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Common boneset's upper stem and branches bear clusters 2-8" across of white flowerheads. Each flowerhead is about 4-6 mm across consisting of ~15-20 dull white disk florets (ray florets are absent); florets have a tubular corolla with five triangular lobes at the apical end and a long, bifurcated style surrounded at its base with a brown column of five stamens with purplish anthers. Ironically, "common" boneset is less common than late boneset or tall boneset in Jackson Park.

Eupatorium

Eupatorium perfoliatum

common boneset [Blooms: Jul-Aug]

Late boneset's inflorescence is a flat-topped or shallowly-domed panicle with numerous flowerheads. Individual flowerheads are composed of 12-15 greyish-white disk floret (ray florets are absent) about 1/4" long with a tubular corolla with five small, triangular apical lobes and a long white bifurcated style extending well out from the floret surrounded by five black stamens. Leaf venation, lack of leaf hairs, and and smaller flowerheads (~5-8 florets) distinguish tall bonset (E.altissium) from late boneset (E. serotinum; 12-15 florets).

Eupatorium

Eupatorium serotinum

late boneset [Blooms: Aug-Oct]

Flowering spurge "flowers" are deployed in an open, flat-topped inflorescence (panicle); individual "flowers" are 1/4-3/8" across, a cup-like, five-lobed cyathium (unique to euphorbs) containing the five white "petals" (actually white bracts), a green ring of nectar glands around the base of the "petals," and the stamens or styles. Male flowering spurge cyathia have three stamens, each with a white filament and a yellow anther; female flowering spurge cyathia have both an ovary with a tripartite style with six stigmas, and three (sterile?) stamens. (If you're confused about the architecture of cyathia, see seaside sandmat (Euphorbia polygonifolia) for a clearer example.) After fertilization, the fruit develops as a unmistakable three-celled, bulbous green capsule on a short stalk in the middle of the original flower with the remnants of the style at its tip.

Euphorbia

Euphorbia corollata

flowering spurge [Blooms: Jun-Oct]

Seaside sandmat cyathia (cup-like reproductive structures typical of euphorbs) develop between pairs of leaves, typically one cyathium with a short reddish stalk per pair of leaves. On the rim of the cyathium are four to six red nectar glands; each nectar gland alternates with a narrow, elongate lobe. In the center of the cyathium is a female flower with a three-lobed, light green ovary topped by a tripartite style; the flower sits on a stout pedicel that elongates and curves as it matures. Between the central female flower and the rim of the cyathium are several male flowers, each consisting of a single stamen. Seaside sandmat prefers beach habitats around the Great Lakes and along the Atlantic coast.

Euphorbia

Euphorbia polygonifolia

seaside sandmat [Blooms: Jul-Sep]

Lance-leafed goldenrod is only distantly related to the other goldenrods (all genus Solidago) found in Jackson Park. The inflorescence is a flat-topped or slightly domed panicle. Flowerheads are cylindrical, minute (1/8" across, the smallest of the goldenrods), with 15-25 ray florets with minute petals and 5-10 disc florets. The outermost bracts around the base of the flower are green-tipped. Flowers across the inflorescence bloom at different times so the inflorescence often looks a bit shopworn. Lance-leafed goldenrod refers wet, soggy habitats.

Euthamia

Euthamia graminifolia

lance-leafed goldenrod [Blooms: Jul-Sep]

Spotted Joe-Pye weed flowerheads are pink to pinkish-purple, about 8 mm long, consisting of 8-20 disk florets, each with a tubular corolla with five tiny spreading lobes at its apex, five stamens with white anthers, and two long, thin white styles that extend well outside the floret; there are no ray florets. The flowers make either a rather flat or domed cluster (panicle) at the apex of the plant. The bracts (phyllaries) around the base of the flower are purple-tinged or the same color as the disc florets. Spotted Joe Pye weed (E. maculatum) has purple or purple-spotted, hairy stems and flowers with 8-20 disc florets; sweet Joe Pye weed (E. purpureum) has green, hairless stems with purple color only at the leaf nodes and flowers with 4-7 disc florets.

Eutrochium

Eutrochium maculatum

spotted Joe-Pye weed [Blooms: Jun-Sep]

Sweet Joe-Pye weed's inflorescence is a domed or pyramidal panicle. The flowerheads are whitish-pink to pinkish-purple and strikingly variable in color between plants, 1/4-3/8" long, consisting of 4-7 disk florets, each with a whitish-pink to purplish-pink tubular corolla with five lobes at its apex, two long, thin white styles extending well outside the floret and five stamens fused to the corolla about halfway up its length; there are no ray florets. The flowerheads make a domed (rather than flat) cluster at the apex of the plant. The bracts (phyllaries) around the base of the flowerhead are pale pink.

Eutrochium

Eutrochium purpureum

sweet Joe-Pye weed [Blooms: Jul-Aug]

Black bindweed flowers develop in singletons or pairs from the leaf axils or directly from the stem. Flowers are 1/8-1/4" long; they have 3-5 greenish-white, white, or light purple petal-like tepals, the outer three tepals with a ridge or keel down the midline on the outer surface. Six to eight stamens with purple anthers surround fused green styles with a dome-shaped stigma in the middle of the flower; the flower usually opens only partially (like a tulip). The fruit is three-sided, with a tubercle-covered surface, about 1/4" long, black when fully mature. Black bindweed is very similar to climbing false buckwheat (Fallopia scandens).

Fallopia

Fallopia convolvulus

black bindweed [Blooms: Jun-Jul]

Climbing false-buckwheat stems are round, angular, or ridged in section, often with hairs on the ridges. Racemes of flowers arise from the leaf axils; the flower stalks are usually vertical, 3-8" long and bear both erect flowers and drooping fruits. Individual flowers are greenish-white, about 3/16" across have eight stamens with white anthers and an ovary bearing a tripartite style; the thee outermost tepals (petals) have obvious wings, unsually with an undulating margin; the inner two tepals are simple ovals. The fruit (~3/8" long) has a greenish center with three white wings; the 3 outer tepals with enlarged wings enclose the seed. (The fruit resembles a much-enlarged version of the fruit of curly dock (Rumex crispus).) Climbing false-buckwheat is very similar to black bindweed (Fallopia convolvulus) but is far more common in Jackson Park.

Fallopia

Fallopia scandens

climbing false-buckwheat [Blooms: Aug-Sep]

Queen-of-the-prairie produces over 100 flowers (1/3" wide) in the panicle with five triangular, purplish sepals, five rounded pink petals with narrow bases, 15+ long white stamens with pink anthers, and a ring of 5-15 curved styles with large, disk-like, white stigma. The fruits are striaght or slightly curved stout banana-like spindles 1/4-1/2" in diamater on a narrow stalk.The numerous pink flowers with their long protruding stamens tipped with pink anthers gives the inflorescence the air of pink clouds, or possibly cotton candy. Rare, but unmistakeable if you spot it. Critically imperiled in Illinois (and elsewhere in the Midwest).

Filipendula

Filipendula rubra

queen-of-the-prairie [Blooms: Jul-Aug]

Forsythia flowers occur singly or in clusters of 2-3 arising from the axils of leaf buds; the flowers have short (1/8-1/4") pedicels. The flowers consist of four green 1/4" long sepals fused at their bases; a bell to saucer-shaped corolla that also has four deep, strap-shaped, brilliant yellow lobes; two stamens that are fused to the base of the corolla tube; and a single style with a pair of ascending, hemispherical terminal lobes (the stigmas). Forsythia is distylous, producing either short (3-5 mm) stamens in combination with long (5-7 mm) pistils or long (6-7 mm) stamens in combination with short (3 mm) pistils. Each of these flower morphs is restricted to a given plant; forsythia is an obligate outcrossing species. Fruits are rarely produced in North American forsythia, possibly because the complementary flower morph is rarely in close proximity to a given plant. However, forsythia can propagate asexually via cuttings.

Forsythia

Forsythia suspensa

forsythia [Blooms: Mar-Apr]

Wild strawberry always show a terminal marginal tooth of each leaflet that is shorter (and often narrower) than the teeth on either side, a diagnostic character. Clusters of white flowers are borne on 5" long, hairy peduncles. Individual flowers are on 3/4" long (again hairy) pedicels. The flowers are 1/2-3/4" across; there are five green, narrow, pointed, hairy sepal-like bracts; five hairy, lance-shaped sepals; five oval white petals longer than either the bracts or the sepals; and variable reproductive organs depending on whether the flower is male (least common, with ~20 yellow stamens and anthers), female (with a central yellow dome of pistils), or "perfect" (both male and female, with the appropriate organs). Fruits are familiar, if small (1/2") strawberries, bright red when ripe, with the seeds sequestered in sunken pits so the surface is mostly smooth; the fruit hangs beneath - and is tightly embraced by - the sepals and sepal-like bracts, is edible, and is tasty, if a bit tart. Wild strawberry superficially resembles mock (Indian) strawberry in its foliage and (superficially) fruit, but wild strawberry has white flowers, not yellow; the fruit of wid strawberry hangs below the sepals rather than resting above the sepals as in mock strawberry; and the seeds of wild strawberry lie embedded in the surface of the fruit rather than protruding as in mock strawberry.

Fragaria

Fragaria virginiana

wild strawberry [Blooms: Apr-May]

Green ash is dioecius; each tree produces only either male (staminate) or female (pistillate) flowers (which are wind pollinated). The flowers open in mid-spring, before the leaves emerge. Male flowers are produced in compact clusters that envelop short sections of the second-year twigs. Each staminate flower is yellowish green to greenish purple and less than 1/8" (3 mm) across, consisting of a tiny, four-lobed, tubular calyx and a pair of purplish stamens. Petals are absent. Female flowers are also produced on the second-year twigs, in this case in small panicles. Each female flower consists of a tiny four-lobed, tubular calyx and a pistil with a single, long style; again, petals are absent. Fertilized flowers are replaced by panicles of drooping, spatula-shaped, winged seeds 1-2.5" long and 1/4-1/3" wide that have an ellipsoid swelling at one end containing the seed and a single elongated, membranous wing with a rounded or notched tip. When released in the autumn, the greenish to tan fruits spin around the seed, reducing their rate of fall so they can be carried greater distances by the ambient wind. Green ash is tolerant of shading so can grow in mature forests; it prefers moist soils and can tolerate some flooding.

Fraxinus

Fraxinus pennsylvanica

green ash [Blooms: May?]

Indian blanket flowers are 1-2.5" across with 6-15 sterile ray florets; the petals are 3/4-1.25" long, red or brownish-red with yellow tips; the base of the petal is narrow and the tips of the petals are divided into three sharp or rounded teeth or lobes. Disc florets are brown, numerous (40-100+), with tubular corollas that may be orangish, red, brownish-red, or purple with five tringular, hairy lobes at the apex; the flowers are perfect with both stamens and styles.

Gaillardia

Gaillardia pulchella

Indian blanket [Blooms: Jul-Oct]

The white, waxy, drooping flowers of greater snowdrop are born on leafless scapes (flower stems). The flowers consist of three white outer tepals and three white inner tepals; the outer tepals have distinctly narrowed bases while the inner tepals are more rectangular, usually with a green blotch at their base and tip or a bold green stripe running from base to tip. (Common snowdrop flowers have a single, restricted blotch of green on their inner tepals.) There are six stamens with yellow anthers recessed inside the edge of the inner tepals; the stamens form a ring around the style. The style is slender, cylindrical, and slightly longer than the stamens. The fruit is a spherical to ellipsoid green capsule that splits into thirds when ripe, releasing the seeds.

Galanthus

Galanthus elwesii

greater snowdrop [Blooms: Mar-Apr]

Snowdrop is the earliest blooming flower in Jackson Park (late February); individual blooms can persist for about a month. The bell-shaped flowers hang down on a thin peduncle from a smooth, hairless flower stalk up to 10" long. The flowers have six oval, half-spread tepals; the three outer tepals are white with rounded tips, the three inner tepals are white with green, notched tips and green stripes on the interior surface. There are six stamens with yellow-orange anthers and a single greenish-white style. The fruit is a green, egg-shaped enlarged ovary with a flattened distal tip that dangles form the peduncle. Snowdrops usually exist in a given spot because of a prior deliberate cultivation (in some recorded cases, up to 60 years earlier) and rarely pose an invasion threat; they typically propagate from bulbs. The source of the snowdrops in Jackson Park is unknown.

Galanthus

Galanthus nivalis

snowdrop [Blooms: Feb-Mar]

Gallant-soldier (aka, small-flowered galinsoga) flowerheads are about 1/4" across; they have 4-8 (usually 5) ray florets with a single minute (about 2x2 mm) white petal notched to produce two or three lobes; the ray florets are distributed around the circumstance of the disc. There are 15-50 golden yellow, tubular disc florets with five short triangular lobes at their apex. Both ray and disc florets are fertile; the ray florets are pistillate while the disc florets are perfect (both pistils and stamens). The fruit (a cypsela) consists of a black, conical seed suspended beneath about five off-white, papery, fringed scales that act as a parachute. Gallant-soldier is very similar to galinsoga (Galinsoga quadriradiata); the latter has larger flowerheads and ray floret petals.

Galinsoga

Galinsoga parviflora

gallant-soldier [Blooms: Aug-Sep]

Galinsoga (aka, Peruvian daisy or shaggy soldier) flowerheads are small (1/4" across) with 4-8 (usually five) widely separated 2.5 mm long, white ray florets with three teeth at their tips. The 15-35 disc florets are yellow. Both ray and disc florets are fertile; the ray florets are pistillate while the disc florets are perfect (both pistils and stamens). The fruit (a cypsela) consists of a black, conical seed suspended beneath about five off-white, papery, fringed scales that act as a parachute. A poisonous plant (Tridax procumbens) with nearly identical flowers (but distinctly different leaves) is (luckily) restricted to FL and TX in the U.S. so not likely to show up in Jackson Park. The name Galinsoga ciliata, sometimes still used for Galinsoga quadriradiata, is invalid (ITIS); according to the USDA Plants database, C. ciliata has been superceded by either G. quadriradiata or G. urticifolia.

Galinsoga

Galinsoga quadriradiata

galinsoga [Blooms: Jun-Oct]