Quercus muehlenbergii aka Chinkapin Oak

Chinkapin oak, Quercus muehlenbergii, is a deciduous tree in the white oak group of the beech family, Fagaceae. Other common names include chinquapin oak and yellow chestnut oak. It is native from southern Ontario through the central and eastern United States into northeastern Mexico. In the wild it grows on dry uplands, rocky slopes and limestone outcrops, often in alkaline soil.

This is a medium-sized tree with a broad, rounded, open crown. Most garden specimens reach 40 to 60 feet (12 to 18 m) tall. Older trees sometimes reach 80 feet (24 m). The crown often spreads wider than the tree is tall, up to about 70 feet (21 m). Growth is slow to moderate.

The bark is thin, light gray to whitish, and flaky or irregularly fissured. Together with the branch pattern, it gives the tree a pleasing outline in winter. Twigs are orange-brown with scattered pale lenticels. The simple, alternate leaves measure about 4 to 7 inches long. They are glossy green above and pale and hairy beneath, with coarse rounded or pointed teeth rather than lobes. Autumn colour ranges from yellow to brown.

Small yellow-green flowers open in spring as the leaves unfold. Male flowers hang in drooping catkins, while female flowers sit close to the leaf bases. Wind carries the pollen. The flowers have little ornamental value. Oval light brown acorns, up to about 1 inch long, ripen in a single season. A thin gray cup covers a quarter to half of each nut. A young tree may need up to 30 years before it bears its first good crop.

Chinkapin oak thrives in full sun and tolerates partial shade. It likes well-drained soil and does well in moist, fertile loam in gardens. Unlike most white oaks, it tolerates alkaline soil, with a preferred pH of about 6.5 to 8. Once established it copes well with drought. Sources list it as hardy in USDA zones 4 to 7, with some reports down to zone 3. A long taproot makes it hard to transplant, so plant it young. It suits large lawns, parks and streets as a long-lived shade tree. Gardeners rarely plant it, so nurseries may not stock it.

The tree is relatively free of pests and resists oak wilt. Oaks in general can suffer from anthracnose, cankers, leaf spots, powdery mildew and root rot. Insects that may visit include scale, borers, lace bugs, leaf miners, caterpillars and nut weevils. Damage is rarely serious. Deer browse it only lightly. Many birds and mammals eat the acorns, and the leaves feed the caterpillars of many moths and butterflies.

The acorns are sweet and low in tannin, so people can eat them cooked or roasted. Leach out any bitter ones first. Raw acorns and young leaves contain tannins and are mildly poisonous. Eating them can cause stomach pain, constipation and later bloody diarrhoea, and they can harm horses. The heavy, hard wood serves for fencing, barrels, railway ties and firewood.