Acacia, a tree or shrub found in dry tropical or subtropical areas. There are more than 800 species. Many North American acacias are known as catclaw ; several Australian species are called wattle .

Acacias vary in height from about 6 feet to 60 feet (1.8 to 18 m). Most have featherlike or fernlike leaves that are from one to four inches (2.5 to 10 cm) long. Many Australian species have flat leaf stalks, called phyllodes, rather than leaves. Acacias typically have small, yellow flowers that grow in clusters and bloom in the early spring. The fruits of acacias are brownish pods, most of which range in length from 1 1/2 to 6 inches (4 to 15 cm).

AcaciasAcacias have small yellow flowers that grow in clusters and bloom in early spring.

Acacias are grown commercially for many purposes. The blackwood acacia, or Australian blackwood, is an important lumber tree. The catechu, or black cutch, a tree native to Pakistan and Burma, yields a resinous substance used as a brown dye and in certain narcotics. Tannin, used in tanning leather, is made primarily from the powdered bark of the catechu and the golden wattle. Gum arabic, dried sap obtained from various species of acacia, is used in certain foods, paints, and inks.

Several species of acacia are cultivated for their flowers. Sweet acacia (also called huisache and cassie) bears flowers that yield an oil used in making perfumes. The flowers of the silver wattle are sold by florists under the name mimosa.

The blackwood acacia is Acacia melanoxylon; the catechu, A. catechu; the golden wattle, A. pycnantha. Gum arabic is obtained mainly from A. nilotica and A. senegal. The sweet acacia is A. farnesiana; the silver wattle, A. dealbata. Acacias belong to the pea family, Leguminosae or Fabaceae. The catclaw acacia is Acacia Greggii. The bullhorn acacia is A. cornigera.