Wild Flowers of Pittsburgh


Japanese Spiraea (Spiraea japonica)

This attractive bush is a garden favorite, but it seeds itself and can become invasive. It likes a wet location, especially along the banks of a stream. This bush was growing along the Squaw Run in Fox Chapel, where it was finishing up its blooming in the middle of July.

In the horticultural trade, “Spiraea” is often spelled “Spirea.”

Gray describes the genus and the species, which in his time had not gained much of a foothold in North America:

SPIRAEA [Tourn.] L. Calyx 5-cleft, short, persistent. Petals 5, obovate, equal, Imbricated in the bud. Stamens 10-50. Pods (follicles) 5-8, not inflated, few-several-seeded. Seeds linear, with a thin or loose coat and no albumen. — Shrubs, with simple leaves, and white or rose-colored flowers in corymbs or panicles. (The Greek name, from speiran, to twist, from the twisting of the pods in some of the original species.)

Flowers In compound corymbs.

Calyx -tube top-shaped, pubescent.

S. japónica L. f. Stems 1 m. or more high; leaves 7-9 cm. long, glaucous beneath; petals pink to deep rose-color. — Frequent in cultivation, and occasionally escaping, s. Ct. (Graves) and e. Pa. (Introd. from Asia.)


White Avens (Geum canadense)

This unassuming little member of the rose family likes to grow at the edge of the woods; this plant was growing along a trail in Scott Township, where it was blooming in the early July. The white flowers bear more than a passing resemblance to the flowers of blackberries or strawberries.

Gray describes the genus and the species, which he puts in the Eugeum or Geum-proper division of the genus:


Calyx bell-shaped or flattish, deeply 5-cleft, usually with 5 small bractlets at the sinuses. Petals 5. Stamens many. Achenes numerous, heaped on a conical or cylindrical dry receptacle, the long persistent styles forming hairy or naked and straight or jointed tails. Seed erect; radicle inferior. Perennial herbs, with pinnate or lyrate leaves. (A plant name used by Pliny.)

EUGEUM T. & G.  Styles jointed and bent near the middle, the upper part deciduous and mostly hairy, the lower naked and hooked, becoming elongated; head of fruit sessile in the calyx, calyx-lobes reflexed.

Petals white or pale greenish-yellow, small, spatulate or oblong; stipules small.

Receptacle of the fruit densely hairy.

G. canadense Jacq. Stem (0.6-1.1 m. high) and petioles sparingly hairy; leaves soft-pubescent beneath or glabrate, the basal of 3-5 leaflets or undivided, those of the stern mostly 3-divided or -lobed, rather sharply toothed; stipules ovate-oblong, 1-1.5 cm. long, subentire; petals white. (G. album J. F. Gmel.) Borders of woods, etc., widely distributed.

Indian Strawberry (Duchesnea indica)

This little creeper, found in shady lawns everywhere, bears bland, tasteless fruit that looks like wild strawberries, but it’s easily distinguished by its yellow flowers. Children like to tell each other that the fruit is poisonous and then dare each other to eat it. It’s perfectly edible, but not really worth eating. It is nevertheless much valued by herbalists, who suppose it to have useful medicinal properties. These plants were growing in a lawn in Mount Lebanon, where they were blooming and fruiting in late May.

The word “Indian” in the common name of a North American plant often means “not really.” Indian Tobacco is a lobelia; Indian Bean or Indian Stogie is the Catalpa tree. So it comes as a surprise that this plant, which seems to fit perfectly into that pattern, is actually an Asian import, named not for the aboriginal Americans but for India.

Although most references place this species in the genus Duchesnea, it seems that modern genetic research (perhaps unsurprisingly) makes it a Cinquefoil in the genus Potentilla. It is not the only “Cinquefoil” with the wrong number of leaves.

Gray describes the genus Duchesnea and the species:

DUCHESNEA Sin. INDIAN STRAWBERRY. Calyx 5-parted, the lobes alternating with much larger foliaceous spreading 3-toothed appendages. Petals 5, yellow. Receptacle in fruit spongy but not juicy. Flowers otherwise as in Fragaria. Perennial herb with leafy runners and 3-foliolate leaves similar to those of the true strawberries. (Dedicated to Antoine Nicolas Duchesne, an early monographer of Fragaria.)

D. indica (Andr.) Focke. Fruit red, insipid. (Fragaria Andr.) Waste ground, grassy places, etc., s. N. Y. and e. Pa. to Fla., Ark., and Mo. (Introd. from Eurasia.)