Sensitive plant

Small erect or creeping herb, sometimes spreading as much as 2 or 3 feet, though usually smaller, with pinnately-compound leaves that have 10 to 26 pairs of small oval leaflets along each stemlet.
The flowers are small pink fuzzy balls about 1/2 inch in diameter, followed by clusters of 2 to 8 pods containing seeds.
The stems are purplish in color and bear small prickles.