Poncirus Raf. (1838), in the family Rutaceae, contains 1 species
in China. Description Shrubs to 7m, very spiny. The leaves are alternate, deciduous, aromatic, with 3–5 leaflets. The flowers are bisexual, white, in the upper leaf axils, slightly scented. Sepals 5; petals 5, thin-textured, white. Stamens 20–60. Ovary hairy, superior, with 6–8 cells, each with numerous ovules; style short. Pollination is by bees. The fruits are downy, yellow, with seeds embedded in a juicy pulp, very aromatic. Key Recognition Features The spiny, green branches, compound leaves, and white flowers. Evolution and Relationships Very close to Citrus and probably not really distinct from it. Ecology and Geography In scrub in northern China and Korea. Comment The hardiest of the citrus group, sometimes planted as an impenetrable hedge. The hybrid of Poncirus with the orange, the citrange, x Citroncirus webberi Ingram & Moore, is often planted as a hardy stock for citrus cultivars. Ponciris trifoliata Rafin. (syn. Aegle sepiaria) (Rutaceae)
Native of N. China and Korea. A spreading shrub to 3 m high, with green, spiny twigs, flowering in spring; fruits yellow, like small oranges, to 5 cm across. Only flowers freely after a warm autumn. Leaves deciduous, trifoliate. Any soil. Hardy to -15°C. |
