staff tree, common name for some temperate members of the Celastraceae, a family of trees and shrubs (many of them climbing forms), widely distributed except in polar regions. These plants typically bear small greenish flowers and have seeds with brightly colored (often orange or scarlet) coats that are exposed when the mature seed pod splits open. Their fruit and brilliant autumn foliage make many species popular as ornamentals. The spindle trees (genus Euonymus ) include the wahoo, or burning bush ( E. alatus, E. atropurpureas ), and the strawberry bush ( E. americanus ), both of E North America, and a Western species ( E. occidentalis ) that is also sometimes called wahoo. The East African plant Catha edulis is the source of khat or qat, a popular Yemeni and East African tealike beverage or masticatory made using the leaves. Khat contains cathinone, a stimulant that is similar chemically to amphetamine, and is illegal in the United States. Several members of the family are valued for their medicinal bark as well as for decoration, e.g., the wahoo and the staff trees of the genus Celastrus and the Amazonian chuchuhuasi or chichuá of the genus maytenus. ( C. scandens is the climbing bittersweet of North America.) Staff trees are classified in the division Magnoliophyta, class Magnoliopsida, order Celastrales, family Celastraceae.