Quercus mongolica aka Mongolian Oak

Quercus mongolica, or Mongolian oak, is a deciduous tree. It belongs to the beech family, Fagaceae. Its home range spans temperate parts of eastern Asia. These include eastern Russia, northern China, Korea, and Japan. It also grows in eastern Mongolia and nearby islands. In its native range, it grows in forests. The tree has an upright form and an open crown.

Garden trees reach about 30–60 feet [9–18.3 metres] tall. Their spread can reach 55 feet [16.8 metres]. Oregon State reports smaller cultivated trees, around 30 feet [9 metres]. Those trees spread about 25 feet [7.6 metres]. Some trees reach 90–100 feet [27–30 metres] in height. Young shoots lack hairs. The leaves cluster near the tips of branches. Each leaf broadens toward its outer end. Coarse teeth line the edges, with small lobes at the base. The upper face is dark green; the underside is lighter. Fine hairs may grow along the veins below. Sources report both rose and brown fall leaf colors. Some brown leaves stay on the tree into winter.

Flowers appear from May to June. The same tree bears male and female flowers. Male flowers are yellow-green, while female flowers have red tones. They add little to the tree's garden display. The acorns are more striking than the flowers. Each egg-shaped nut measures about an inch long. It sits on a very short stalk. A thick cup encloses about one-third of the nut. The acorns ripen within a single year.

Full sun gives this oak its best growing conditions. It also accepts some shade, but not deep shade. Rich, moist loam with good drainage suits it best. Sandy loam also supports good growth. It can grow in other soils, including clay. It tolerates dry soil and drought. Hardiness estimates differ between the garden sources. Missouri Botanical Garden lists USDA zones 5–8. Chicago Botanic Garden lists zones 3–8. Oregon State also reports hardiness to zone 3.

This oak serves as a shade tree or street tree. It also fits woodland gardens as a canopy tree. Its broad crown and fall leaves provide landscape interest. Missouri Botanical Garden rates its upkeep needs as low. It reports no major insect or disease problems.