Celandine Poppy (Stylophorum diphyllum)

Like a larger version of the Celandine, this bright yellow poppy blooms at the same time, but is easily distinguished by its larger flowers with overlapping petals and bright orange stamens. This plant was blooming in early May along the Trillium Trail in Fox Chapel.

Gray describes the genus and the species:

STYLOPHORUM Nutt. CELANDINE POPPY. Sepals 2, hairy. Petals 4. Style distinct, columnar; stigma 2-4-lobed. Pods bristly, 2-4-valved to the base. Seeds conspicuously crested. — Perennial low herbs, with stems naked below and oppositely 2-leaved, or sometimes 1-3-leaved, and umbellately 1-few-flowered at the summit; the flower-buds and the pods nodding. Leaves pinnately parted or divided. Juice yellow. (From stylos, style, and pherein, to bear, one of the distinctive characters.)

S. diphyllum (Michx.) Nutt. Leaves pale beneath, smoothish, deeply pinnatifid into бог 7 oblong sinuate-lobed divisions, and the root-leaves often with a pair of small distinct leaflets; peduncles equaling the petioles; flower deep yellow (5 cm. broad); stigmas 3 or 4; pod ovoid. —Damp woods, w. Pa. to Wisc., ” Mo.,” and Tenn. May. —Foliage and flower resembling Celandine.

Star of Bethlehem (Ornithogalum umbellatum)

A European native that has made itself quite at home here, Star of Bethlehem can often be found in weedy patches of low grass. Until it blooms, its narrow leaves are hard to distinguish from the grass around them. The six-pointed white flowers are unmistakable, with six yellow-tipped stamens whose flattened “filaments” seem to form a miniature duplicate flower inside the larger one. This plant was blooming in late May beside a gas-station parking lot in Brookline.

Although most traditional references place the Star of Bethlehem in the lily family Liliaceae, modern botanists separate it into the asparagus family Asparagaceae.

Gray describes the genus and the species:

ORNITHÓGALUM [Tourn.] L. STAR OF BETHLEHEM. Perianth of 6 (white) spreading 3-7-nerved divisions. Filaments 6, flattened-awl-shaped. Style 3-sided; stigma 3-angled. Capsule roundish-angular, with few dark and roundish seeds in each cell, loculicidal. — Scape and linear channeled leaves from a coated bulb. Flowers corymbed, bracted; pedicels not jointed. (A whimsical name from ornis, a bird, and gala, milk.)

O. umbellàtum L. Scape 1-2.5 dm. high; flowers 5-8, on long and spreading pedicels; perianth-divisions green in the middle on the outside. — Escaped from gardens. (Introd. from Eu.)

Black Locust (Robinia pseudoacacia)

This tree is ubiquitous in southwestern Pennsylvania, so it may come as some surprise to Pittsburghers that we live at the northern end of a native range that is actually very small, mostly in the Appalachians and foothills. It has been much planted elsewhere, however, and may easily naturalize itself. It is in many ways an ideal urban tree: it grows fast, tolerates city conditions with no complaints, and has showy clusters of white pea flowers after most of the other flowering trees have stopped blooming. It does, however, have one serious flaw. Mature specimens are brittle, and can easily drop large branches in storms, crushing cars or bringing down power lines. When your power goes out in a thunderstorm, there’s a very good chance you have a Black Locust to blame.

The dangling chains of white pea-shaped flowers are unique among our native trees. Leaves are pinnately compound, with smooth-edged elliptical leaflets. The leaves often turn yellow and begin to drop in August, long before any other trees are even thinking about autumn. Mature trees have rough and shaggy bark, and often show scars of broken branches.

Gray describes the genus and the species (which he spells “Pseudo-Acacia”):

ROBÍNIA L. LOCUST. Calyx short, 5-toothed, slightly 2-lipped. Standard large and rounded, turned back, scarcely longer than the wings and keel. Stamens diadelphous. Pod linear, flat, several-seeded, at length 2-valved. — Trees or shrubs, often with spines for stipules. Leaves odd-pinnate, the ovate or oblong leaflets stipellate. Flowers showy, in hanging axillary racemes. (Named for John Robin, herbalist to Henry IV. of France, and his son Vespasian Robin, who first cultivated the Locust-tree in Europe.)

R. Pseùdo-Acàcia L. (common L., False Acacia.) Branches glabrous or glabrate; racemes slender, loose; flowers white, fragrant; pod smooth.— Along the mts., Pa. to Ga., and in the Ozark Mts. of Mo., Ark., and Okla.; commonly cultivated as an ornamental tree, and for its valuable timber, and naturalized in many places. May, June.