Spiny Amaranth (Amaranthus Spinosus)
Amaranthaceae (Pigweed family)
Group: Dicot (broadleaf)
Erect and freely branching annual herb, bearing sharp spines on the stem, native to tropical America. It is commonly found in cultivated fields, roadsides, and waste areas.
Seedling cotyledon is linear and reddish green. First leaf is spoon- or dish-shaped, hairless, borne on a long petiole. Seedling leaves are alternate, have a wavy margin and a slightly notched tip. Seedling stem is red to green stem, smooth or hairless.
Leaves of mature plants are alternate with long stalks. Leaf blades usually 1-1/2 to 4 inches long, usually egg-shaped to oval, smooth and hairless. Leaf tip somewhat pointed, often with a small bristles.
Stem is erect, branched, smooth, reddish, usually 1 to 3 feet tall, but occasionally up to 6 feet tall. Stems have a pair of 1/4 to1/2-inch long sharp spines in the axil of each leaf.
Flowers are green, in dense clusters in the leaf axils or at tips of stems. Flower clusters usually forms nods at the tip, spike width is usually 5/16-inch or more. Male and female flowers are separate, but they are mixed in the clusters. Seed covers are smooth; seeds are flattened, circular, dark brown and very small.
Root is a shallow taproot which may be or may not be red.
Propagation is by seed.