Castanea sativa aka Sweet Chestnut

Castanea sativa is the sweet chestnut, also called European chestnut. This large tree belongs to the beech family. Its native range runs from the Balkans to northern Iran. It grows in mountain woods and sheds its leaves each year. People have grown it for food since ancient times. It now grows across much of Europe and nearby regions. The Romans introduced it to Britain, where it became widespread.

Sources differ on its usual height in gardens. Oregon State gives 40–60 feet [12–18 m]. Other sources give 80–100 feet [24–30.5 m]. Its spread reaches about 30–50 feet [9–15 m], sometimes more. The trunk can reach 7 feet [2.1 m] across. Young trees have upright shoots and a pointed crown. Older trees develop large, spreading lower limbs and dense shade. Deep grooves mark the dark brown bark and may spiral upward. The long, simple leaves grow in an alternate pattern. They have coarse teeth and pale green undersides. Young leaves bear hairs, while mature leaves become smooth. Their green summer colour turns yellow in autumn.

Yellow-green catkins appear from June to July on new growth. Each tree carries both male and female flowers. Bees visit the flowers, but the pollen smells unpleasant. Flowers on one tree are largely unable to fertilise themselves. At least two trees help produce fully formed nuts. Spiny husks hold glossy brown nuts and open in autumn. Birds and other wildlife feed on the nuts. People eat the seeds raw or cooked. Cooking improves their taste and gives them a floury texture. Dried seeds provide flour for bread, puddings, and soups. PFAF lists no known hazards for this species.

Grow sweet chestnut in full sun with good soil drainage. It prefers moist loam but also grows well in sand. It can grow in clay and in poor soil. Acid to neutral soil suits it best. Established trees withstand drought, and the species tolerates coastal exposure. Sources place it in USDA zones 5–7 and UK class H6. Its size makes it suited to parks and large gardens. It provides shade, edible crops, and shelter for wildlife. Fallen nuts create litter and can increase upkeep.

Chestnut blight is a serious threat to this tree. Leaf spot, anthracnose, and powdery mildew can also occur. RHS also lists phytophthora and honey fungus as risks. It reports few pest problems. The durable wood serves for furniture, barrels, fences, and beams. It can split or warp. The bark and other parts supply tannins. PFAF records traditional medicinal uses of the leaves and bark.