| an oak, Quercus palustris, characterized by the pyramidal manner of growth of its branches and deeply pinnatifid leaves. |
| pin oak n. A deciduous tree (Quercus palustris) of eastern North America, having horizontal or drooping branches, sharply lobed leaves, and small acorns with a saucer-shaped cup. |
pin oak
either of two species of North American ornamental and timber trees belonging to the red oak group of the genus Quercus in the beech family (Fagaceae). The term is especially given to Quercus palustris, found on bottomlands and moist upland soils in the eastern and central United States. Usually about 25 m (80 feet) tall but occasionally reaching 35 m (115 feet), the tree has a broad, pyramidal crown and drooping lower branches. Spurlike, slender branchlets stand out like pins on the trunk and larger limbs. The elliptical, glossy green leaves, measuring about 13 cm (5 inches) long, have five to seven deeply cut lobes and turn scarlet in autumn. The dark brown acorns are enclosed at the base in a thin, shallow cup
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