Xanthoceras sorbifolium (Yellowhorn), the sole species in the genus Xanthoceras, is a flowering plant in the family Sapindaceae, native to northern China in the provinces of Gansu, Hebei, Henan, Liaoning, Nei Monggol, Ningxia, Shaanxi, and Shandong.

It is a large shrub or small tree growing to 8 m tall. The leaves are arranged alternately, 12–30 cm long, and are pinnate, with 9–17 leaflets, the leaflets 3–6 cm long, with a sharly serrated margin. The flowers are 2–3 cm diameter, with five white petals, and are produced in erect panicles 10–20 cm long in mid spring. The fruit is an oval leathery capsule 5–6 cm diameter, which splits into three sections at maturity to release the 6–18 seeds; the seeds are black, 1.5 cm diameter, resembling a small Aesculus seed.

The genus considered to be the most basal member of the family.

The genus name means 'yellow horn'. The species name refers to the leaves, similar to those of rowans (Sorbus). It was originally spelled as sorbifolia, but this is a grammatical error to be corrected to sorbifolium under the ICBN.

References

1. Germplasm Resources Information Network: Xanthoceras sorbifolium
2. University of British Columbia Asian Garden Photos: Xanthoceras sorbifolium
3. Huxley, A., ed. (1992). New RHS Dictionary of Gardening. Macmillan ISBN 0-333-47494-5.
4. University of British Columbia Botany Photo of the Day, August 31, 2006: Xanthoceras sorbifolia and Aesculus hippocastanum
5. Harrington, M. G., Edwards, K. J., Johnson, S. A., Mark W. Chase, M. W., & Gadek, P. A. (2005). Phylogenetic inference in Sapindaceae sensu lato using plastid matK and rbcL DNA sequences. Systematic Botany 30 (2): 366-382. Abstract.