Chrysolepis sempervirens

Bush chinquapin


The Basics

Taxonomy: Kingdom - Plantae (plants). Subkingdom - Tracheobionta (vascular plants). Superdivision - Spermatophyta (seed plants). Division - Magnoliophyta (flowering plants). Class - Magnoliopsida. Subclass - Hamamelididae. Order - Fagales. Family - Fagaceae (beech). Genus - Chrysolepis Hjelmquist. Species - Chrysolepis sempervirens (Kellogg) Hjelmquist

Ecology: Bush chinquapin often dominates or codominates the understories of mid-seral coniferous forests adjacent to montane chaparral. Coniferous forests may also contain scattered thickets of bush chinquapin on sites unfavorable to conifer growth, such as rocky outcrops or dry ridges. Bush chinquapin occupies breaks in the overhead canopy where windthrow or tree death has occurred. Montane chaparral is seral to various coniferous forests. Bush chinquapin is an enhanced survivor in these early- to mid-seral communities. Its cover is greatest in the late mid-seral stage, when tree canopy begins to close. Bush chinquapin is moderately shade tolerant and grows in the lower strata of near-climax open coniferous forests. When fire is excluded from coniferous forests for long periods of time, bush chinquapin is shaded out. Montane chaparral represents a topographic or edaphic climax on some sites, such as steep, south-facing slopes or areas with shallow rocky soil. Bush chinquapin is considered part of climax vegetation on such sites.

Bush chinquapin is a common codominant of montane chaparral. Occurring at higher elevations than other types of chaparral, montane chaparral consists of low-growing, often dense thickets of sclerophyllous shrubs in the coniferous forest zone. Forest cover is lacking, usually due to removal of trees by fire or logging. Mountain whitethorn (Ceanothus cordulatus), snowbrush ceanothus (Ceanothus viscidiflorus), and greenleaf manzanita (Arctostaphylos patula) are frequent codominants. Together these shrubs may form almost impenetrable stands. Bush chinquapin also occurs in pure stands. These are not extensive in montane chaparral but are common in alpine zones. Bush chinquapin hybridizes with giant chinquapin (C. chrysophylla) in western Siskiyou County, where distributions of the two species overlap.


Shrubs , rhizomatous-spreading, 0.2-1(-2.5) m. Bark gray or brown, thin, smooth. Twigs densely covered with tight, yellowish, peltate trichomes. Leaves: petiole 10-15 mm. Leaf blade oblong to oblanceolate, to 75 mm, margins entire, apex obtuse, occasionally somewhat acute; surfaces abaxially rusty or golden pubescent, often becoming glabrate and glaucous with age. Fruits: cupule yellowish, 20-60 mm thick, densely spiny, surface obscured; nut light brown, 8-13 mm, glabrous, completely enclosed by cupule until maturity. (Plant Database)


Fire effects: Fire top-kills bush chinquapin. Bush chinquapin survives fire by sprouting from the roots, root crown, and stump when aboveground portions of the plant have burned. Because bush chinquapin occurs in many plant communities, natural fire regimes vary. Thickets growing in rock outcrops escape fire for long periods of time. Plants in the understory of coniferous forests historically burned often. Mixed coniferous, sequoia, ponderosa pine (Pinus ponderosa), and Jeffrey pine forests burned at 2- to 8-year intervals prior to fire suppression. Frequent fire in these forests favors understories of bush chinquapin over understories of coniferous seedlings.


Seed production - Male catkins are produced from the tips of terminal and side branches. One to three female flowers grow at the base of the male catkins or on short separate catkins. The fruit is a nut with a woody seed coat enveloped by a densely burred involucre. Nuts contain from one to three seeds, usually one. Plants flower continuously from July through September in most of their range. Seed ripens in the late summer or early fall of the second year of development. Nuts open in mid-fall. Chinquapins are wind pollinated. Most seed falls under the parent. Some seed may be disseminated by animals when the nut burs catch on furs or hides. Other seed is dissemminated by seed-eating birds and rodents. Seed predation is high. Some seed is probably buried by seed-caching animals, and unconsumed seed so buried may have higher rates of germination.

Vegetative regeneration - Bush chinquapin sprouts from the roots, root crown, and stump when aboveground portions of the plant are damaged.

Species Distribution


USDA Plants Database
USDA, NRCS. 2016. The PLANTS Database. National Plant Data Team, Greensboro, NC 27401-4901 USA.

USFS Plant Database
Habeck, R. J. 1992. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.

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.

The Jepson Herbarium
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.

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.