Pin Oak (also known as Swamp Spanish Oak or Water Oak)
Kingdom: Plantae, Division: Angiosperms, Class: Eudicots, Order: Fagales, Family: Fagaceae, Genus: Quercus, Species: Quercus palustris · Fagaceae (Beech and Oak family) · Simple, Deciduous
Species
Quercus palustris
Leaf Type
Simple, Deciduous
Family
Fagaceae (Beech and Oak family)
Shape
Pinnately lobed with deep sinuses. The lobes are U-shaped and typically end in bristle-tipped teeth.
Size
Approximately 4-6 inches long and 3-4 inches wide. This specimen appears to be a medium-sized mature leaf, within the standard range of 3-7 inches for the species.
Margin
Lobed with aristate (bristle-tipped) teeth at the ends of each lobe. The sinuses (the gaps between lobes) reach halfway or more toward the midrib.
Arrangement
Alternate
Rarity
Very Common; it is one of the most popular ornamental oaks in North American landscaping due to its fast growth and pyramidal shape.
Color & Pattern
Deep green on the upper surface with a slightly paler, duller green on the underside. In autumn, these leaves turn a distinctive bronze or russet-red before falling.
Venation Pattern
Pinnate venation with a prominent central midrib and secondary veins extending into each lobe and tip.
Texture & Surface
Upper surface is smooth (glabrous) and slightly glossy. The lower surface is mostly smooth but often features small tufts of hair (axillary tomentum) in the axils of the veins.
Description
The Pin Oak is a medium-sized deciduous tree reaching 60–70 feet. It is characterized by its unique branching habit: upper branches point up, middle branches are horizontal, and lower branches droop toward the ground. The bark is relatively smooth and gray-brown, becoming fissured with age. It produces small, rounded acorns with a thin, saucer-like cap.
Key Features
Deep, U-shaped sinuses; bristle-tipped lobes; drooping lower branches on the tree; and small acorns with thin caps.
Habitat
Found naturally in bottomlands, floodplains, and moist upland soils. It prefers acidic, poorly drained soils but is highly adaptable to urban environments.
Geographic Range
Native to the eastern and central United States, from Connecticut south to North Carolina and west to Kansas and Oklahoma. Widely planted as an ornamental tree in Europe and Australia.
Condition Notes
The leaf appears healthy with an Excellent health grade. There are no signs of oak wilt, spider mite damage, or common iron chlorosis (yellowing), which often affects Pin Oaks in alkaline soils.
Interesting Facts
The name 'Pin Oak' comes from the many small, thin dead branchlets that stick out like pins from the main trunk and branches. Historically, it was a favorite for making pins for timber-framed buildings.
Medicinal & Uses
Used primarily in landscaping and for timber (though lower quality than White Oak due to many small knots). Traditionally, Native Americans used a decoction of the bark to treat stomach aches and hemorrhages.
Ecological Role
Provides critical habitat and food for squirrels, deer, and turkeys. It is a larval host for many Lepidoptera species, including the Hairstreak butterfly.
Similar Species
Scarlet Oak (Quercus coccinea), which has deeper C-shaped sinuses, and Black Oak (Quercus velutina), which has larger, hairier buds and less deeply cut leaves.
Foraging Tips
Best identified in autumn by its persistent bronze leaves. Look for the 'pin-like' twigs on the lower trunk. The small acorns are edible after leaching out tannins, but are more bitter than White Oak acorns.
Toxicity Warning
Mildly Toxic. Like all oaks, the leaves and raw acorns contain high concentrations of tannins, which can cause gastrointestinal distress in humans and can be toxic to horses and cattle if consumed in large quantities.