pin oak

pin-oak的词性：
n.（名词）

1. 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.
沼生栎，椭圆果栎：生于北美东部的落叶树（沼生栎 栎属） ，有水平或垂挂枝条、全裂叶片和带碟状杯形物的小果子