Quercus phellos
Willow Oak
Mature Size, Growth, Longevity
Average mature size of 40-60' tall and 30-40' wide, can reach 90-100' tall in optimal situations. National champion is over 130' tall & wide. Pyramidal in youth, dense oblong-oval to rounded crown at maturity. Medium growth rate, 1-2' per year. Long-lived, to 300-400 years.
Native Range
Kentucky Native — Found on bottomlands, floodplains and adjacent slopes, NY to FL, west to MO, OK, Texas, and into southwest Kentucky. Introduced in 1723.
Flower and Fruit Details
Flowers are monoecious. Male: pendulous yellow-brown catkins. Wind pollinated. Starts fruiting around age 20. Fruits are acorns, 1/2" long, short-stalked, with thin saucer like cap, solitary or paired. Nut is brown with vertical black lines/stripes, maturing in their second year on the tree.
Leaf and Bark Features
Deciduous: New leaves emerge yellow-bronze, turning green. Leaves are alternate, simple, lance shaped, tipped with a bristle, medium to dark green, 2-5.5" long and 1/3-1" wide, resembling those of a willow, thus the name. Finest textured oak. Petiole 1/8-1/4" long. Yellow, bronze-orange, yellow-brown, russet red to red fall color. Bark on older trunks is ridged and furrowed, gray to gray-brown in color, and finally nearly black, with thick, scaly ridges.
Culture and Care
Transplants better than most oaks because of its more fibrous root system, but should be moved during late winter/early spring. Prefers moist, well-drained soil but can adapt to nearly impossible habitats. Zones 5-9. Needs full sun; does not tolerate shade. Needs acid soil to prevent iron chlorosis. No serious disease or insect problems. Iron chlorosis may be a problem at higher pH levels.
Strengths, Weaknesses, Other Facts
Author/plantsman, Dr. Michael Dirr, calls this "the best oak for Zone 6-8 for overall texture and form; a splendid street tree… almost guaranteed to succeed and thrive." Known to withstand -25°F. Uniquely fine-textured for an oak. Good wildlife value. 3-season interest: Spring, summer, & fall. One of the most widely planted oaks in the southeast United States.
Suggested Uses
Use as a street tree, or in commercial establishments, golf courses, and parks.