Wild Flowers of Pittsburgh


Blue Vervain (Verbena hastata)

Verbena-hastata-2013-08-14-Schenley-Park-01The tiny flowers of this cheerful plant make a fine display—not too ostentatious, but elegant and striking. This one was growing in a field in Schenley Park, where it was blooming in the middle of August.

More pictures of this species are here, where you will also find quite a bit of lore taken from old books.

Gray describes the genus and the species:

VERBENA [Tourn.] L. VERVAIN. Calyx 5-toothed, one of the teeth often shorter than the others. Corolla tubular, often curved, salver-form; the border somewhat unequally 5-cleft. Stamens included, the upper pair occasionally without anthers. Style slender; stigma mostly 2-lobed. — Flowers sessile, in single or often panicled spikes, bracted, produced all summer. (The Latin name for any sacred herb; derivation obscure.) — The species present numerous spontaneous hybrids.

§ 1. Anthers not appendaged; flowers small, in slender spikes.

Spikes thicker or densely flowered; the fruits crowded, mostly overlapping one another; bracts inconspicuous, not exceeding the flowers; perennial.

V. hastàta L. (blue V.) Tall (0.5-2 m. high); leaves lanceolate or oblong-lanceolate, taper-pointed, cut-serrate, petioled, the lower often lobed and sometimes halberd-shaped at base; spikes linear, erect,corymbed or panicled; flowers violet-blue (rarely pink or white). —Damp grounds, etc.


Swamp Rose-Mallow (Hibiscus moscheutos)


These gorgeous flowers are the ancestors of many of our garden Hibiscus varieties. There are two main color variants: white with dark red eye (forma peckii  in older botanists) and the more common solid pink. They are not terribly common here, but locally abundant, as they were in this swamp in Cranberry, where they were blooming in late August. The USDA PLANTS database reports this species only in Allegheny and Fayette Counties in our area, but this colony was very near the line between Allegheny and Butler counties, and we are not entirely sure on which side of the border.

These pictures were taken with a cell phone while the photographer was standing knee-deep in poison ivy beside a busy four-lane highway. They are not ideal photographs, but, considering the circumstances, they are adequate. Such are the sacrifices we make to document the flora of southwestern Pennsylvania for you.

Hibiscus-moscheutos-2013-08-22-Cranberry-02Gray describes the genus and the species:

HIBÍSCUS L. Rose Mallow

Calyx involucellate at the base by a row of numerous bractlets, 5-cleft. Column of stamens long, bearing anthers for much of its length. Styles united, stigmas 5, capitate. Fruit a 5-celled loculicidal pod. Seeds several or many in each cell. — Herbs or shrubs, usually with large and showy flowers. (An old Greek and Latin name of unknown meaning.)

H. Moscheùtos L. (swamp R.) Tall perennial (1-2.6 m. high); the ■tern puberulent above; leaves ovate, pointed, toothed, the lower and sometimes the upper 3-Iobed, downy-whitened underneath, glabrous or slightly downy above: calyx and bracts densely stellate-puberulent; calyx in anthesis 2-3 cm. long, its lobes ovate or ovate-oblong; petals 6-12 cm. long, rose-color; capsule glabrous, subglobose, abruptly beaked. — River-banks and fresh or brackish marshes, near the coast, e. Mass., southw.; also lake-shores and swamps (especially near salt springs) westw. to Ont. and Mo. July-Sept.

Gray makes the crimson-eyed form a separate species, but it seems clear that in Cranberry, at least, it is the same species as the pink form:

Cut-Leaf Teasel (Dipsacus laciniatus)


Dipsacus-laciniatus-2013-08-21-Cranberry-01Very similar to the ordinary Teasel (Dipsacus fullonum), but with white flowers rather than pink ones.  In Gray’s time it was known in the North American wild only around Albany, but has since spread from New York to Pennsylvania and much of the Midwest. In Pittsburgh, it seems to be established especially along long-distance expressways, with large stands along Interstate 79 in Robinson Township and more along the Pennsylvania Turnpike; these grew in a debris-strewn vacant lot just off the Pennsylvania Turnpike in Cranberry. They may be thorny and destructive weeds, but they are favorites with bumblebees, as we see above.

Gray describes the genus and the species:

DÍPSACUS [Tourn.] L. TEASEL. Involucre many-leaved, longer than the chaffy leafy-tipped bracts among the densely capitate flowers; each flower with a 4-leaved calyx-like involucel investing the ovary and fruit (achene). Calyx-tube adherent to the ovary, the limb cup-shaped, without a pappus. Corolla nearly regular, 4-cleft. Stamens 4, inserted on the corolla. Style slender.—Stout and coarse biennials, hairy or prickly, with large ovoid-ellipsoid heads. (Name from dipsen, to thirst, probably because the united cup-shaped bases of the leaves in some species hold water. )

D. laciniatus L. Leaves pinnatifid or bipinnatifid, finely and rather conspicuously ciliate; leaves of the involucre lance-linear, spreading, usually shorter than the head. — Established at Albany, N. Y. (Peck). (Adv. from Eu.)


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