Bur Oak

SCIENTIFIC NAME: Quercus macrocarpa

FAMILY: Fagaceae

This tree in Colorado: Bur oak is the mighty oak of the plains states. It is in the white oak group, meaning that the leaves are without bristle-tipped lobes and the fruit matures in one season. Bur oak is often thought to be native to Colorado, but Harrington's Manual of the Plants of Colorado does not include it. It is a stalwart tree for plains communities even though it grows slowly. More and more communities are planting it as a street tree. There are a few great examples of stately mature bur oaks located in Englewood, CO. These massive oaks where once seedlings planted by Sam Brown.

Hardiness: Zones 2 to 8

Growth habit: Large tree, weakly pyramidal, more oval. Grows to heights of 60' or more. If grown in the open, it has an impressive structure.

Foliage: Alternate, simple; oblong to obovate; 6" to 10" long, 3" to 5" wide; margins with 5-9 rounded lobes; dark green and glabrous above, pale and hairy below.

Fruit: An acorn nut. Short stalked. Over 1/2 is covered by a fringed cap. Matures in one season.

Bark: Thick; gray-brown; deeply furrowed and ridged.

Information sources: Michael Dirr, Manual of Woody Landscape Plants (University of Georgia, 1990)Michael Kuhns, Trees of Utah and the Intermountain West (Utah State University Press, 1998)Arthur Plotnik, The Urban Tree Book: An Uncommon Field Guide for City and Town, North Dakota Tree Handbook

Photo by onlineplantnursery.com