Castanea

Castanea is a genus in the beech family (Fagaceae) of deciduous trees and shrubs native to temperate regions of the Northern Hemisphere. The nuts produced by many species are collected for food, and the timber is valued for its hardness and durability. The genus is closely related to oaks (Quercus) and beeches (Fagus) and is distinguished by simple, serrated leaves and spiny burrs that enclose the nuts.

Species include Castanea sativa (European chestnut), Castanea dentata (American chestnut), Castanea mollissima (Chinese chestnut), Castanea crenata (Japanese chestnut), Castanea pumila (American chinquapin). Some authorities also recognize Castanea ozarkensis (Ozark chinkapin).

Morphology: Castanea trees are typically tall, with broad crowns. Leaves are long, lanceolate, with sharp serrations. The fruit is a burr that splits to reveal one to three (often one to four) nuts with a smooth, edible kernel.

Distribution and ecology: Native to Europe, western Asia, and North America. In the United States, the American chestnut once dominated forests from Georgia to Maine; it was devastated by chestnut blight (Cryphonectria parasitica) introduced in the early 20th century, and now persists mostly in reproduced root collars and resistant hybrids.

Uses and cultivation: Nuts are eaten roasted, boiled, or ground into flour; they are highly nutritious. Wood is valued for furniture, cooperage, and tannins. Cultivation occurs in orchards and landscapes, with breeding programs aiming to restore blight resistance in C. dentata and creating hybrids with Asian species.