Aesculus × carnea
red horse chestnut

Sapindaceae (soapberry family)
North American
Aesculus × carnea inflorescence. John Rawlings

A cross between the common horse chestnut (A. hippocastanum) and the red buckeye (A. pavia), this tree is very striking when in bloom. The five-stemmed leaflets have rounded sawteeth.

See an example in the southeast courtyard of Wilbur Hall and four at 817 Pine Hill Road. In March 2006, the cultivar ‘Briotii’ – originating in 1858, with bright scarlet flowers – was planted at Braun Music Center, both in the courtyard facing the Post Office and on the south side, and also at Roble Gym’s south entry (removed at some later point). Two ‘Briotii’ replaced the English hollies at the entrance to the School of Education (Cubberly) in February 2008. More than a dozen red horse chestnuts grow in the parking lot on the west side of the Shopping Center, between Plum Lane and Orchard Lane.

Two beautiful specimens grew near the fence to the north of Frost Amphitheater, distinguished by the presence of both pink and yellow flowers on the same spike. One was removed around 2013, when the giant sequoia plantation was installed in that area, the other at the end of that decade.

Aesculus × carnea leaf showing 7 (rather than the more common 5) leaflets and fruit. From An Illustrated Manual of Pacific Coast Trees, Howard E. McMinn & Evelyn Maino

Name derivation: Aesculus – the Latin name for a kind of oak bearing edible acorns but applied by Linnaeus to this genus; carnea – flesh-colored. From California Plant Names.

About this Entry: The main text of this entry is from the book Trees of Stanford and Environs, by Ronald Bracewell, published 2005. (Erratum: the book’s leaf silhouette is mislabeled: leaflets of A. × carnea are sessile.) John Rawlings added the ‘Briotii’ locations ca. 2006. Family updated from Hippocastanaceae to Sapindaceae (Oct 2017, SP).