Common: Spiny Amaranth
Eastern half of the United States, especially southeastern section
This weed is an annual species that reproduces by seed and may establish itself in pastures and hayfields. It can grow to be over five feet tall with bristly looking flowers clustered along the sides and top of the plant during late summer and autumn. Stems are typically reddish. Leaves, on rather long petioles, are typically at least an inch in length but may exceed two inches. Stems may have a reddish cast. This pigweed gets its common name from the pairs of conspicuous spines (sometimes nearly a half-inch in length) at the bases of the leaves. There are many species of amaranth, and they are highly cross-reactive allergenically.