Mimosa aculeaticarpa var. biuncifera is a shrub found at all but the highest elevations in the Gila National Forest. It is armed with paired curved prickles which are numerous and effective at grabbing clothing and flesh. Mimosa aculeaticarpa is frequently found densely encircling hilltops. The flowers are in globose white clusters, and the leaves are small and pinnately compound. The branches frequently look reddish. The fruits are flattened and curved. The seeds are reddish brown, 3-4mm and ovoid.