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Field peppergrass tems produce racemes of flowers near their apex; flowers near the top of the raceme are the youngest with older flowers (and later seed pods) further down the inflorescence. The flowers have a calyx of green or purple-green, lance-like sepals, four white, spoon-shaped petals, six stamens, and a single style. The fruits are flattened pods oval in outline with the remnants of the style protruding from a notch in the end (rather like field pennycress, Thlaspi arvense); each seedpod contains two seeds. This is an easy plant to overlook if only because it look like the weed that it is.

Lepidium

Lepidium campestre

field peppergrass [Blooms: May-?]

Peppergrass (aka, Virginia pepperweed) is a weedy, 1.5' tall, rather bushy plant. The flower spikes (racemes) are 2-4" long with tiny (<1/8") white apical flowers forming a larger inflorescence. The flowers have four oblong green or tan sepals with a white edge, half the length of the petals, alternating with four white, triangular petals. There are two stamens with yellow anthers and a stubby (0.2 mm tall) style on a green ovary. Below the flowers, the flower spike is covered with 1/8" wide seedpods on (relatively) long stalks, reminiscent of a bottlebrush; the seedpods are oval with an apical notch (much like half-sized versions of field pennycress (Thlaspi arvense) seedpods) containing two seeds. This species is native to the U.S. The stubby cylindrical inflorescences are and the triangular petals alternating with shorter sepals are diagnostic and distinguish pepper grass from field peppergrass (Lepidium campestre).

Lepidium

Lepidium virginicum

peppergrass [Blooms: Oct-Nov]

Ox-eye daisy is an aggressive plant that was introduced to the U.S. in the 19th century and is now thoroughly naturalized. Flowerheads occur singly at the apex of the stem on a long flower stalk. The flowerheads are about 1.5-2" across with 15-35 brilliant white, oblong ray florets and 120-200 yellow disc florets in a central, flattened disc about 3/4" across. The ray florets are fertile (they bear pistils with a split stigma) while the disc florets have both pistils and stamens. The disc florets are tubular with five tiny lobes at the apex, five stamens, and a single style with a bifurcated tip. The underside of the flower has numerous bracts in 2-4 layers; the bracts are green with purple to brown edges that outline each bract.

Leucanthemum

Leucanthemum vulgare

ox-eye daisy [Blooms: May-Jul]

Despite its common name, summer snowflake starts blooming in the spring (late April), not the summer. It is an introduced species, native to Europe and west Asia, similar in appearance to snowdrops (Galanthus nivalis) but larger. The leaves are exclusively basal, up to 12" long and an inch wide, flattened, arching, dark green, sheathing the base of the stems which may be the same length but are usually shorter than the leaves. The flowers dangle from the tips of hollow flower scapes in groups of 2-5, subtended by a single green, sword-shaped, spathe-like bract. Each flower has three sepals and three petals (white, pointed, with a yellowish-green spot near their tips), six stamens with orange anthers, and a single style with a green tip and a tiny stigma. Summer snowflake is toxic if ingested (like many lilies).

Leucojum

Leucojum aestivum

summer snowflake [Blooms: Apr-May]

Liriope spicata is native to east and south-east Asia but was introduced to North America (specifically Illinois and Alabama) as a ground cover — it is perennial and evergreen. A single plant grows 6-18" tall and 12-24" across; it does not tolerate foot traffic. The arching leaves are dark green, grass-like, 18" long and 1/4" across, with minutely-serrated edges and parallel venation. The inflorescence is a spike-like, brownish-white rachis covered with off white or pale lavender flowers. The flowers have six elongate oval tepals, six stamens with yellow anthers, and a stubby white style about the same length as the stamens. The fruit is a berry that is initially green, turning blackish as it matures.

Liriope

Liriope spicata

creeping lilyturf [Blooms: Aug-Sep]

American bugleweed flowers form in whorls of the axils of the middle and upper leaves. Individual flowers are 1/8" across, white with pinkish-purple spots, with a calyx about as long as floral tube with five teeth; the distal end of the short tubular corolla has five sharply-pointed, narrowly-triangular lobes. The two stamens with purple anthers and single style project well outside the mouth of the corolla. The fruits are four, flat-topped nutlets that form in the cup of the calyx. The deep, narrow lobes of the lower leaves are a characteristic of this species; they are not present in the other Lycopus species in Jackson Park.

Lycopus

Lycopus americanus

American bugleweed [Blooms: Jul-Sep]

Northern bugleweed can be up to 2.5' tall; the stem is unbranched, square in section, and light green. The leaves are opposite, 1.5-4" long and a third as wide, elliptical in outline with 5-9 coarse, sharply-pointed marginal teeth on each side of the leaf. Each pair of opposite leaves is oriented at 90° to the pairs above and below. The flowers occur in whorls in the axils of the middle and upper leaves. Individual flowers are about 1/8" long. They have a light green, very short (1 mm) calyx with 4-5 triangular teeth; a white, tubular corolla with four (or five) lobes, the uppermost notched at the tip or sometimes in two parts; two stamens with purple anthers extending just out of the corolla tube; and a style with a bifurcated tip. The fruit is four nutlets with a bumpy upper surface and a depressed center, cupped in the calyx.

Lycopus

Lycopus uniflorus

northern bugleweed [Blooms: Jul-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]

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]

Water chickweed (aka, giant chickweed) is an exotic from Europe; it resembles a much-enlarged enlarged (potentially 1-2.5' tall vs. a few inches although the stalk sprawls) version of our common chickweeds. Flowers may occur as singletons arising from the leaf axils or clusters of a few flowers at the end of the stems. Each flower is 1/2" across; it has five fuzzy, green, oval sepals slightly shorter than the petals; five white, deeply-cleft petals that look like ten; 10 stamens with white anthers; and a green ovary with five short, arching styles. The stems and the 1" long pedicels of the flowers are both very fuzzy. The fruit is an ovoid seed capsule nestled in the persistant sepals which hangs down from the pedicel when ripe; it could easily be mistaken for a bud if you didn't notice it was pointed down.

Myosoton

Myosoton aquaticum

water chickweed [Blooms: May-Jun]

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]

Poet's daffodil is an escapee from domestic gardens. The species is native to Central and Southern Europe; it is said to have been cultivated by the Greeks in the 3rd century BCE. The leaves are basal, blue-green, awl-shaped, up to 20" long and 1/2" wide, parallel-veined with smooth margins. The unbranched stems can get up to 1.5' tall, each with a solitary flower at their apex. The 2-3" diameter flowers have six white tepals with a yellow, crinkled central corona (often red-rimmed) in the form of a cup surrounding the reproductive organs (six stamens, only three of which are easily visible externally, and a single style with a three-lobed stigma). Fruits are rarely produced. The corona is relatively longer and bigger in diameter in wild daffodil than it is in poet's daffodil. Keep pets (and small children) away from poet's daffodil — if ingested, it induces severe vomiting.

Narcissus

Narcissus poeticus

poet's daffodil [Blooms: Apr-May]

Fragrant water lily flower stalks, like the leaves, develop directly from the rhizomes. Flowers are 3-6" across; they have four greenish-white sepals that rest on the water's surface; 15-40 brilliant white (occasionally pink) petals in multiple series; 35-120 stamens with bright yellow anthers distributed around the inner circumference of tthe flower; and a central stigmatic disc on the floor of the flower at the base of the stamens. Flowers open and close daily. The fruit is 1-2" long and globoid; its stalk bends downward so the fruit develops underwater. After the tiny seeds (~1/16-1/8") are released, they float for some time, dispersed by wind and water currents, then sink to the bottom of the water body where they germinate.

Nymphaea

Nymphaea odorata

fragrant water-lily [Blooms: May-Aug]

Smallflowered gaura is a spindly, usually unbranched plant that gets 2-6' fall, much of that the flower spike. The stem is round in section, light- to reddish-green, and covered with fine hairs. The leaves are alternate, 2-5" long and 1/4-1" across, lance-shaped, and sessile. The apex of the stem gives rise to a narrow spike of small flowers 1/2-2.5' long. Flowers open from the base of the spike towards the tip with relatively few open at any one time. Individual flowers are about 1/4" across. They consist of four sepals reflected back along the elongated, cylindrical, light-green or red flower stalk/ovary, four spreading white or pink petals, eight stamens, and a long style with a X-shaped (or four-lobed) stigma. The flowers are said to open in the evening and close in the morning. The seed capsules develop from the ovary; they are about 9 mm long. The flowers and flower spike of smallflowered gaura are quite distinctive and unlikely to be confused with any other species.

Oenothera

Oenothera curtiflora

smallflowered gaura [Blooms: Jul-Sep]

Star of Bethlehem's unopened flower buds bear alternating green and white triangles on the enclosing tepals that make the species easy to ID even before the flowers open. Flowers are about 3/4" across with six tepals, white on the top surface and the margins of the underside, green along the centerline of the tepal's underside; six stamens with yellow to brownish anthers whose filaments are flattened to form a visually-striking picket fence topped by sharp points; and a single pistil with a six-ridged yellow ovary and a single yellowish-green style. The fruits are three-celled with six exterior ridges, initially looking like the bottom of a miniature green bell pepper. The flowers produce lots of nectar; they tend to open before noon and close before sunset (or much earlier on cloudy days). Star of Bethlehem is an escapee from cultivation and is competitively quite aggressive. This species produces toxic cardiac glycosides throughout the plant but especially in the flowers and bulbs; it has been reported to have poisoned unwary sheep.

Ornithogalum

Ornithogalum umbellatum

star of Bethlehem [Blooms: May]

Aniseroot tends to be an understory plant, 1-2.5' tall. Individual flowers are tiny (1/8"), grouped in distinct compound umbels, each with several narrow, lance-shaped bracts with hairy margins at the base of the umbel. The flowers have a tiny green calyx without sepals, five white petals with incurled tips, five stamens with white anthers, and a pistil with a divided white style (longer than the petals — about 2 mm). The fruit is a hairy, narrow, arched seedpod about 1" long; the two styles (and, less commonly, petals and stamens) persist at the tip of the seedpod for part of the maturation. Aniseroot is very similar to sweet cecily (Osmorhiza claytonii), but aniseroot has more flowers (8-16) in each umbel than does sweet cecily (4-7) and the two styles in the flower are short and dumpy (shorter than the petals) in sweet cicely and much longer (longer than the petals) in aniseroot. The stems and stalks (except the umbel stalks) are densely covered with fine, short hairs or no hairs in aniseroot, long, spreading hairs in sweet cecily. The crushed leaflets smell like — surprise! — anise in aniseroot.

Osmorhiza

Osmorhiza longistylis

aniseroot [Blooms: Apr – Jun]