Calliandra Calothyrsus is a small leguminous tree or large shrub in the family Fabaceae. It is native to the tropics of Central America where its typical habitat is wet tropical forests or seasonally dry forests with a dry season of four to seven months, when it may become deciduous. It is a multipurpose legume tree that can improve the soil by fixing nitrogen from the atmosphere. It is easily grown from seed; growth is slow at first but speeds up after the first year.