A common and insignificant weed, but a member of an illustrious tribe of edible leafy vegetables, and a close relative of the garden Orach (A. hortensis). The species is variable, and so is the taxonomy; in Shafer’s Preliminary List of the Vascular Flora of Allegheny County, Pennsylvania, both Atriplex hastata and A. patula are recorded; but Gray makes A. hastata a variety of A. patula, and places it chiefly in salt marshes. The family Chenopodiaceae is included by many modern botanists as a subfamily of Amaranthaceae; but the current Flora of North America at efloras.org retains it as a separate family.
Flowers. Insignificant; in greenish branching spikes, terminal and in upper leaf axils, interrupted by small leaves.
Leaves. Narrowly hastate; that is, arrowhead-shaped, with lower lobes pointed outward or forward; mid-green above, more greyish below; on short slightly winged petioles; texture somewhat rubbery.
Stem. Thin, angular; producing small branches in leaf axils; smooth; bright green.
Gray describes the genus and the species:
ÁTRIPLEX [Tourn.] L. ORACH. Flowers monoecious or dioecious; the staminate like the flowers of Chenopoidium, but sterile by the abortion of the pistil; the fertile consisting simply of a naked pistil inclosed between a pair of appressed foliaceous bracts, which are enlarged in fruit, and sometimes united. Seed vertical. Embryo coiled into a ring around the albumen. In one section, including the Garden Orach, there are some fertile flowers with a calyx, like the staminate, but without stamens, and with horizontal seeds. — Herbs (ours annuals), usually mealy or scurfy with bran-like scales and with spiked-clustered flowers; in summer and autumn. (The ancient Latin name, a corruption of the Greek, atraphaxis.)
A. pátula L. Erect or prostrate (3-12 dm. high), glabrous or somewhat scurfy; leaves narrowly lanceolate-hastate (2-10 cm. long), the lower sometimes opposite, entire or sparingly sinuate-dentate, petioled, the upper lanceolate to linear; flowers clustered in rather slender spikes, the two kinds together or separate; fruiting bracts ovate-triangular or rhombic-hastate, entire or toothed,often muricate on the back, united to near the middle. —Nfd. to N.J., Mo., and B.C. (Eu.) Very variable; the marked extremes are: Var. hastàta (L) Gray. Erect or spreading, stout, at least the lower leaves broadly triangularhastate, often coarsely and irregularly toothed. — Nfd. to Va., Mo., and northwestw., chiefly in saline places and along the Great Lakes. (Eu.) Var. littoralis (L.) Gray. Slender; leaves linear-lanceolate to linear, rarely subhastate or toothed. — P. E. I. to N. J., and westw. along the Great Lakes.
It’s easy to dismiss as just another green weed, but Pigweed is a close cousin of the cultivated amaranths, of which various varieties are grown both for their seeds (from which a flour can be made) and their beauty. If its flowers were any other color, Pigweed might join the ranks of the ornamental amaranths. Here, against a backdrop of dark green English ivy by a sidewalk in Beechview, we can appreciate the elegant architecture of Pigweed, and pause to admire it before we go back to ignoring it as usual.
Gray describes the genus and the species:
AMARANTHUS [Tourn.] L. AMARANTH
Flowers 3-bracted. Calyx glabrous. Stamens 5, rarely 2 or 3, separate; anthers 2-celled. Stigmas 2 or 3. Fruit an ovoid 1-seeded utricle, 2-3-beaked at the apex, mostly longer than the calyx, opening transversely or sometimes bursting irregularly. Embryo coiled into a ring around the albumen. Coarse annual weeds, with alternate and entire petioled setosely tipped leaves, and small green or purplish flowers in axillary or terminal spiked clusters; in late summer and autumn. (Amarantos, unfading, because the dry calyx and bracts do not wither.)
A. RETROFLEXUS L. (GREEN A., PIGWEED.) Roughish and more or less pubescent; leaves dull green, long-petioled, ovate or rhombic-ovate, undulate; the thick spikes crowded in a stiff glomerate panicle; bracts awn-pointed, rigid, exceeding the acute or obtuse sepals. Cultivated grounds, common; indigenous southwestw. (Adv. from Trop. Am.)