Quercus chrysolepis

canyon live oak


The Basics

Taxonomy: Kingdom - Plantae (plants). Subkingdom - Tracheobionta (vascular plants). Superdivision - Spermatophyta (seed plants). Division - Magnoliophyta (flowering plants). Class - Magnoliopsida (dicotyledons). Subclass - Hamamelididae.
Order - Fagales. Family - Fagaceae (beech) Genus - Quercus L. (oak). Species - Quercus chrysolepis Liebm. (canyon live oak).

Ecology: Canyon live oak is one of the most morphologically variable oaks in North America. It is a spreading, perennial, sclerophyllous evergreen that ranges from less than 5-30 m tall and up to 3.3 m DBH. Its growth form varies depending on the site. It grows as a shrub and may form dense thickets on mountain slopes and ridgetops, and it grows as a tree in sheltered, moist canyons. Its size generally increases with soil depth. In open areas the crown is dense, wide-spreading, and reaches nearly to the ground... Canyon live oak is a thin-barked tree for its size. The bark is smooth to flaky. Canyon live oak has a deep and extensive root system. Road cuts have exposed roots up to 7.3 m deep.


A wide-spreading, evergreen oak, seldom more than 60 ft. in height and often no more than a tallish shrub in dry sites. Branchlets are often pendulous. Oval leaves are toothed or smooth (sometimes both on the same tree), not lobed, and felty-white beneath. Foliage color varies from blue-green to glossy, dark-green. Evergreen tree with short trunk, large, spreading, horizontal branches, and broad, rounded crown; sometimes shrubby. Many consider this to be the most beautiful of the California oaks. The species name, meaning golden-scale, refers to the yellowish acorn cups.


Canyon live oak is less susceptible to the oak wilt pathogen Ceratocystis fagacearum than the deciduous red or black oaks (subgenus Erythrobalanus) in California. In an inoculation experiment, canyon live oak was the least susceptible to oak wilt out of 7 species tested. Where canyon live oak grows in association with California black oak, however, it may be more susceptible to oak wilt. Canyon live oak is a host of Phytophthora ramorum, the pathogen that causes sudden oak death disease in tanoak and many species of oak (Quercus spp.) in California and Oregon.

Fire effects: Although canyon live oak is easily top-killed by fires of even relatively low severity, the entire tree is rarely killed. Small canyon live oak trees and shrubs are more vulnerable to fire than large trees. Even relatively large canyon live oak trees, however, have thin, flaky outer bark that is easily ignited. The bark can ignite even during a low-severity surface fire, carrying fire up the trunk and into the crown. Trees can experience fatal cambium damage when the trunk and/or crown is burned. Leaves may be heat-killed even if they do not burn. Mortality may also result from root crown damage caused by smoldering leaf litter at the base of trees. Canyon live oak acorns are generally destroyed by fire. Fire triggers a strong sprouting response in canyon live oak...Canyon live oak regenerates by sprouting from the root crown or bole after it is damaged or top-killed by fire. Canyon live oak can sprout within weeks after a fire, advancing regeneration and helping to maintain canyon live oak cover. Repeated burning favors the shrubby growth form of canyon live oak.


Seed Production - Canyon live oak is wind pollinated and monoecious...The minimum seed-bearing age in canyon live oak is 20 years. Canyon live oak is a "prolific" seed producer at irregular intervals.

Seed Dispersal - Canyon live oak acorns are large and usually fall a short distance from the tree. On steep canyon slopes, acorns may roll downhill a long distance. Small mammals and birds that cache canyon live oak acorns are also effective dispersal agents.

Seedling Establishment - Seedling growth is relatively slow in canyon live oak. Seedlings grow best in shade.

Vegetative Regeneration - Canyon live oak sprouts from the bole or root crown after fire or other disturbances. In recently disturbed stands, sprouting results in a high density of small-diameter (2.8-35 cm) canyon live oak stems. Seedlings may sprout following top-killing disturbance.

Species Distribution


USDA Plant Database
USDA, NRCS. 2016. The PLANTS Database (http://plants.usda.gov, 4 February 2016). National Plant Data Team, Greensboro, NC 27401-4901 USA.

Flora of North America
Flora of North America Editorial Committee, eds.  1993+.  Flora of North America North of Mexico.  19+ vols.  New York and Oxford.

Silvics of North America
Burns, R.M., and B.H. Honkala. 1990. Silvics of North America (Volume 2: Hardwoods). USDA Forest Service Agricultural Handbook 654.

Intermountain Herbarium
Consortium of Intermountain Herbaria. 2016. http//:intermountainbiota.org/portal/index.php. Accessed on February 04.

Jepson Manual
The Jepson Manual: Vascular Plants of California. B.G. Baldwin, D.H. Goldman, D.J. Keil, R. Patterson, T.J. Rosatti, and D.H. Wilken [editors]. 2012. 2nd edition, thoroughly revised and expanded. University of California Press, Berkeley, CA. $131.95, hardcover; 1600 pages. ISBN-13: 978-0520253124.

USGS Plant Species Range Maps
Critchfield, W.B., and Little, E.L., Jr., 1966, Geographic distribution of the pines of the world: U.S. Department of Agriculture Miscellaneous Publication 991, p. 1-97.
Little, E.L., Jr., 1971-1978, Atlas of United States trees, volume 1,3,13,17, conifers and important hardwoods: U.S. Department of Agriculture Miscellaneous Publications.