Filtered (129)
A panicle of flowering stems develops at the top of a Canada goldenrod plant; the flowering stems arch away from the main stem, their upper sides covered with yellow flowers. The panicle may be pyramidal (at least as long as wide) to spreading (wider than long); it is sometimes club-shaped on smaller plants. Individual flowers are 1/8-1/4" across, with 8-14 yellow ray flowers and 3-6 yellow disc flowers. The base of the flower is surrounded by 3-4 layers of narrow, hairless, green bracts (phyllaries); the entire set of phyllaries is two to less than three millimeters long. The flower stalks (pedicels) are hairy, about as long as the set of phyllaries, and curve upwards. The fruit is a dry, ribbed seed 1-1.5 mm long with a tuft of white hairs 1.8-2.2 mm long. Canada goldenrod is difficult to differentiate from tall goldenrod (S. altissima) (both are three-nerved), but tall goldenrod has phyllaries longer than 3 mm while Canada goldenrod's phyllaries are always shorter than 3 mm. Some argue the two may be the same species but tall goldenrod blooms later than Canada goldenrod. Of the three very similar species (late goldenrod, tall goldenrod, and Canada goldenrod), only late goldenrod has a hairless stem.

Solidago

Solidago canadensis

Canada goldenrod [Blooms: Jul-Oct]

The tip of broad-leaved goldenrod's stem produces a cylindrical inflorescence (a raceme or a narrow panicle) 1.5-5" long and about a third as wide; smaller racemes (1/2-1.5" long, smaller than the leaves) arise from the axils of the upper leaves. Individual flowerheads are about 1/4" across with 3-4 yellow ray florets asymmetrically deployed around the flowerhead and 4-8 yellow disk florets. The base of the flowerhead is surrounded by 3-5 series of unequal, narrowly oblong, light green phyllaries; the outermost phyllaries are 1-2 mm long while the innermost are 3.7-4.7 mm long. Broad-leaved goldenrod prefers high-quality, moist, shaded woodlands. In Illinois, only broad-leaved goldenrod and woodland goldenrod (Solidago caesia) produce clusters of flowerheads from the axils of the middle and upper leaves. Broad-leaved goldenrod has unusually large flowers for a goldenrod and the ray florets are not evenly distributed around the flowerhead. In addition, woodland goldenrod has smooth or finely serrated leaf margins (rather than coarsely-toothed leaves) and no petioles (the leaves are sessile) — it should be easy to distinguish from broad-leaved goldenrod.

Solidago

Solidago flexicaulis

broad-leaved goldenrod [Blooms: Jul-Sep]

The central stem of late goldenrod gives rise to an inflorescence (a panicle) up to one foot long and wide made up of light green, slightly fuzzy, recurved branches with a few leafy bracts smaller than the stem leaves. Each flowerhead is about 1/4" across with 9-15 yellow ray florets and 7-12 yellow disk florets. Surrounding the base of the flowerhead are 2-5 series of appressed bracts (phyllaries) that combined are 2-4+ mm long; individual bracts are elongate lance-shaped. The flower stalks (pedicels) are minutely hairy, usually shorter than the phyllaries, all attached to one side of the panicle branches and curving upwards. Full-sized late goldenrod plants are imposing — tall, green or reddish-brown, yellow-tipped columns towering over every plant around them. The leaves of late goldenrod are similar to those of Canada goldenrod (S. canadensis), but the latter has hairy stems and tends to be somewhat shorter. Both tall goldenrod (S. altissima) and late goldenrod are three-nerved, have the largest leaves mid-stem, and pyramidal inflorescences, but tall goldenrod has rough-feeling (sandpapery) stems and leaves while late goldenrod has smooth stems and leaves. Of the three very similar species (late goldenrod, tall goldenrod, and Canada goldenrod), only late goldenrod has a hairless stem.

Solidago

Solidago gigantea

tall goldenrod [Blooms: Jul-Sep]

Early goldenrod's inflorescence is apical, a panicle of flowering stems that "often arch upward and outward like a fireworks display" (John Hilty, www.illinoiswildflowers.info). Individual flowerheads are about 1/4" across; they have 4-12 yellow ray florets, not all open at one time, and 8-15 yellow disk florets. The base of the flowerhead is surrounded by 3-4 series of overlapping, narrow, hairless, yellowish-green bracts (phyllaries) that together are 3-4 mm (1/16") long. The pedicels (flower stalks) are usually hairless, all attached on one side of the panicle's flowering branches and curving upward. The fruit is a cone-shaped dry seed 1-1.5 mm long with an attached tuft of light brown hairs 2.5-3.5 mm long. The combination of wing-like leaflets in the leaf axils, hairless stems and leaves, and an inflorescence whose flowering stems flare up and out is diagnostic for early goldenrod. Field goldenrod (Solidago nemoralis) is much the same size and general appearance, but has hairy stems and leaves, unlike early goldenrod.

Solidago

Solidago juncea

early goldenrod [Blooms: Jul/Aug-?]

The wand-shaped, nodding inflorescence of field goldenrod arises from the tip of the stem; it is 3-7" long and widest in the middle, tapering towards either end; the flowerheads are all on one side of the flower branches. Flowerheads are each 1/4" across consisting of 4-10 yellow ray florets and 3-10 yellow disk florets. The bracts (phyllaries) surrounding the base of the flowerhead are in three overlapping series; they are pale greenish yellow, covered in short, white hairs. The fruit is a dry seed 0.5-2 mm long with an attached tuft of light brown hairs. Field goldenrod can be distinguished from other goldenrods by (1) its diminutive size, (2) the inflorescence that nods to one size, (3) leaflets present in leaf axils (4) short, fine hairs on both leaves and stems, and (5) the grayish cast of the leaves.

Solidago

Solidago nemoralis

field goldenrod [Blooms: Aug-Oct]

Stiff goldenrod's inflorescence (a corymb) arises from the tip of the main stem and from the upper side stems. It is a compact, flat-topped or rounded mass of flowers 2-5" wide. Each flower is 3/8" across (big for a goldenrod) with 6-13 yellow, pistillate ray florets (with purple styles and no stamens) and up to 35 (usually fewer) yellow, perfect disc florets with five yellow stamens and a purplish, split style. The back of the flowerhead is covered with 3-5 series of overlapping bracts (phyllaries) with the midvein and other veins visible. The fruit is a dry seed that is angular in outline, about 2 mm long with a tuft of white or light brown hairs. The distinctive stiff, rounded upper leaves that clasp the stem are all you need to unequivocally identify stiff goldenrod.

Solidago

Solidago rigida

stiff goldenrod [Blooms: Aug-Oct]

Solidago sempervirens

Solidago

Solidago sempervirens

seaside goldenrod [Blooms: Sep-Oct]

Showy goldenrod's inflorescence is a showy, cylindrical panicle up to 12" long arising from the tip of the stem; the flowering stems are erect or curve upwards and the flowerheads occur on all sides of the flowering stems. (Unlike most goldenrods, where the flowering stems curve outward and downward and the flowerheads are on one side of the flowering stems.) Each flowerhead is about 1/4" across consisting of 4-10 large (for a goldenrod) pistillate ray florets (no stamens) and 6-16 perfect disk florets (both stamens and style). Behind the flowerhead are 3-4 series of overlapping bracts (phyllaries), each with a prominent midvein. The fruit is a 2 mm long seed with dark brown longitudinal grooves and a tuft of light brown hairs. Showy goldenrod is distinguished from other goldenrods by the character combination of: (1) stem leaf margins smooth (not toothed), (2) wing-like leaflets in axils of upper leaves, (3) the stems of the inflorescence erect or curve upward (not out and down), and (4) stems and leaves largely or completely hairless except in the inflorescence.

Solidago

Solidago speciosa

showy goldenrod [Blooms: Jul-Oct]

Elmleaf goldenrod's stem (and sometimes upper leaf axils) produces an open, airy inflorescence (a panicle) at its tip that may be a foot tall and wide with arching, widely-spreading branches. The flowerheads rest on very short stems (nearly sessile) along one side of the major branches, facing upward; on the opposite side of the branches are small (1") bracts. Both stems and branches in the inflorescence are covered with hairs. The flowerheads are 1/8-1/4" across with 3-6 yellow, pistillate ray florets (no stamens) and 4-7 yellow, perfect disk florets (both stamens and a style). Surrounding the base of the flowerheads are 16-18 bracts (phyllaries) in 2-3 overlapping series.

Solidago

Solidago ulmifolia

elmleaf goldenrod [Blooms: Jul-Oct]

Perennial sowthistle's upper stems produce long flower stalks at their tips. Individual flowerheads are 1-2" in diameter, composed entirely of 80-250 yellow ray florets; disc florets are absent. The fruit, popular with goldfinches, is a flat, dark brown seed with tapered ends, several longitudinal ribs, and a tuft of fine white hairs (like a dandelion). Glandular hairs are typically present on the flower bracts and stalks; if these glandular hairs are absent, glands are present in the epidermis. Perennial sowthistle is indeed a perennial, one with a taproot that may penetrate as deep as 9' into the soil. Of the local sowthistles, perennial sowthistle has by far the largest flowers; other species never exceed 3/4".

Sonchus

Sonchus arvensis

perennial sowthistle [Blooms: Jun-Oct]

Prickly sowthistle's flowerheads are dandelion-like, less than 3/4" in diameter and composed entirely of 80-250 ray florets. Glandular hairs are present on both the flowerhead bracts and on the stalks just below the flowerheads. The fruits are flattened, brown, 2-3 mm long oval seeds with 3-4 ribs per side and a tuft of white hairs on one end. Prickly sowthistle has shiny green (as opposed to the dull green of the other two species) leaves with rounded lobes (as opposed to pointed lobes of common sowthistle) at the base of the leaves. Perennial sowthistle (Sonchus arvensis) has larger (1-2" as opposed to <3/4") flowers and small, rounded lobes at the base of the leaves. The triangular lobes on the base of the leaves of common sowthistle (Sonchus oleraceus) are not found in the other two species.

Sonchus

Sonchus asper

prickly sowthistle [Blooms: Jun-Oct]

Common sowthistle flowerheads are less than 3/4" in diameter and look very dandelion-like; they open in the morning and close by noon. Each flowerhead consists of numerous (80-250) yellow ray florets; disc florets are absent.

Sonchus

Sonchus oleraceus

prickly sowthistle [Blooms: Jun-Oct]

Some upper stems produce compound umbels at their tips made of tiny, yellow flowers; the umbels are very open (they remind me of a fireworks burst), up to 4-7" across with 12-15 umbellets of about a dozen flowers. Individual flowers are about 1/8" across with five tightly furled, yellow petals; five stamens emerging from between the incurled petals and widely spreading with pale yellow anthers; and two styles. Sepals are absent. The flowers tend to be either pistillate (stamens reduced or absent) or staminate (styles reduced or absent), but a few perfect flowers occur. Yellow pimpernel prefers dry habitats on a slope at the edge of woods.

Taenidia

Taenidia integerrima

Yellow pimpernel [Blooms: May-?]

Western goat's-beard's stems terminate in a single flowerhead, with the stem strongly swollen beneath the flowerhead. Individual flowerheads are pale lemon yellow and about 2" across. Between 50-180 ray florets are present; disc florets are absent. A series of about 13 sharply pointed, narrow bluish-green bracts (significantly longer than the outer ray florets) surround the base of the flowerhead. The outer ray florets (the "petals") are much longer than the inner ray florets. All ray florets have an outer tip of the "petal" decorated with five small teeth. Near the base of the ray florets is a composite reproductive structure consisting of a single style, bifurcated at its tip, and five stamens with black anthers closely appressed to the middle of the style. The flowerheads open in the morning but close in the afternoon; the flowerheads sometimes track the sun like a sunflower. Fertilized florets produce a long, narrow, naked seed densely covered with small teeth; the seed is attached to a plume of fine white hairs (like a dandelion). The seed head looks like a giant version of a dandelion seed head. Western goat's beard is very similar to yellow goat's beard (Tragopogon pratensis) but prefers drier habitats; the latter has only eight bracts (rather than 13) surrounding the flowerhead and the bracts are the same length (not longer) than the outer ray florets.

Tragopogon

Tragopogon dubius

western goat's-beard [Blooms: May-Sep]

Yellow goat's-beard stems produce a long naked stalk from their tips that bears a single flowerhead. Individual flowerheads are bright yellow and 1-2.5" across. Between 50-180 ray florets are present; disc florets are absent. A series of about eight sharply pointed, narrow green bracts (the same length or shorter than the outer ray florets) surround the base of the flowerhead. The outer ray florets (the "petals") are much longer than the inner ray florets. All ray florets have an outer tip decorated with five small teeth. Near the base of the ray florets is a composite reproductive structure consisting of a single yellow style, bifurcated at its tip, and five stamens with black anthers closely appressed to the middle of the style. Fertilized florets produce a long, narrow naked seed; the seed is attached to a plume of fine white hairs (like a dandelion). The seed head looks like a giant (3" across) version of a dandelion seed head. Like Tragopogon dubius, it's an exotic, but at least it's less aggressive. Distinguish yellow goat's beard (T. pratensis) from western goat's beard (T. dubius) by flower color (bright yellow vs. pale yellow), foliage color (green vs. bluish green, number of floral bracts (8 vs. 13), leaf shape (tips curled vs. tips straight), and length of the floral bracts (same as petals vs. much longer than petals).

Tragopogon

Tragopogon pratensis

yellow goat's-beard [Blooms: May-Aug]

Each side stem of yellow bellwort produces a single, elongate bell-shaped flower at its tip. The flowers droop on their stem-like pedicels (about 1 " long) such that they open downwards and are often partially hidden by the leaves. Each flower is 1-2" long and consists of six yellow tepals twisted along their length (often with greenish bases), six white stamens with elongated yellow anthers, and a pistil with a three-lobed stigma. The fruit is a three-section capsule that looks (vaguely) like three fat triangles with oval bases, stuck base to base to base. Seeds are freed when the capsule splits. Seed dispersal is added by the attraction of ants to a fleshy, nutrient-rich appendage (an elaiosome) on the seed; the ants carry the seed back to their nest where they eat the elaiosome and abandon the seed.

Uvularia

Uvularia grandiflora

yellow bellwort [Blooms: Apr-May]

The apex of the common mullein plant is a club-shaped flower spike 6-24" long, covered with scattered light-yellow flowers each 3/4" across. Individual flowers have five hairy, green sepals; five pale yellow petals (the lower two slightly larger than the upper three); five stamens with reddish-orange anthers; and a single green style with a heart- or disc-shaped stigma. The upper three stamens are shorter than the other two stamens and covered with white or yellow hairs; the lower two stamens are longer and largely hairless. The fruit is an oval, two-celled seed capsule, brown when mature, each cell filled with numerous (25-150) tiny orange to brown seeds. Common mullein is immediately recognizable and impossible to confuse with any other local plant.

Verbascum

Verbascum thapsus

common mullein [Blooms: Jun-Aug]

The top of the wingstem plant is a dome (a panicle) of coarse-looking flowerheads. Each flowerhead is 1-2" across, with 2-10 yellow, oblong, drooping petals, 1/2-1" long that are derived from the sterile ray florets. Some 40-60+ yellowish-green, tubular disk florets project in all directions in a hemisphere of widely-spaced, robust, bud-like blunt cylinders, the tips of the disk florets. When receptive to pollen, the disk florets bear a protruding style with a bifurcated, curling pair of stigmas (likened by one source to a "pince-nez" — a pair of eyeglasses on a handle); the five stamens and their flattened, black anthers are appressed to the body of the style. The fruit is a teardrop-shaped seed with a pair of thin wings and two short, robust, spiky awns. Immature seeds are green; the seeds (and seedheads) turn brown when mature.

Verbesina

Verbesina alternifolia

wingstem [Blooms: Jul-Oct]