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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]

Grape hyacinth was introduced from Europe as a garden plant. The unbranched flowering scapes are green towards the base, purplish near the flowers, reaching maximum heights of 12". The leaves are all basal, 4-10" long, 3-8 mm wide, flat, hairless, and erect. The inflorescence is a terminal raceme on the scape. Individual flowers are drooping, urn-shaped with three blue sepals and three blue petals fused along their edges nearly to their tips where there are six small, rounded lobes. There are six stamens with purple anthers and a green ovary with a single style terminating in a three-lobed stigma; all are hidden well within the mouth of the urn. The fruits are three-lobed capsules, about 5 mm long and wide.

Muscari

Muscari botryoides

grape hyacinth [Blooms: Apr]

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]

Wild daffodil is just a daffodil that has escaped cultivation — the species is native to western Europe. Wild daffodil stems get up to 20" tall; they are unbranched with a single flower at their apex. The leaves are basal, 8-20" long, about 1/2" wide, flat, and blue-green in color. The stem and flower bud are initially aligned, but the upper part of the stem becomes plastic for a short period, deforming to reorient the upper part of the stem (and the bud) to a position perpendicular to most of the stem. Each flower consists of a conical basal section (think "calyx") with six spreading, yellow lobes (equivalent to tepals). Where the lobes/tepals bend backwards, a tubular, yellow, crinkled corona perpendicular to the tepals surrounds the reproductive structures (six stamens 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 wild daffodil — if ingested, it induces severe vomiting.

Narcissus

Narcissus pseudonarcissus

wild daffodil [Blooms: Mar-May]

Evening primrose — clusters of yellow flowers occur at the apex of the plant. The flowers are 1-2" across, with four 1/2-1" long green sepals strongly reflected over a long (3/4-2"), green, cylindrical floral tube (the ovary is located just above the leaf axil), four heart-shaped yellow petals, eight stamens, and a single style with an X-shaped stigma. The sepals typically remain connected (in pairs) along one edge until the flower opens. The seedpods develop within the ovary (the base of the elongate floral tube); they are hairy, urn-shaped with rounded edges, and have four or eight small lobes on the apex. The seeds are claimed to remain viable in the soil for up to 70 years. The flowers open at dusk and close early in the day. — — — There are (at least) three evening primroses in Jackson Park — common evening primrose (Oenothera biennis), northern evening primrose (Oenothera parviflora), and hairy evening primrose (Oenothera villosa). They are easily confused with each other. (Judging by the conflicts between the accounts on Illinois Wildflowers [https://www.illinoiswildflowers.info/], Minnesota Wildflowers [https://www.minnesotawildflowers.info/], and Missouri Plants [http://www.missouriplants.com/], even the experts are confused.) All three species have yellow flowers with an X-shaped stigma, reflected sepals, petals with a small notch in their apex, stems that may be red or green, and lance-shaped leaves with short, widely-spaced teeth. Northern evening primrose is distinguished by (1) the presence of a knob or ridge at the tip of each sepal which the other two species lack (2) a seed capsule with four robust, flaring lobes with rounded tips at the apex of the seed capsule, and (3) a stigma that is very robust and almost fills the opening of the flower. Northern evening primrose has green to yellowish-green sepals. Hairy evening primrose (often but not always) has (1) striped or reddish-tinged sepals (check the buds where this character is often easier to see), (2) flowers that turn orange as they begin to senesce (although the reliability of this character is uncertain), and (3) always has glandular hairs covering the ovary that have "pimple-like" bright-red bases; these red pimples may also occur on the stems. All three species are somewhat similar to prairie sundrop (O. pilosella); the latter has very hairy stems and leaves, and translucent lines that radiate from the base of the petals in the flowers.

Oenothera

Oenothera biennis

evening primrose [Blooms: Jul-Oct]

Northern evening primrose flowers are 3/4-1.5" across, have four yellow, heart-shaped petals, eight yellow stamens, and a cross-shaped stigma on a modest style; the stamens are as long or longer than the petals and the stigma is nearly fills the floral opening. At the base of the flower are four sepals 1/2-1" long, that bend back along the 3/4-1.5" long floral tube as the flower develops with pairs of sepals attached along one edge until the flower opens. Only northern evening primrose with a distinct ridge or knob near the tips of the sepals. The seed capsule develops from the ovary; it is 3/4-1.5" long, cylindrical but tapering slightly towards the tip, with four robust, flaring lobes at the tip. — — — There are (at least) three evening primroses in Jackson Park — common evening primrose (Oenothera biennis), northern evening primrose (Oenothera parviflora), and hairy evening primrose (Oenothera villosa). They are easily confused with each other. (Judging by the conflicts between the accounts on Illinois Wildflowers [https://www.illinoiswildflowers.info/], Minnesota Wildflowers [https://www.minnesotawildflowers.info/], and Missouri Plants [http://www.missouriplants.com/], even the experts are confused.) All three species have yellow flowers with an X-shaped stigma, reflected sepals, petals with a small notch in their apex, stems that may be red or green, and lance-shaped leaves with short, widely-spaced teeth. Northern evening primrose is distinguished by (1) the presence of a knob or ridge at the tip of each sepal which the other two species lack (2) a seed capsule with four robust, flaring lobes with rounded tips at the apex of the seed capsule, and (3) a stigma that is very robust and almost fills the opening of the flower. Northern evening primrose has green to yellowish-green sepals and is the only one of the three evening primroses to (sometimes) have reddish color on some or all of the midvein of the leaves. Hairy evening primrose (often but not always) has (1) striped or reddish-tinged sepals (check the buds where this character is often easier to see), (2) flowers that turn orange as they begin to senesce (although the reliability of this character is uncertain), and (3) always has glandular hairs covering the ovary that have "pimple-like" bright-red bases; these red pimples may also occur on the stems. All three species are somewhat similar to prairie sundrop (O. pilosella); the latter has very hairy stems and leaves, and translucent lines that radiate from the base of the petals in the flowers.

Oenothera

Oenothera parviflora

northern evening primrose [Blooms: Jun-Jul]

Hairy evening primrose produves an elongating spike of flowers arises from the apex of the stem; flowers bloom near the tip while older flowers and seed capsules develop below. Individual flowers are 3/4-1.5" across; they sit on a long floral tube with the ovary at its base (attached to a leaf axil). The flowers have four yellow, heart-shaped petals, eight yellow stamens, and a cross-shaped stigma on a modest style; at the base of the flower are four sepals 3/8-3/4" long, reflected back along the floral tube as the flower develops with pairs of sepals attached along one edge until the flower opens. The sepals are often red-striped or red-tinged. Note the long, hairy floral tube below the sepals, the reddish stem, and glandular hairs with red bases on the ovary. The seed capsule develops from the ovary; it is up to 1.75" long, cylindrical but tapering slightly towards the tip, with four tiny lobes at the tip. — — — There are (at least) three evening primroses in Jackson Park — common evening primrose (Oenothera biennis), northern evening primrose (Oenothera parviflora), and hairy evening primrose (Oenothera villosa). They are easily confused with each other. (Judging by the conflicts between the accounts on Illinois Wildflowers [https://www.illinoiswildflowers.info/], Minnesota Wildflowers [https://www.minnesotawildflowers.info/], and Missouri Plants [http://www.missouriplants.com/], even the experts are confused.) All three species have yellow flowers with an X-shaped stigma, reflected sepals, petals with a small notch in their apex, stems that may be red or green, and lance-shaped leaves with short, widely-spaced teeth. Northern evening primrose is distinguished by (1) the presence of a knob or ridge at the tip of each sepal which the other two species lack (2) a seed capsule with four robust, flaring lobes with rounded tips at the apex of the seed capsule, and (3) a stigma that is very robust and almost fills the opening of the flower. Northern evening primrose has green to yellowish-green sepals. Hairy evening primrose (often but not always) has (1) striped or reddish-tinged sepals (check the buds where this character is often easier to see), (2) flowers that turn orange as they begin to senesce (although the reliability of this character is uncertain), and (3) always has glandular hairs covering the ovary that have "pimple-like" bright-red bases; these red pimples may also occur on the stems. All three species are somewhat similar to prairie sundrop (O. pilosella); the latter has very hairy stems and leaves, and translucent lines that radiate from the base of the petals in the flowers.

Oenothera

Oenothera villosa

hairy evening primrose [Blooms: Aug-Oct]

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]

Balsam ragwort flowerheads are 1/2-3/4" across 8 or 13 (rarely, 0) pale yellow ray florets and 50-65+ golden-yellow disk florets. Both disk and ray florets are perfect (i.e., have both male and female reproductive structures). The disk florets are tubular with five lobes at their apex; they have a single style and five stamens. At the base of each flowerhead is a single series of bracts (phyllaries); the phyllaries are light green, fading to pale purple at their tips. Butterweed (Packera glabella), balsam ragwort (Packera paupercula), and prairie ragwort (Packera plattensis) are easy to confuse — all boom in the late spring/early summer and all are weedy-looking plants with yellow/golden-yellow, daisy-like flowers. The flowers don't help to distinguish them; you'll need to look carefully at the leaf shape and presence/absence and quantity of wooly fine white hairs on the leaves and stems. Butterweed has large (10" long) basal leaves; the leaves are pinnatifid with multiple semicircular lobes and a circular terminal lobe. Balsam ragwort (Packera paupercula) basal leaves are no longer than 3", the flowerheads have 0, 8, or 13 ray florets, the phyllaries behind the flowerhead are purple-tipped, and wooly hairs are usually found in the leaf axils. Prairie ragwort (Packera plattensis) is extensively covered with white wooly hairs on the stems, leaves, leaf axils, and on the phyllaries behind the flowerheads.

Packera

Packera paupercula

balsam ragwort [Blooms: Apr-May]

Prairie ragworts stems and leaves are covered with cobwebby hairs and the leaf blade with felt-like hairs. Cobwebby hairs also cover the flower stems which bear a cluster of 3-12 flowerheads at their apex. Individual flowerheads are 1/2-3/4" across, with 7-12 yellow ray florets and 60-70+ orangish-yellow disk florets; both ray and disk florets have a single style and five stamens. The central disk is about 8 mm across. The fruit is a single seed suspended from a tuft of white hairs (like a dandelion). The underside of the flowerhead is covered by a single series of light green bracts (phyllaries) also covered with cobwebby hairs. Prairie ragwort can be usually distinguished from other Packera spp. by the extensive cobwebby hairs on the stems and leaves. Butterweed (Packera glabella), balsam ragwort (Packera paupercula), and prairie ragwort (Packera plattensis) are easy to confuse — all bloom in the late spring/early summer and all are weedy-looking plants with yellow/golden-yellow, daisy-like flowers. The flowers don't help to distinguish them; you'll need to look carefully at the leaf shape and presence/absence and quantity of wooly fine white hairs on the leaves and stems. Butterweed has large (10" long) basal leaves; the leaves are pinnatifid with multiple semicircular lobes and a circular terminal lobe. Balsam ragwort (Packera paupercula) basal leaves are no longer than 3", the flowerheads have 0, 8, or 13 ray florets, the phyllaries behind the flowerhead are purple-tipped, and wooly hairs are usually found in the leaf axils. Prairie ragwort (Packera plattensis) is extensively covered with white wooly hairs on the stems, leaves, leaf axils, and on the phyllaries behind the flowerheads.

Packera

Packera plattensis

prairie ragwort [Blooms: Apr-Jun]

Mature wild quinine plants are 2-3' tall. On the flowering stalks (and the side branches) are flat topped clusters of white, button-like flowerheads about 3/8" across. (The Illinois Wildflowers website considers them "similar to a head of cauliflower.") Flowerheads are composed of 15-35 disk florets, often with blackish, club-like stamens poking out; the 5-6 ray florets bear a tiny, cup-shaped petal and a pistil with a bifurcated stigma. No other wildflower in Illinois has flowerheads anything like wild quinine; common and widespread in Jackson Park.

Parthenium

Parthenium integrifolium

wild quinine [Blooms: May-Aug]

Slender beardtongue (aka, lilac penstemon) is another beardtongue/penstemon that is uncommon in Jackson Park. The stems are unbranched, green or purple, and may or may not bear hairs. There are both basal and stem leaves. The basal and lower stem leaves are 1-3" long and 1/2" wide, variable in shape and leaf margins; the stem leaves are smaller and minutely toothed. Individual flowers are pinkish, purple, or pale violet, about 3/4" long; they are comprised of a green calyx with five triangular lobes and a tubular corolla that is abruptly inflated in the more distal two thirds of the flower. The lower lip of the corolla has three lobes that extend down and out from the aperture the upper lip has two smaller, erect lobes. The interior of the corolla is white with several dark purple lines that act as nectar guides. The filament of a sterile stamen (a "staminode") bearing sparse yellow hairs runs along the midline of the lower half of the corolla, while the filaments of the other four stamens wrap around the inside of the corolla like ribs in a ribcage, with the black anthers positioned on either side of the midline of the upper corolla. A single style runs along the upper midline between the black anthers. The fruit is a more or less bullet-shaped capsule nestled in the persistant calyx. The calyx, flowers, and flower stalks are all covered with glandular hairs; the stems and leaves are not.

Penstemon

Penstemon gracilis

slender beardtongue [Blooms: Jun-Jul]

English plantain is a Eurasian exotic that is a familiar lawn weed, one with a wirelike, leafless, five-angled flower stalk 6-18" tall. At the tip of the flower stalk is a 1/2-3" long cylindrical flower spike, initially grey-green but turning brownish as the flowers open. Individual flowers have four sepals, and four petals, but their most obvious character is the long filamentous stamens with white anthers which protrude in all directions from the flower spike. The styles are white, filamentous, and fuzzy. The flowers usually open sequentially from the bottom to the top of the flower spike, first as functional females with protruding styles, then as functional males with prominent stamens; the flower spikes thus typically consist of (from top to bottom): (1) unopened buds, (2) flowers with functional styles, (3) flowers with functional stamens, (4) developing seed pods. The flowers are wind-pollinated.

Plantago

Plantago lanceolata

English plantain [Blooms: May-Aug]

Common plantain is an introduced plant commonly found in lawns and disturbed areas. The flower stalks are erect, 4-20" long; the lower third is green and unadorned while the upper two-thirds is densely covered with 1/8" green flowers. Individual flowers consist of four green sepals with a green keel and membranous margins above a single green bract, four filamentous stamens with tan to purplish anthers, a single white style, and a four small, papery, petals. The flowers are wind-pollinated. The fruits are rounded, egg-shaped capsules about 1/8" long. Common plantain is nearly indistinguishable from (the native) black-seeded plantain (Plantago rugelii); the two species differ only in the details of the sepals and seed pods. (Common plantain's seed capsule is egg-shaped and splits around the middle; black-seeded plantain's seed capsule are 2-3 times longer than wide splits nearer the bottom.) One, more ephemeral, character may help distinguish the two species in the field. According to Minnesota Wildflowers, the base of the leaf stalks of the native species (Rugel's plantain, P. rugelii) are dark red or purple in color; the base of the leaf stalks of the exotic common plantain (P. major) are uniformly green. Rugel's plantain is probably as common and tolerant of a range of habitats as common plantain, but specimens of this plant tend to be reflexively referred to "common plantain."

Plantago

Plantago major

common plantain [?-Aug]