Red Oak

SCIENTIFIC NAME: Quercus rubra

FAMILY: Fagaceae

This tree in Colorado: Red Oak is native to the northeast and north central United States. It has been planted more frequently along the Front Range in the past twenty years because of its impressive fall color. It is an impressive large shade tree that does very well in many locations in Colorado largely depending on soil conditions. It prefers a well-drained sandy loam soil with a pH of less than 6.5. It will develop chlorosis in high pH soils. It is relatively pest free. Kermes scale seems to be the most common recent problem in the Denver area. Plant in full sun, allow plenty of space for growth and avoid using in heavy clay soil.

Hardiness: Zone 3

Growth habit: Large symmetrical shade tree with an initially irregular or pyramidal crown becoming broad and rounded at maturity.

Growth rate: Medium (fast for an oak), can grow 12-24” per year in the right spot. Mature size is 50-75’ in height, 50-75’ spread. State champion is 84’ tall with a 77’ crown width and 49” DBH trunk.

Foliage: Alternate, simple, with 7 to 11 broad lobes with a bristle at the tip, lustrous dark green on top, grayish or pale green underside. Fall color varies from bright red to wine red, occasionally just bronze or brown.

Flowers: Insignificant. Males produce a yellow-green catkin in the spring.

Fruit: Single or paired ¾”-1” medium brown acorns with a flat, saucer-like cap.

Bark: Distinctive wide flat gray areas with shallow fissures and ridges that deepen and darken with age.

Information sources: Michael Dirr, Manual of Woody Landscape Plants (University of Georgia, 1998)University of Connecticut Plant Database

Photo by Arbor Day blog