Driving near Big Bend CA, Leonard and I noticed several California buckeyes (Aesculus californica). This shrub or small tree is a California native and is found primarily in the foothills of California. A few stands of California buckeye are also found in Southern Oregon.
Commonly called a horse chestnut, the California buckeye does resemble the horse chestnut tree I remember from my youth in Western Pennsylvania.
Averaging 10 to 15 feet in height, this buckeye has a single trunk or grows as several shrubby stems. The gray to whitish bark is smooth and in mature plants is often covered with moss or lichen.
The dark green leaves are palmate with five (usual) to seven (rare) long, pointed lanceolate lobes. The leaf edges are lightly saw-toothed. The undersides of California buckeye leaves are light green. The leaves appear in very early spring and by the heat of summer the California buckeye has “closed shop” – the leaves fall off leaving bare branches tipped with light brown or greenish fruits.
The flowers are, to my eye, beautiful and have the added bonus of being fragrant. The white, perhaps tinged with pink, flowers form 4″ to 6″ long candle like spikes (panicles) at the tips of the branches. The stamens extend far beyond the petals. The flower nectar is toxic to honeybees, so hives should not be located near California buckeyes. Yet many species of butterflies and hummingbirds drink the nectar without harm. What a paradox!
The fruit is a pear or fig-shaped pod containing one, possibly two, shiny, dark brown seeds with white meat.
When raw and untreated the nuts of this plant are quite poisonous. Several California Indian tribes used the raw nuts of California buckeye to stupefy fish so that they could be caught more easily. The nuts were also used as food. There were several ways to process the buckeye nuts to make them edible. One method consisted of roasting the nuts until they were soft then thinly slicing the meat. Placing the slices in a basket and soaking them in running water for several days would remove the poisons. I am game to try most edible wild plants, however, this long process does not seem worth the effort.
The California buckeye is often cultivated as an ornamental. Its green leaves and prolific flowers are valued in the spring. Many gardeners do not like buckeye because the branches are bare by summer and the dropping fruits can be messy. Personally I love the stark beauty of the round fruits hanging singly on the tips of bare buckeye branches.