Vegetative plants. Key characteristics: leaves have relatively long petioles and appear to be symmetrically arranged. Often, a watermark will be present on the upper leaf surface.
Flowering structures. Male and female flowers are on separate plants. The stalks are primarily non-branched and may reach a length of two feet. The female flowers feel spiny to the touch.
Seed. Seed are round and flattened with a dark glossy shine. The diameter is slightly less than 1.0 mm.
Life cycle: summer annual.
Toxic Plant: Cattle and swine are the animals most likely to be affected; goats and sheep can also be poisoned. Leaves, stems and roots are toxic. The most common symptom in cattle is bloat as it accumulates nitrates.