Showing 181–198 of 372 results

Filtered (372)
Bird's-foot trefoil produces whorls of 3-8 flowers on the end of long stalks that arise from leaf axils. Individual flowers are bright yellow (sometimes tinted with orange), about 1/2-3/4" long and across, in the standard pea-like pattern — a single vertical petal (the standard), a pair of lateral petals (the wings) and two petals perpendicular to the standard fused for about half their length (the keel). The calyx has long, light-green teeth. There are 10 stamens (of two lengths, alternating) and a single curved style, hairy at the tip. The fruit is an 1" long, purplish-brown, pea-like pod containing about two dozen seeds with the calyx at one end and a long "beak" (the remnant of the pistil) at the other.

Lotus

Lotus corniculatus

bird's-foot trefoil [Blooms: Jun-Sep]

Wild lupine is Illinois' only native lupine. The plant is small (1-2.5' tall) with light- to reddish-green stems with a grey cast from profuse short hairs (as are the leaves and leaf petioles). The flowers are blue-violet, typical pea-like flowers ~3/4" long, similar in structure to wild indigo flowers (five petals — a banner, two wings, and two keels). The fruits are 1-2" long, hairy pea-like seed pods, black when mature. The palmately-compound leaves with such a profusion of leaflets are distinctive. Wild lupine is the only known host plant for the caterpillars of the Karner Blue Butterfly (Lycaeides melissa samuelis), a federally listed endangered species.

Lupinus

Lupinus perennis

wild lupine [Blooms: May-Jun]

In common wood-rush (Luzula multiflora), culms terminate in umbels of 3-12 distinct flower clusters with green, hairless floral stalks ("rays") 1/2-3" long. The rays diverge by less than 60° from each other. (Which distinguishes this species from another Illinois species, hedgehog wood-rush (L. echinata), in which the rays diverge at greater angles.) A single flower cluster is roughly cylindrical, about 1/4" across and 1/4-1/2" long containing 6-16 flowers. Individual flowers are about 1/4" across and consist of six brownish, scaly, lance-shaped tepals 2.5-4 mm long with white, membranous margins; six stamens with bulky, pale-yellow anthers; and a single pistil with three feathery stigmas. The flowers are wind pollinated. Seed capsules are egg-shaped with a short beak and three longitudinal lobes; each lobe contains a single seed. A pair of leaf-like bracts up to 2" long is present at the base of the inflorescence. Blooms are present for only a week or 10 days in April. Common wood-rush is usually found in shaded upland areas but is present in Jackson Park in the meadow north of West Lagoon.

Luzula

Luzula multiflora

common wood-rush [Blooms: Apr]

Winged loosestrife is a native species that has a central stem up to 3' tall, much more modest that its notorious cousin, purple loosestrife. The stem is four-sided, narrowly winged, and largely hairless; wings run along the stem but are interrupted at the leaf nodes. The inflorescence is a spike up to 1.5' long; the flowers develop singly or in pairs from the axils of bracts on the inflorescence. Each flower is pale lavender or purple and smaller than the flowers of purple loosestrife (1/4-1/2") but otherwise superficially similar — pale purple or lavender, six wrinkled petals with a medial purple stripe, six stamens. The light green, narrow calyx is about as long as the petals, has six (not five) lance-shaped teeth, and bold longitudinal stripes. The style may or may not protrude from the corolla — the flowers are distylous so the styles may either lie just inside the flower throat or protrude well outside; the style has a fuzzy, green, globular stigma. The fruit is a capsule that develops in the remnants of the calyx. Winged loosestrife prefers wet soils and is a less showy plant than purple loosestrife, but it is a native plant that plays nicely with its neighbors.

Lythrum

Lythrum alatum

winged loosestrife [Blooms: Jun-Aug]

False Solomon's seal's stem terminates in a flattened panicle of hairy, whitish-green stalks about 3-5" long and 2" across bearing 20-80 white flowers. The individual flowers are bright white, about 3/16" across with six narrow, spreading, strap-like tepals that are shorter than the stamens, six stamens with triangular white filaments and pale yellow or cream-colored anthers, and a single central style on top of a globose ovary. The fruit is a spherical berry, initially whitish in color, turning mottled red and later bright, translucent-red (like a currant) when ripe. It can be a bit tricky to distinguish false Solomon's seal from starry false Solomon's seal, especially early in the spring when the plants are small. Two features help: the inflorescence of false Solomon's seal is two to three the size (in linear dimensions and number of flowers) as that of starry false Solomon's seal, and the stigma of false Solomon's seal is two- or three-lobed and sessile (rests directly on the ovary), while the stigma of starry false Solomon's seal is elevated on a long style (as long as the stamens). In Jackson Park, false Solomon's seal is very tolerant of woodland habitats.

Maianthemum

Maianthemum racemosum

false Solomon's seal [Blooms: Apr-Jun]

Starry false Solomon's seal stems terminate in a 1-4" long cluster (a raceme) of up to 20 white flowers, each ~3/8" across. Individual flowers have six narrow, spoon-shaped tepals longer than the stamens, six stamens with creamy-yellow anthers, and a vase-shaped pistil with a stout style. The fruit is a 1/4" diameter berry, initially green with dark stripes, becoming bright red with maturity. The leaves of Maianthemum stellatum are much narrower than those of Maianthemum racemosum (false Solomon's seal) or Polygonatum biflorum (Solomon's seal) and has an overall appearance more like a lily than a Solomon's seal (false or smooth). It can be a bit tricky to distinguish false Solomon's seal from starry false Solomon's seal, especially early in the spring when the plants are small. Two features help: the inflorescence of false Solomon's seal is two to three the size (in both linear dimensions and number of flowers) as that of starry false Solomon's seal, and the stigma of false Solomon's seal is two- or three-lobed and sessile (rests directly on the ovary), while the stigma of starry false Solomon's seal is elevated on a long style (as long as the stamens). In Jackson Park, false Solomon's seal is very tolerant of woodland habitats; starry false Solomon's seal prefers sunnier habitats like open grasslands.

Maianthemum

Maianthemum stellatum

starry false Solomon's seal [Blooms: Apr-May]

Siberian crabapple (Malus baccata) is an exotic tree that is native to cold-temperate habits throughout Asia and has been widely planted as an ornamental in the U.S. The flowers occur in groups of 4-6. Individual flowers are 1.25" across; they have five reddish-green, lance-shaped sepals; five white, circular petals with a narrow (1-2 mm) base ("claw") attaching them to the rest of the flower; 15-20 white stamens, each 7-9 mm long with a yellow to tan anther; and five (sometimes four) green styles that are slightly longer (8-10 mm) than the stamens that have globose stigmas at their tips. The fruits (pomes) are red or yellow crabapples about 5/8" in diameter; both humans and birds find them edible.

Malus

Malus baccata

Siberian crabapple [Blooms: Apr-May]

Prairie crabapple produces clusters of 2-6 flowers on the tips of the spurs and twigs. The flowers are 1-2" across with a green, hairy, cup-shaped calyx with five narrow, triangular teeth; five white or (usually) light-pink, oval petals tapering to very narrow bases; 10-20 stamens with yellow anthers; and five robust styles. The fruits are typical crabapples about 1-1.5" across with the calyx persistent, greenish-yellow and waxy when mature; the flesh is firm but sour-tasting.

Malus

Malus ioensis

prairie crabapple [Blooms: Apr-May]

Common mallow flower stalks arise from the leaf axils. They are 1/2-1" long, attached to one to three, 1/4-1/2" wide flowers. Individual flowers have a green calyx with five pointed, triangular lobes half the length of the petals; white or pale violet squared-off petals with a shallow notch and pale violet lines; the 12-15 stamens make a bumpy, white globe around the 12-15 fused pink styles in the middle of the flower, with the inner surface of the style tips as the stigmas. The fruit is a round, flattened ovoid with radiating lines (the edges of the carpels) around a dimpled center, nestled in the remains of the calyx. Some people claim that the fruit resembles a wheel of cheese (thus one of the common names); it reminds me more of a miniature gourd. All parts of this plant are edible.

Malva

Malva neglecta

common mallow [Blooms: May-Oct]

Wild chamomile stems terminate in a daisy-like flowerhead, 1-2" across. Flowerheads consist of 10-25 white, fertile (pistillate) ray florets that tend to droop slightly and a gumdrop-shaped central mass of 250-550+ yellow disk florets with both male and female reproductive structures. Individual disk florets are tubular. Behind the flowerhead are one to three series of light green, lance-shaped bracts with membranous edges. Wild chamomile can be distinguished from similar plants like ox-eye daisy (Leucanthemum vulgare) by its multiply-pinnate, slender lobes leaves and the fact that the flowerhead is actually hollow; when crushed they produce a pleasant, fruity fragrance. Wild chamomile is closely related to pineapple weed (Matricaria discoidea) but the two can't be confused.

Matricaria

Matricaria chamomilla

wild chamomile [Blooms: May-Jun]

Pineapple-weed, unlike it's cousin wild chamomile (Matricaria chamomilla), is probably native to North America, specifically the Pacific Northwest, but has spread widely both here and in Europe. It is a small plant (up to 12" tall); the stems branch frequently. Flowerheads sit on 1/2-1.5" long flower stalks that arise from leaf axils. Each flowerhead is a gumdrop-shaped or conical mass about 8 mm across of greenish-yellow disk florets (125-535+) with four tiny lobes at the apex of the tubular corolla; there are no ray florets. The bracts behind the flowerhead have papery edges. When crushed, both the flowerheads and the foliage give off a pineapple-like fragrance. Sources differ on the biogeography of this plant. Both the USDA Plants and NatureServe Explorer websites say it is an exotic in North America; Wikipedia, the Flora of North America, World Flora Online, and the Illinois Wildflowers website say it's native to North America. Like wild chamomile, the flowerheads of pineapple-weed can be used to make a tea.

Matricaria

Matricaria discoidea

pineapple-weed [Apr-Jul]

Black medic flowerheads are ball-shaped, 1/4-3/8" across, and composed of 10-30 yellow flowers, each about 1/8" long; the flowerheads arise from leaf axils and have a 1-2" long peduncle. Individual flowers are pea-like with the upper petal (the standard) not grooved and oriented perpendicular to the lower component (the keel); the two lateral petals partially cover the keel. The flowers are very similar to those of least hop clover (Trifolium dubium), but that species has a grooved standard that is bent over to act as a hood over the keel.

Medicago

Medicago lupulina

black medic [Blooms: May-?]

White sweetclover flowers occur in spikes along 2-6" long flower stalks that arise from upper leaf axils and on the terminal upper stems. Individual flowers are small (~1/4-3/8" long), have a tubular, light green calyx with five teeth, and five white petals in the typical pea-like configuration (a single standard on the top — here, hood-like over the keel, two lateral wings, and a pair of petals fused to form a medial keel that is perpendicular to the banner). The stamens and style are hidden within the keel. Yellow sweet-clover is nearly identical to white sweet-clover (Melilotus albus) except for flower color, but blooms slightly earlier. In both yellow and white sweet-clover, the "teeth" along the distal margins of the leaflets are actually sharply-pointed extensions of the secondary (pinnate) veins. A similar extension of the central vein occurs in yellow sweet-clover but is ABSENT in white sweet-clover, permitting discrimination between the two species even when not in bloom if the vein extensions are present elsewhere on the leaflet.

Melilotus

Melilotus albus

white sweetclover [Blooms: Jun-Sep]

Yellow sweetclover flowers occur in spikes along 6" long flower stalks that arise from upper leaf axils and on the terminal upper stems. Individual flowers are small (~1/4-3/8" long), have a tubular, light green calyx with five teeth, and five yellow petals in the typical pea-like configuration (a single standard on the top (here, often hood-like over the keel), two lateral wings, and a pair of partially-fused keels in the typical pea-like configuration. The stamens and style are hidden within the keel. Yellow sweet-clover is nearly identical to white sweet-clover (Melilotus albus) except for flower color, but blooms slightly earlier. In both yellow and white sweet-clover, the "teeth" along the distal margins of the leaflets are actually sharply-pointed extensions of the secondary (pinnate) veins. A similar extension of the central vein occurs in yellow sweet-clover but is ABSENT in white sweet-clover, permitting discrimination between the two species even when not in bloom if the vein extensions are present elsewhere on the leaflet.

Melilotus

Melilotus officinalis

yellow sweetclover [Blooms: Jun-Jul]

Virginia bluebells' upper stems terminate in drooping cymes of flowers. Individual flowers are 3/4-1" long with a 1/4" long, greyish-green calyx with five elliptical teeth that cups a tubular region of the corolla about 2/3 the length of the flower that in turn flares into a bell-like shape, often slightly wrinkled, with five very shallow lobes. There are five stamens with blue filaments and white anthers inside the corolla that do not emerge from the bell, the anthers reaching just past the throat; the single long, slender, white style often protrudes well beyond the margin of the bell. Virginia bluebells are pollinated by a variety of long-tongued animals including hummingbird moths (Hemaris thysbe). The fruits are four-lobed, yellow or greenish-yellow, containing four nutlets; the fruit is nestled in the flower calyx. Nothing in Jackson Park looks like Virginia bluebells; once you've identified one, you'll be confident of your ID ever afterward. For me, they are the real herald of spring, and they make me smile.

Mertensia

Mertensia virginica

Virginia bluebells [Blooms: Apr-May]

White mulberry is species that was introduced (from Asia) in the 1600's in an attempt to established a silkworm industry in North America; it has since escaped cultivation. Individual trees are usually either male (with staminate florets in drooping, whitish to yellow-green catkins 1-1.5" long) or female (with pistillate florets in less obvious green, erect, cylindrical catkins 1.3-3/4" long), but trees that produce both male and female florets are known. Male florets are 1/4" long with a tiny green or yellowish four-lobed calyx, four stamens, and no pistil or petals. (BTW, the pollen is released by mechanically flinging it into the air via the catapult-like stamens. See Taylor et al. 2006. Sex. Plant. Reprod. 19: 19–24.) Female florets are 1/4" long with a tiny green four-lobed calyx, a single, flattened-oval ovary with two diverging white or reddish styles and no stamens or petals. The fruit is a blackberry-like compound drupe that typically changes color from green to white, but some trees have fruit that continues maturation to red and finally to black. (Those producing black fruit are often referred to var. tartarica, but that name is invalid.) White mulberry can be usually be distinguished from black mulberry by the leaves; the underside of white mulberry leaves is invariably hairless and the top surface smooth, but the underside of red mulberry leaves is covered with small hairs and the upper surface is rough. However, white and red mulberry can hybridize, which can confuse matters significantly.

Morus

Morus alba

white mulberry [Blooms: Apr-May]

Red mulberry is a native (not introduced) species that is easily confused with white mulberry (Morus alba). Red mulberry forms substantial trees 30-60' tall; it is less common in Jackson Park that white mulberry. The trunk is short with greyish-brown bark; the bark is divided into strips by shallow vertical furrows. The leaves are alternate, 4-7+" long and 3-5" across, oval or egg-shaped in outline with serrated margins and a sharp tip. The leaves can either be a simple oval with a pointed tip or a two to three (rarely five) lobed leaf with a pointed terminal lobe; the unlobed leaves are more common. Individual trees are usually either male (with staminate florets in drooping, whitish to yellow-green catkins 3/4-2" long) or female (with pistillate florets in less obvious green, erect, cylindrical catkins 3/4" long), but trees that produce both male and female florets are known. Male florets are 1/4" long with four light green sepals, four stamens, and no pistil or petals. (BTW, the pollen is released by mechanically flinging it into the air via the catapult-like stamens.) Female florets are 1/4" long with four light-green sepals, a single, flattened-oval ovary with two white to reddish, sessile stigmas and no stamens or petals. The fruit is a blackberry-like compound drupe that typically changes color from green to red to finally purplish-black with maturation. White mulberry can be usually be distinguished from black mulberry by the leaves; the underside of white mulberry leaves is invariably hairless and the top surface smooth, but the underside of red mulberry leaves is covered with small hairs and the upper surface is rough. However, white and red mulberry hybridize, which can confuse matters significantly. Leaves may be lobed, but less commonly than in white mulberry. White mulberry can be usually be distinguished from black mulberry by the leaves; the underside of white mulberry leaves is invariably hairless and the top surface smooth, but the underside of red mulberry leaves is covered with small hairs and the upper surface is rough. However, white and red mulberry can hybridize, which can confuse matters significantly.

Morus

Morus rubra

red mulberry [Blooms: ??]

Glade mallow flowers fill the entire apex of the plant in multiple clusters (panicles). Each plant produces only male or only female flowers. Both male and female flowers are about 1/2-3/4" across with 1" long pedicels, a short, light green, tubular calyx bearing five broad teeth around the edge, and five white petals. To this general pattern, male flowers add 16-20 stamens fused basally; the free ends are separated into filaments bearing tan or pink anthers. Female flowers add to the basic flower a compound style with 6-10 white, twisted, thread-like branches. The fruits are round, fist-like clusters of wedge-shaped segments (up to 10), each containing a single seed. Glade mallow occurs in only seven states. It is listed as "vulnerable" in Illinois, Iowa, Wisconsin, and Ohio; it is "imperiled" in Indiana and Minnesota and critically imperiled in Maryland. Glade mallow prefers moist habitats. Populations in Jackson Park have been noticeably expanding over the last few years; be grateful.

Napaea

Napaea dioica

glade mallow [Blooms: Jun-Aug]