Sensitive plant is a small, spreading shrub that grows in tropical regions of the Western Hemisphere. The plant is called sensitive because its leaflets fold together when they are touched or exposed to strong fumes. At the same time, the leafstalks bend toward the main stem, as though they were shrinking from being touched.
Sensitive plants are sometimes grown in greenhouses as curiosities. Sensitive briers of the southern United States also close when handled roughly. Leaves of many members of the pea family close at night.
