Quercus pungens aka Pungent Oak

Quercus pungens is an evergreen shrub known as sandpaper oak. It belongs to the beech family, Fagaceae. Its native range spans Texas, New Mexico, Arizona, and Mexico. It grows on dry slopes over limestone or igneous rock. These sites include oak, pinyon, and juniper woods and chaparral. It also reaches areas with desert plants. Reported shrub height is about 6.6 feet [2 metres].

The leaves stay on the plant through the year. Flowers appear from April to May on new spring growth. Each plant bears separate male and female flowers. Wind carries the pollen between them. The seeds ripen within their first year. Reports place seed length between 0.4 and 0.9 inches [1–2.2 centimetres]. This oak can cross with other oak species.

In gardens, it prefers deep, fertile loam and moist soil. It also accepts heavy clay and mildly acid to mildly alkaline soil. Grow it in sun or partial shade. Young plants can cope with shade from the sides. Woodland edges and sites with dappled shade suit its listed uses. It withstands strong winds, but not salt-laden coastal exposure. Wind may keep exposed plants small. PFAF lists USDA hardiness zones 6–9. In Britain, cool summers can leave new wood prone to winter frost damage.

Plant it in its final site while still young. Its deep taproot makes later moves hard on the plant. Sow ripe seed soon, since drying reduces its chance of sprouting. Deep pots offer one way to raise small batches. Protect sown seed from mice and squirrels. Insects may form galls, which shelter and feed their larvae. Fresh leaves used as mulch can hinder nearby plant growth.

The seeds are edible after preparation, but contain bitter tannins. Leach these out with water, then cook the seeds. Dried, ground seed can thicken stews or join flour for bread. Whole seeds may need days or weeks of leaching. PFAF lists no known hazards, but this does not establish safety for pets. The bark yields a tan dye. Galls provide tannin and dye once their insects have left. PFAF also records traditional medicinal use of the astringent galls. Leaf mulch has a reported use against slugs and grubs.