Phellodendron or Cork-tree, is a genus of deciduous trees in the family Rutaceae, native to east and northeast Asia. It has leathery, pinnate leaves, yellow clumped flowers. The name refers to the thick and corky bark of some (but not all) species in the genus.

Cultivation and uses

As an ornamental plant, Phellodendron is a tree for all seasons. In spring it has yellow flowers, in summer it provides foliage and shade, in fall the leaves turn bright yellow and the textured bark and winding branches add interest in the winter. The female bears black drupes that attract birds and other wildlife through the late fall and winter.

The Cork-tree is resistant to drought and insects, and it can thrive in a variety of soils. It is hardy to zone 4 and it is easy to maintain, sometimes to the point of being invasive. One drawback is that the drupes fall and scatter, which may be undesirable on a formal lawn.

The bark in some species is thick, resembling that of the Cork Oak, but is not thick enough for commercial cork production. It has been used to produce a yellow dye.

One species, Phellodendron amurense (Chinese: 黄柏; pinyin: huáng bǎi), is one of the 50 fundamental herbs used in traditional Chinese medicine. Recently, Phellodendron has also attracted the attention of the pharmaceutical community because of the phytochemicals it produces. Berberine has antibacterial and anti-fungal properties. Jactorrhizine may be anti-mutagenic. Phellodendrine has promise as an immune suppressant. Palmatine may be a vasodilator. The phytochemical descriptions are included for informational purposes only and not for treatment purposes. The research at this stage is very preliminary.

Sapindales