Horse Chestnut or Conker Tree

Tree, up to 20 m or more. Petiole 10-15 cm long; petiolule 0.5-2 cm long. Leaflets 5-7(-9), elliptic to oblong-lanceolate, 10-20 cm long, 2.5-7 cm broad, acuminate, the middle one the largest, sub serrate, cuneate, glabrous.

Panicles 15-30 cm long, puberulous to tomentose. Calyx tube c. 5 mm long, campanulate, puberulous; lobes acute or rounded, 1.5-2 mm long. Petals 4, unequal, white, tinged yellow, 1.3-2.3 cm long, clawed, puberulous on the outside. Disc anterior, lobed. Anthers 2-2.5 mm long, oblong, sparsely pubescent; filaments about the size of the petals or longer, slightly curved, glabrous. Ovary elongated, c. 5 mm long, puberulous; style c. as long as the filaments. Capsule more or less ovoid; 3-4.5 (-5) cm long, smooth. Seeds 2.7-3.5 cm broad, dark brown, and shiny.