The pin oak (Quercus palustris) is a small- to medium-sized tree with a characteristic branching pattern: upper branches project upward, middle branches project straight out and lower branches project downward. The tree is deciduous and the leaves grow alternately on the twigs. The leaves are deeply and widely lobed; the underside of the leaf is lighter with hairs along the mid-vein. The autumn leaf is bright red. The flowers are male and female catkins. The fruit is an acorn with a shallow tightly scaled cup. The tree is native to the eastern part of North America and is perhaps the most popular commercial oak, having been widely planted as both a street and landscape tree. Characteristics: Pin oak is a hardy wind firm oak planted as a street tree for its bright red autumn foliage and handsome shape. It is common in New Jersey, Delaware and along the lower Ohio River. Pin oak’s drooping lower branches are reminiscent of those of Scarlet and Jack Oaks. The “pins” in the common name are the short, sharp spur shoots, especially common on young shoots, and seen best in winter when the leaves are off. Pin oak arrived in Britain in 1800. Like all Fagales many leaves are retained during the winter. The Latin name for acorn is ‘glans’ which is morphologicall similar to the tip of the mammalian penis also called a ‘glans’. Quercus is the Latin name for “oak”.
Common name: Pin Oak, Swamp Oak, Water Oak, Spanish Oak
Scientific Name (family and order): Quercus palustris Munchhausen (Fagaceae, Fagales)
Species Origin: S.E. Canada, E. United States.
New Jersey Status: USDA Native
Habit: 50 -100’ high x 1 -2 diameter; relatively narrow upright habit; broadly conical crown of upturned upper branches and spreading side branches; pendulous. Retained lower branches can form a “skirt” around the lower trunk.
Habitat: Zones 4 -8; swampy woods. Few oaks can withstand flooding and wet ground as well as this species.
Trunk/Stem: Bark dark gray, smooth and eventually developing ridges and furrows. Persistent small branchlets common along trunk and branches.
Leaves: Deciduous, Simple, Alternate. Elliptical to obovate in shape; 3 – 6” long x 4 ¾ “ wide; deeply lobed, glossy green on both sides but tufts of hair on veins beneath. Three to four lobes per side with deep sinuses – nearly to the mid-vein – and each lobe tipped by sharp bristle.
Flowers: Monoecious. Flowers appear on old or new growth; staminate catkins pendent and clustered; its flowers comprise a 4 – 7 lobed calyx which encloses 6 stamens. The pistillate flowers are solitary or on few-to-many-flowered spikes which form in the axial of new leaves. Individual flowers consist of a 6 lobed calyx surrounding 3-celled ovary; the whole is partly covered by the involucre.
Fruits and seeds: Fruit an acorn, 5/8” long; ¼ of the nut enclosed in the cup. The cup scales are tightly packed. Acorn borne singly or in clusters.