Quassia amara

Quassia amara is a species in the genus Quassia, with some botanists treating it as the sole species in the genus. It is a shrub or rarely a small tree, growing to 3 m tall (rarely 8 m), native to Brazil. The leaves are alternate, 15-25 cm long, and pinnate with 3-5 leaflets, the leaf rachis being winged. The flowers are produced in a panicle 15-25 cm long, each flower 2.5-3.5 cm long, bright red on the outside, and white inside. The fruit is a small drupe 1-1.5 cm long. Q. amara is widely planted outside its native range.

Uses
It is famous and used for the bitterwood or quassia, its heartwood, used as a febrifuge; this contains quassin, a bitter-tasting substance (it is, in fact, the bitterest substance found in nature). Extracts of Q. amara bark containing quassinoids are used as insecticides, being particularly useful against aphids on crop plants.