairs of wings up to ¾" across. The upper leaf surface is medium to dark green and glabrous, while the lower leaf surface is a slightly lighter shade of green, glabrous, and sometimes glaucous. Leaf venation is pinnate; the central veins of these leaves are prominent, particularly toward their bases. Slender ascending lateral stems develop from the axils of the leaves, particularly along the middle to upper leaves of the central stems. The alternate leaves of these lateral stems are up to 3" long and ½" across; they are elliptic or linear-lanceolate in shape, entire along their margins, and either sessile or decurrent at their bases. When their bases are decurrent, the basal margins of these secondary leaves extend downward up to 1" along their stems, forming pairs of wings up to ¼" across.

The central stems terminate in large panicles of flowerheads (up to 2' long and 2' across) that are more or less dome-shaped. On robust plants, many lateral stems will also terminate in smaller panicles of flowerheads. The branches of these inflorescences are similar to the stems, except they are less winged from the decurrent bases of their leafy bracts. These bracts are up 3" long and ½" across and they are similar in appearance to the leaves of lateral stems, although they can become smaller in size. Each daisy-like flowerhead is ¾–1" across, consisting of 40-60 ray florets that surround a dense head of 180+ disk florets. The ray florets are pistillate (female), while the disk florets are perfect (male and female). The petaloid rays of these flowerheads are linear-oblong in shape and white (rarely lavender or light purple). The corollas of the disk florets are about 2 mm. long, yellow, tubular in shape, and 5-lobed along their upper rims. Around the base of each flowerhead, light green phyllaries (floral scales) are arranged in about 3 overlapping series. These phyllaries are linear-oblanceolate in shape, membranous along their margins, and appressed together. When the flowerhead blooms, these phyllaries form an involucre that is shaped like a shallow plate or flat disk. The peduncles (basal stalks) of these flowerheads are up to 3" long. The blooming period occurs during late summer into autumn, lasting about 1-2 months. Afterwards, the fertile florets are replaced by achenes about 1.5–2.5 mm. in length. These achenes are obovoid, somewhat flattened, and slightly winged along their margins; solitary pairs of awn-like scales occur at their apices. The achenes can be blown about by the wind or float on water. The root system is shallow and fibrous.

Cultivation: The preference is full sun, wet to moist conditions, and fertile soil containing loam, clay-loam, or silty deposits. However, this plant can adapt to drier conditions in gardens if it is watered during dry spells. Growth and development from seed is usually rapid, as this plant can bloom during the first year. Some stakes or a wire cage may be necessary to keep it upright in a flower garden or rain garden.

Range & Habitat: The Decurrent False Aster is largely restricted to several counties in central and SW Illinois, where it is found along the floodplain of the Illinois River (see Distribution Map). This species has also been found at Lake County in NE Illinois, where it is adventive. Outside of Illinois, a few small colonies of plants have been found along the floodplain of the Mississippi River in eastern Missouri. Decurrent False Aster is a rare plant that is listed as 'threatened' in Illinois, and it is also listed as 'threatened' at the Federal level of the United States. Populations of this plant can vary considerably from year-to-year depending on the pattern of precipitation and flooding along the Illinois River and Mississippi River. Flood-control projects, wetland habitat destruction, and excessive sediment in the water during floods can undermine the long-term survival of this plant. Habitats include riverbottom prairies, shallow marshes, and mud flats along major rivers. This is a conservative species that is found in wetland habitats along rivers that are prone to occasional flooding. Such floods reduce competition from other herbaceous plants and woody vegetation.

Faunal Associations: Very little is known about the floral-faunal relationships of Decurrent False Aster (Boltonia decurrens), although it is probably similar to the more common False Aster (Boltonia asteroides). Pollinators of the flowerheads probably consist of long-tongued bees, short-tongued bees, wasps, flies, butterflies, skippers, and beetles. Both nectar and pollen are available as floral rewards. One bee species, Perdita boltoniae, is a specialist pollinator (oligolege) of Boltonia spp., and another bee, Melissodes boltoniae, may be a weak oligolege of these plants (Robertson, 1929). The larvae of a beetle, Microrhopala xerene, mine the leaves of False Aster and other species in the Aster family (Clark et al, 2004). The relationship of Decurrent False Aster to vertebrate animals is probably similar to many wetland asters (Aster spp.).

Photographic Location: A flower garden in Champaign, Illinois.

Comments: This rare wildflower adapts to gardens readily and it should be cultivated more often. Decurrent False Aster (Boltonia decurrens) is similar in appearance to False Aster (Boltonia asteroides), except the latter species lacks decurrent wings along its stems. Decurrent False Aster also lacks the wandering rhizomes of the latter species, although it is capable of developing more than one shoot from its root system. Decurrent False Aster is sometimes classified as a variety of this latter species, or Boltonia asteroides decurrens. False asters (Boltonia spp.) differ from asters (Aster spp., Symphyotrichum spp., etc.) by lacking tufts of hair on the apices of their achenes. Instead, the achenes of false asters have awn-like scales in pairs. In addition, the bases of their flowerheads (involucres) are more flattened in appearance (shaped like a shallow dish or flat disk), while those of asters are more cup-like or turban-shaped (turbinate). The flowerheads of False Asters resemble those of fleabanes (Erigeron spp.), except the flowerheads of the latter bloom earlier in the year and their achenes have sessile tufts of bristly hairs.

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Pommy Mommy

I found about two dozen little green Tomatoes this morning!

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Description: This perennial plant is about 3-5' tall, branching frequently in the upper half. The green stems are glabrous, terete, and slightly ribbed. The alternate leaves are up to 6" long and ¾" across, becoming smaller and more narrow as they ascend the stems. They are narrowly lanceolate to oblanceolate, smooth along their margins, and glabrous; the uppermost leaves are linear. Each leaf tapers gradually to a short petiole-like base. The upper stems terminate in showy panicles of flowerheads; these flowerheads are produced in abundance. Each daisy-like flowerhead is about ¾" across, consisting of about 60 ray florets that surround numerous disk florets. The petaloid rays of the flowerheads are bright white and linear in shape (less often, they are slightly pink or slightly purple), while the tiny tubular corollas of the disk florets are bright yellow. Flowerheads have bases that are shallow and spreading, rather than cylindrically shaped; these bases are covered with overlapping floral bracts (phyllaries) that are light green and narrowly lanceolate in shape. The branching stalks of the panicle are similar to the stems and largely naked, except for narrow leaf-like bracts up to 1" long.

The blooming period occurs from late summer into the fall and lasts about 1 month. The florets are replaced by oblongoid achenes that are somewhat flattened; they are slightly broader at their apices than their bottoms. The apex of each achene has minute scales and a pair of bristles, although the bristles are not always present. The achenes usually fall only a short distance from the mother plant, unless they are carried about by water. The root system sometimes produces stolons that form plantlets at their tips.

Cultivation: The preference is partial or full sun, wet to moist conditions, and a fertile loamy soil. This plant can tolerate standing water for short periods of time and doesn't seem to be bothered by foliar disease to the same extent as many Aster spp. (Asters).

Range & Habitat: The native False Aster occurs occasionally in most areas of Illinois; it is slightly more common in southern Illinois than other areas of the state (see Distribution Map). Habitats include openings in floodplain forests, soggy thickets, alluvial meadows, prairie swales, marshes, and ditches.

Faunal Associations: The flowerheads attract many kinds of insects because their nectar and pollen are readily accessible. These insect visitors include long-tongued bees, short-tongued bees, wasps, flies, butterflies, skippers, moths, and beetles. A dagger bee, Perdita boltoniae, is an oligolege of Boltonia spp. Another bee that is somewhat oligolectic of these species is the long-horned bee, Melissodes boltoniae, which also visits the flowerheads of some Aster spp. False Aster is one of the host plants of a beetle, Microrhopala xerene, whose larvae mine the leaves. The ecological relationships of Boltonia spp. to vertebrate animals are probably similar to those of Aster spp. in wetland areas.

Photographic Location: A prairie swale at Meadowbrook Park in Urbana, Illinois.

Comments: False Aster has attractive foliage and flowers. Different varieties of False Aster have been described; the one that is typically encountered in the state, var. recognita, has flowerheads about ¾" across. In Cook County, var. microcephala also occurs, which has flowerheads that are ½" across or less. While Boltonia spp. (false asters) closely resemble Aster spp. (asters) in appearance, they differ from each other in the following characteristic: The achenes of false asters have minutes scales and/or a pair of bristles at their apices, while the achenes of asters have tufts of hair. As a result, the achenes of asters are carried more readily by the wind into new areas. The other false asters in Illinois are uncommon and differ from Boltonia asteroides by their leaves: Boltonia diffusa interior has linear leaves throughout, while Boltonia decurrens has leaves that are decurrent against their stems (i.e., the base or basal margins of each leaf lies along the surface of the stem).

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Description: This annual plant is about 2–3½' tall, branching occasionally. The stems are light green, reddish green, or brown; they are often ribbed and slightly to moderately hairy. The opposite compound leaves are simple-pinnate, becoming smaller as they ascend the stems. These compound leaves are up to 10" long and 6" across; they consist of 3-5 leaflets and have petioles up to 2" long. The leaflets are up to 3" long and 1" across; they are lanceolate or narrowly ovate, coarsely toothed along the margins, and hairless. These leaflets have short petioles (petiolules) or they are sessile. In addition to the opposite compound leaves, some of the upper leaves may be alternate and simple.

The upper stems terminate in a single flowerhead on a long slender stalk (peduncle). This flowering stalk is more or less hairy and may have 1 or 2 simple leaves up to 1½" long. The flowerhead is about ¾–1" across and it is subtended by 11-20 leafy bracts. These bracts are oblanceolate to linear in shape and ciliate along their margins. The flowerhead contains several tiny florets that are tightly bunched together. Each yellow disk floret is tubular in shape with 5 tiny teeth along its upper rim. The ray florets are insignificant. The blooming period occurs from late summer to fall and lasts about 1-2 months. There is no noticeable floral scent. The florets are replaced by achenes up to ¼" long. These achenes are initially yellow-green in color, but they eventually become dark brown. Each achene is oblong and flattened; it is a little broader toward the top than the bottom. At the apex of each achene, there is a pair of slender barbed awns. The root system is strongly branched and rather shallow. This plant reproduces by its achenes only.

Cultivation: The preference is full sun to light shade, wet to moist conditions, and a loamy or silty soil. Soil fertility and moisture availability can significantly influence the size of individual plants. Occasionally, the leaves are disfigured by various kinds of disease later in the year.

Range & Habitat: The native Tall Beggar's Ticks is an occasional plant that occurs in most areas of Illinois; it is uncommon or absent in the southwestern and north-central areas of the state (see Distribution Map). Habitats include openings in moist woodlands, woodland borders, areas adjacent to woodland paths, thickets and meadows in floodplain areas, marshes and seasonal wetlands, drainage ditches, and waste areas. Tall Beggar's Ticks is found in wooded areas to a greater extent than other Bidens spp., although it also occurs in sunny wetlands. Disturbed areas are strongly preferred; this species is rather weedy.

Faunal Associations: The flowers aren't very showy and attract few insect visitors. Occasionally, various bees and flies suck nectar from the disk florets. Pollen may be an occasional source of food for some of these insects. The caterpillars of the butterfly Nathalis iole (Dainty Sulfur) feed on the foliage of Bidens spp., as do the caterpillars of several moth species, including Cirrhophanus triangulifer (Goldenrod Stowaway), Epiblema otiosa (Bidens Borer Moth), Condica confederata (The Confederate), Palthis asopialis (Faint-Spotted Palthis), and Platysenta mobilis (Mobile Groundling). Various birds eat the seeds of Bidens spp. to a limited extent, including the Mallard, Ring-Necked Pheasant, Bobwhite Quail, Purple Finch, Common Redpoll, and Swamp Sparrow. The Cottontail Rabbit eats the foliage of Bidens spp. to a limited extent. The barbed achenes cling readily to the fur of mammals and the clothing of humans, which helps to distribute them into new areas.

Photographic Location: A roadside ditch along a wooded area near Judge Webber Park in Urbana, Illinois.

Comments: Tall Beggar's Ticks is often confused with Bidens frondosa (Common Beggar's Ticks) because of their similar appearance. Both species have non-showy flowerheads and they have compound leaves that are simple-pinnate. However, Tall Beggar's Ticks has 11-20 leafy bracts that surround each flowerhead, while Common Beggar's Ticks has only 7-10 leafy bracts per flowerhead. It is easy to see that the flowerhead in the upper photograph has more than 10 leafy bracts. Another species, Bidens discoidea, has even fewer leafy bracts than Common Beggar's Ticks. The barbed achenes of Tall Beggar's Ticks are very similar in appearance to those of Common Beggar's Ticks, although they are slightly larger in size. Other Bidens spp. in Illinois differ from the preceding species because they have showy flowerheads with conspicuous ray florets, and/or they have either simple leaves or compound leaves that are double-pinnate. Notwithstanding its common name, Tall Beggar's Ticks isn't substantially taller than Common Beggar's Ticks and many other Bidens spp.

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Description: This annual or biennial plant is 1-4' tall, branching occasionally. The green or reddish stems are glabrous to slightly hairy. The opposite compound leaves are odd-pinnate, dividing into 3-7 slender segments. Compound leaves are up to 8" long and 4" across; they are much wider at their bases than toward their tips. The leaflets are slightly ciliate and coarsely dentate; sometimes they are divided into narrow pointed lobes. From terminal stems, or from the axils of upper leaves, there develops from 1 to 3 flowerheads on slender and slightly hairy stalks. An individual plant may have several flowerheads in bloom at the same time. Each daisy-like flowerhead is about 2" across, consisting of 8-10 ray florets that surround numerous disk florets. The tiny corollas of the disk florets are tubular in shape and golden yellow, while the petaloid rays are bright yellow and oblong-elliptic in shape. Each flowerhead is subtended by 12-18 green outer bracts (phyllaries) that are each about ¾" long, linear in shape, coarsely ciliate, and rather contorted. Less visible, there are also several inner bracts that are pale yellow and lanceolate in shape. The blooming period occurs from late summer to early fall, lasting about 1-2 months. The flowers are slightly fragrant, which becomes quite noticeable in a large colony of plants. The dark brown achenes are rather flat and rough-textured with central longitudinal ridges; they are about 1½–2 times as long as they are wide. These achenes lack significant awns at their apices. The root system consists of a shallow branching taproot.

Cultivation: The preference is full sun and wet to moist conditions. The soil should be rich in organic material. This plant is easy to grow, but tends to be aggressive at a disturbed site that is sunny and moist. It can form large colonies by reseeding itself. This species of Bidens appears to have some tolerance of hot dry weather.

Range & Habitat: Long-Bracted Tickseed Sunflower is occasional in the southern half of Illinois and NE Illinois, but it is rare or absent in the remaining northern counties (see Distribution Map). This plant is native. Habitats include moist prairies, prairie swales, low areas along ponds and streams, gravelly seeps, ditches along railroads and roadsides, muddy fields, and miscellaneous waste areas. It usually occurs in or around poorly drained areas that are prone to standing water, or near sources of more or less permanent water. Disturbed areas are favored because of reduced competition from deep-rooted perennial plants.

Faunal Associations: The flowerheads are popular with many kinds of insects, including long-tongued bees, short-tongued bees, wasps, flies, butterflies, skippers, and beetles. Typical bee visitors include bumblebees, cuckoo bees (Epeolus spp., Coelioxys spp.), long-horned bees (Melissodes spp.), leaf-cutting bees (Megachile spp.), green metallic bees, plasterer bees (Colletes spp.), and Andrenid bees (Calliopsis spp., Heterosarus spp.). The caterpillars of the butterfly Nathalis iole (Dainty Sulfur) are known to favor the foliage of Bidens spp. as a food source. The caterpillars of several moths feed on the foliage, flowerheads, or the pith of stems, including Epiblema otiosana (Bidens Borer Moth), Condica mobilis (Mobile Groundling), Condica confederata (The Confederate), Cirrhophanus triangulifer (Goldenrod Stowaway), and Palthis asopialis (Faint-Spotted Palthis). Other insect feeders include leaf beetles (Calligrapha spp.), larvae of the fruit fly Icterica seriata, and several aphid species.

The seeds are eaten by small rodents and various birds, including the Ring-Necked Pheasant, Bobwhite, Swamp Sparrow, and Purple Finch. The foliage is eaten occasionally by the Cottontail Rabbit. Even though their awns are tiny or absent, the achenes of Bidens polylepis can cling to the the fur of animals or clothing of humans; this is largely because of their rough edges. Small rodents can carry the achenes to their dens for some distance from the mother plants.

Photographic Location: The photographs were taken at a prairie swale in Meadowbrook Park, Urbana, Illinois.

Comments: This is one of the more pretty and drought-tolerant Bidens spp. that occasionally strays from wetlands to moist prairies. Long-Bracted Tickseed Sunflower can be distinguished from other Bidens spp. by its attractive flowers and slender pinnate foliage. It has a very similar appearance to Bidens aristosa (Tickseed Sunflower). However, the flowerheads of this latter species are individually subtended by 8-10 outer bracts (phyllaries); these bracts are shorter, less hairy, and less contorted than those of Bidens polylepis. The achenes of Bidens aristosa usually have pairs of conspicuous awns at their apices, otherwise they are very similar in appearance to those of Bidens polylepis. However, a rare variety of the Tickseed Sunflower, Bidens aristosa mutica, also has achenes that lack significant awns. Because of its distinct outer bracts and awnless achenes, Long-Bracted Tickseed Sunflower is usually classified as a distinct species (Mohlenbrock, 2002). Scientific synonyms of this species are Bidens aristosa retrorsa and Bidens involucrata.

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Description: This annual plant is 1-3' tall, branching occasionally in the upper half. The stems are glabrous or they have a few scattered white hairs; they are often purple in bright sunlight, otherwise light green or reddish green. The compound leaves are usually odd-pinnate, consisting of 3 or 5 leaflets. Often, there are simple leaves near the flowerheads. These leaves occur oppositely along the stems, although some of the upper leaves may be alternate. The compound leaves have long petioles. The leaflets are up to 3" long and 1" across. They are lanceolate, coarsely serrated, and usually hairless, although their lower surface may be slightly pubescent. The tips of the leaflets are rather long and pointed. Some of the upper stems terminate in individual flowerheads about ¾–1" across on long stalks; some stalks may have 1-2 additional flowerheads that are smaller in size. The flowerheads consist of numerous disk florets that have golden yellow corollas; petaloid rays are absent. The flowerhead bases are surrounded by 6-10 leaf-like outer bracts (phyllaries); they are usually 8 in number. These narrow bracts are green and slightly ciliate. The blooming period occurs from late summer to early fall, lasting about 1-2 months. There is no noticeable floral scent. The dark achenes are flattened, each one terminating in a pair of long and slender awns. These awns have tiny barbs that point downward. Because of their light weight, the achenes can be blown about by wind. The root system consists of a shallow taproot that branches frequently. During the autumn, the leaves often turn purple.

Cultivation: The preference is partial to full sun and moist conditions; light shade is also tolerated. The soil should be reasonably fertile, with sufficient organic material to retain moisture. Occasional flooding and poor drainage is tolerated, if not preferred. This plant is easy to grow, often becoming a weedy pest. Sometimes it is found in more mesic situations, but individual plants will be smaller in size and less robust.

Range & Habitat: The native Common Beggar-Ticks occurs in most counties of Illinois, and it is quite common; official records probably underestimate its distribution in some areas (see Distribution Map). Habitats include moist areas of black soil prairies, moist meadows near woodlands or rivers, openings in floodplain woodlands and young flatwoods, thickets, marshes, swamps, seeps, borders of ponds or lakes, poorly drained areas along railroads and roadsides, both cultivated and abandoned fields, banks of drainage canals, and miscellaneous waste areas. This plant likes disturbed areas.

Faunal Associations: The nectar of the flowers attract fewer insects than Bidens spp. with showier flowers. Occasionally, they are visited by bumblebees, Halictid bees, wasps, bee flies, Tachinid flies, small butterflies, and other insects. The caterpillars of several species of moths feed on the foliage, pith of the stems, or flowerheads, including Epiblema otiosana (Bidens Borer Moth), Platysenta mobilis (Mobile Groundling), Condica confederata (The Confederate), Cirrophanus triangulifer (Goldenrod Stowaway), and Palthis asopialis (Faint-Spotted Palthis). Other insects that feed on this plant include the leaf beetles Calligrapha bidenticola and Calligrapha californica, larvae of the leaf-miner flies Chromatomyia syngensiae and Phytobia allecta, and several aphid species. The seeds are eaten by small rodents and various birds, including the Ring-Necked Pheasant, Bobwhite, Swamp Sparrow, and Purple Finch. The Cottontail Rabbit occasionally eats the foliage. The awns of the seeds readily cling to the fur of animals and clothing of humans, thereby spreading this plant far and wide.

Photographic Location: The photographs were taken near a drainage ditch at Judge Webber Park in Urbana, Illinois.

Comments: This is one of the more common Bidens spp. The species in this genus can be divided into two groups: those with showy flowers and those with non-showy flowers. Common Beggar-Ticks is a member of the latter group. The non-showy Bidens spp. in Illinois can be distinguished from each other by considering two characteristics: 1) whether most of the leaves are simple or pinnately compound, and 2) the number of outer bracts surrounding the flowerheads. Common Beggar-Ticks has pinnately compound leaves and about 8 outer bracts surrounding its flowerheads. It is quite similar in appearance to Bidens vulgata (Tall Beggar-Ticks), except that this latter plant has about 13 outer bracts surrounding its flowerheads.

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Description: This herbaceous plant is a summer annual about 1-2½' tall that branches occasionally to frequently. The terete to slightly angular stems are light green, purplish green, or purple, and they are glabrous. Pairs of opposite trifoliate leaves occur along these stems, although some of the uppermost leaves are usually simple and alternate. The trifoliate leaves are up to 4" long and 3" across in outline, while their petioles are up to 1½" long. The petioles are light green to purplish green and mostly glabrous, except for some sparse pubescence along the narrow grooves of their upper sides. The terminal leaflets are about 1½-2" long and ½-¾" across; they are narrowly lanceolate to lanceolate in shape and coarsely dentate along their margins. The petiolules (basal stalklets) of terminal leaflets are about ¾" long and slender. The lateral leaflets are about 1-1½" long and ½-¾" across; they are lanceolate in shape and coarsely dentate along their margins. The petiolules of lateral leaflets are very short (up to 3 mm. long). The upper surfaces of leaflets are medium green and glabrous, while their lower surfaces are pale green and glabrous (or nearly so). During autumn, the leaflets often turn purple in response to cold weather.

Upper stems terminate in either individual or small clusters of 2-3 flowerheads. The peduncles of these flowerheads are relatively short (up to 12 mm. or ½" long). Each flowerhead is about 3-6 mm. across (excluding the outer bracts), consisting of 10-20 disk florets and no ray florets. The corollas of disk florets are yellow, short-tubular in shape, and 5-lobed; they are about 3 mm. long. Originating from the base of each flowerhead, there are 2-5 leafy outer bracts. The outer bracts are medium green, narrowly oblanceolate or elliptic in shape, and glabrous (or nearly so); they are up to 1½" (4 cm.) long and 8 mm. across (usually about one-half the maximum size, but highly variable). Around the base of each flowerhead, there are several inner bracts. These inner bracts are 4-6 mm. long, light green or yellowish green, oblong-ovate in shape, and appressed together in a slightly overlapping single series. The blooming occurs from late summer into the fall, lasting about 1½-2 months. In the absence of cross-pollination, the disk florets are self-fertile. Afterwards, the disk florets are replaced by achenes with pairs of awns. The achenes (excluding their awns) are about 4 mm. long, 1-1.5 mm. across, and flattened-oblanceoloid in shape; they are truncate at their apices, while their outer sides have faint midribs. The barbed awns of these achenes (2 awns per achene) are about 1 mm. in length. Mature achenes are greenish brown to dark brown.

The root system is shallow and fibrous. This plant reproduces primarily by reseeding itself. The lower nodes of its stems can develop rootlets when they contact moist ground. Occasionally, colonies of plants of variable size will develop at favorable sites.

Cultivation: The preference is full or partial sun, wet to moist conditions, and soil containing loam or decaying organic material. Sometimes this plant establishes itself on fallen logs or the lower trunks of trees. Standing water is tolerated if it is temporary.

Range & Habitat: The native Swamp Beggar's Ticks is occasional in southern and central Illinois, while in the northern section of the state it is rare or absent (see Distribution Map). Habitats include swamps, banks of lakes, margins of ponds, low areas along rivers, and limestone sinkholes. This plant can be found in either disturbed or higher quality wetlands, favoring humid areas where there is some protection from the wind.

Faunal Associations: The non-showy flowerheads attract relatively few insect pollinators, although sometimes bees (including Halictid bees) and flies (including Syrphid, Tachinid, and bee flies) will either collect or feed on the nectar and pollen. In general, the foliage, stems, and other parts of Bidens spp. are a source of food for such insects as aphids (including Aphis coreopsidis & Brachycauda helichrysi), larvae of the fruit fly Icterica seriata, larvae of the leaf-mining flies Chromatomyia syngenesiae and Phytobia allecta, caterpillars of the butterfly Nathalis iole (Dainty Sulfur), larvae of several moths (including Cirrhophanus triangulifer and Epiblema otiosana), and leaf beetles (Calligrapha bidenticola & Calligrapha californica). See the Insect Table for a more complete listing of these species. The achenes or seedheads of Bidens spp. are consumed by some species of waterfowl, upland gamebirds, and songbirds, including the Mallard, Wood Duck, Greater Prairie Chicken, Ring-Necked Pheasant, Bobwhite Quail, Purple Finch, Common Redpoll, and Swamp Sparrow (Martin et al., 1951/1961; Havera, 1999; Schwartz, 1945). In addition, the Snapping Turtle (Chelydra serpentina), Blanding's Turtle (Emys blandingii), and the Painted Turtle (Chrysemys picta) sometimes feed on the seeds and possibly the foliage of these plants (Lagler, 1943; Ernst et al., 1994). The foliage is browsed sparingly by White-Tailed Deer and the Cottontail Rabbit. The awned achenes can cling to the feathers of birds, the fur of mammals, and the clothing of humans, which spreads Swamp Beggar's Ticks and other Bidens spp. to new locations.

Photographic Location: Border of a lake at Walnut Point State Park in Douglas County.

Comments: This is one of the Bidens spp. in Illinois with non-showy flowerheads because it lacks ray florets. Species in this group are often referred to as "Beggar's Ticks." Once the flowerheads are produced, Swamp Beggar's Ticks (Bidens discoidea) is fairly easy to distinguish from two similar species with 2-awned achenes, namely Common Beggar's Ticks (Bidens frondosa) and Tall Beggar's Ticks (Bidens vulgata). Most noticeably, the flowerheads of Swamp Beggar's Ticks have fewer outer bracts (typically 3-4) than those of Common Beggar's Ticks (typically 6-11) and Tall Beggar's Ticks (typically 13-20). In addition to having fewer outer bracts than these species, it also has smaller achenes with shorter awns. In contrast to the preceding species, other non-showy Bidens spp. in Illinois, such as Purple-Stemmed Tickseed (Bidens connata) and Three-Lobed Beggar's Ticks (Bidens comosa), can be distinguished from the preceding species by their 3- or 4-awned achenes. Sometimes Nodding Bur-Marigold (Bidens cernua) also lacks ray florets, but it has only simple leaves and its achenes are 4-awned. In comparison to the preceding Bidens spp., Swamp Beggar's Ticks has a rather delicate appearance because of its thin leaves and relatively small size.

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2018年06月10日

Description: This is a slender, but erect, herbaceous perennial plant that is up to 5' tall. It branches occasionally along the upper half of its length. The green to reddish stems are four-angled, often with white appressed hairs. The opposite leaves are up to 6" long and 1" across. They are lanceolate, conspicuously veined, and their petioles are short. Leaf margins are coarsely serrated. The upper stems terminate in panicles of flowering spikes up to 1' long and about one-half as much across. Individual floral spikes are up to 5" long, and densely crowded all around with numerous blue-violet flowers. Individual flowers are up to ¼" long and similarly across. Each flower has a blue-violet corolla with 5 spreading lobes, a short-tubular calyx with 5 narrow teeth, 4 inserted stamens, and a pistil. The calyx is grayish green to dark red and about one-half as long as the corolla. The blooming period occurs from mid- to late summer, lasting about 1–1½ months. There is no noticeable floral scent. Afterwards, the flowers are replaced by small nutlets (4 nutlets per flower). These nutlets are up to 2 mm. long, reddish brown, and oblongoid in shape. The root system is fibrous and rhizomatous. Small clonal colonies of plants are often produced from the rhizomes.
Floral Spikes

Cultivation: The preference is full to partial sunlight, moist conditions, and soil consisting of fertile loam or wet muck. This plant tolerates standing water if it is temporary. This is a good plant to locate near a small river or pond in a sunny location.

Range & Habitat: Blue Vervain occurs in every county of Illinois (see Distribution Map), where it is fairly common and native. Habitats include riverbottom prairies, moist meadows in floodplain woodlands, soggy thickets, borders of rivers and ponds, marshes, ditches, fence rows, and pastures. This plant adapts readily to degraded wetlands and other disturbed areas, but it can be found in higher quality habitats as well.

Faunal Associations: The flowers of Blue Vervain attract many kinds of long-tongued and short-tongued bees, including honey bees, bumblebees, cuckoo bees (Triepeolus spp.), digger bees (Melissodes spp.), Halictid bees, and dagger bees (Calliopsis spp.), including the oligolectic Verbena Bee (Calliopsis verbenae). These bees seek primarily nectar, although some species collect pollen. Other floral visitors include Sphecid wasps, Vespid wasps, Syrphid flies, bee flies (Exoprosopa spp.), thick-headed flies (Physocephala spp.), small butterflies, skippers, and moths (Robertson, 1929). Other insects feed on the leaves and other parts of Blue Vervain and other Verbena spp. Examples of such insects include both adults and larvae of a flea beetle (Longitarsus suspectus), larvae of the Vervain Leaf Midge (Clinodiplosis verbenae), the Verbena Aphid (Macrosiphum verbenae), leaf-eating larvae of the Verbena Moth (Crambodes talidiformis), and larvae of the Verbena Bud Moth (Endothenia hebesana); see Clark et al. (2004), Felt (1917), Thomas (1877), Covell (1984/2005), and Miller (1987). Mammalian herbivores usually avoid eating this plant because of its bitter leaves – an exception is the Cottontail Rabbit, which may eat the foliage of young plants to a limited extent. Also, various songbirds occasionally eat the seeds, including the Cardinal, Swamp Sparrow, Field Sparrow, Song Sparrow, and Slate-Colored Junco (Martin et al., 1951/1961). Experimental studies have shown that these seeds can pass undamaged through the digestive tracts of cattle, therefore they are probably distributed to some extent by these seed-eating birds.

Photographic Location: The photographs were taken at Meadowbrook Park in Urbana, Illinois.

Comments: The flowers are often a pretty shade of blue-violet, but they are small in size. Among the various Verbena spp. in Illinois, Blue Vervain (Verbena hastata) is easy to identify because it is the only vervain with elegant spikes of flowers in this color range. Other Verbena spp. within the state, excluding introduced cultivated species, have white, pink, or lavender flowers.

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