Ceanothus integerrimus

Ceanothus integerrimus
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta
Class:	Magnoliopsida
Order:	Rhamnales
Family:	Rhamnaceae
Genus:	Ceanothus L.
Species:	Ceanothus integerrimus Hook. & Arn.

Ceanothus integerrimus

Ceanothus integerrimus Hook. & Arn., also known by the common name Deer Brush, is a woody dicot shrub native to the woodland areas of the United States west coast. It is a member of the Rhamnaceae, the buckthorn family, which contains 62 species of Ceanothus. Other varieties of C. integerrimus include, C. i. var. californicus (Kellogg) Benson, C. i. var. integerrimus, C. i. var. macrothyrsus (Torrey) Benson, and C. i. var. puberulus (Greene) Abrams [3].

C. integerrimus hybridizes with Ceanothus tomentosus, Lemmon’s Ceanothus and Ceanothus cordulatus, Wooly Leaf Ceanothus.

Habitat

C. integerrimus occurs in Arizona, New Mexico, California, Oregon, and Washington in the United States. However, C. integerrimus occurs most abundantly in California [4]. Numerous species of Ceanothus attribute to much of California’s chaparral growth.

C. integerrimus grows in chaparral mountain shrub regions, in hardwood forests of the west, and in Fir, Spruce, and Ponderosa pine communities [8], [4].

Characteristics

C. integerrimus is a shrub with an open branch habit that grows from 3 to 18 feet tall. It is a deciduous shrub and is drought tolerant phanerophyte. Nitrogen fixing bacteria, actinomycetes, form root nodules on Ceanothus roots [2], [5].

C. integerrimus is an ascending to erect plant. Its stems are round yellow to a pale green in color with either small soft to straight stiff sharp hairs parallel to or in contact with the surface of the stem [4], [6].

Leaves of C. integerrimus are glossy, deciduous and about 8 centimeters long. Leaves grow alternately on stems. Petioles of leaves are less than 15 millimeters in length and the stipules of the plant are also deciduous. Leaf blades are lanceolate, elliptical or oblong to widely ovate in shape. Leaves can have one to two ribs from the base; they are also generally thin and have an acute to obtuse tip. Leaf margins are either entire or slightly dentate, more so towards the leaf tip. Leaf surfaces are light green and are ciliate or contain hairs visible only by magnification. Lower leaves are also hairy and lighter in color [4].

Flowers of C. integerrimus are white or blue and rarely pink in color. Flowers are raceme clusters of 15 centimeters or less and contain both male and female organs.

Fruits are sticky valves about 4-5 mm in diameter and are slightly crested.

The following varieties C. integerrimus are not well identified. Identification is primarily by leaf morphology and flower color [4], [5]:

C. i. var. californicus (Kellogg) Benson; leaves are elliptic, lanceolate or oblong to ovate in shape and are three ribbed, from the leaf base. Leaf surfaces have small hairs and the undersides are less hairy than the surface. Flowers are generally white or blue.

C. i. var. macrothyrsus (Torrey) Benson; leaf blades are oblong or ovate. Leaf bases are three ribbed at the base. Leaf surfaces are pubescent on both the surface and undersides. Flowers are white.

C. i. var. puberulus (E. Green) Abrams; leaf blades are elliptical or lanceolate and oblong to obovate in shape. Leaf base is three ribbed from the leaf base. Leaves are also pubescent on both sides. Flowers are white in color.

Regeneration

C. integerrimus regenerates by seed, shoot formation from the crown and stem and also by layering when branches come in contact with soil [3], [5]. It has been suggested that some Ceanothus species do not respout from the root after the crown has burned as a result of fire were most other species are able to regenerate [10]. Pollination of flowers is primarily by bees.

Seed production occurs after about for years of age and is ejected from capsule after splitting. High densities of seeds occur in the upper soil of Ceanothus communities. Seeds remain viable up to 24 years or more. Seed dormancy is broken by the removal of the seed coat by fire scarification or physical disturbance [3], [5]. Seeds germinate best at about 1 inch soil depth in shady areas in the spring following fire scarification [3], [5].

Ecology

C. integerrimus is an important part of forest regeneration after fires by providing nitrogen [1]. It does this by creating nitrogen rich patches in the soil. The nitrogen source is created by its root association with nitrogen fixing bacteria [8].

Deer and specifically mule deer feed on C. integerrimus. Porcupines and quail have also been observed eating stems and seeds of this shrub [11]. Nutritionally leaves are a good source of protein and stems and leaves also contain high levels of calcium. However, nutritional quality of leaves is seasonal and appears to be best from fall to early spring [5].

Uses

Medicinal uses of C. intergerrimus branches among North American Indians of California are used in treating women after childbirth [7]. Miwok Indians of California also use the branches of this plant in making baskets [5].

References

1. Debano, L. F.; C.E. Conrad, 1978. The Effect of Fire on Nutrients in the Chaparral Ecosystem. Ecology; 59:3 pp. 489-497.

2. Gibbens, R, R. P.; Schultz, A. M. 1963. Brush manipulation on a deer winter range. California Fish and Game; 49:2, pp. 95-118. [5976].

3. Griffin, James R. 1982. Pine seedlings, native ground cover, and Lolium multiflorum on Marble-Cone burn, Santa Lucia Range, CA. Madrono;29:3, pp. 177-188.

4. Hickman, A. James; Hooke & Arn. (p. 941). The Jepson Manual. University of California Press: 1993; p. 936.

5. Howard, Janet L. 1997. System Ceanothus integerrimus In: Fire Effects Information [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. # http://www.fs.fed.us/database/feis/.

6. Munz, Philip A.; David D. Keck. A California FLORA with Supplement. University of California Press, Berkely, Los Angeles CA: 1959; p 973.

7. Moerman, D. Native American Ethnobotany. Timber Press, Oregon: 1988.

8. Oakley B. Brian; Malcolm P. North and Jerry F. Franklin, 2003. The effects of fire on soil nitrogen associated with patches of the actinorhizal shrub Ceanothus cordulatus. Plant and Soil; 254: 35-46.

9. Oswald, Vernon H.; Lowell Ahart. Manual of the Vascular Plants of Butte County, California. Native Plant Society, Sacramento, CA: 1994. p.192.

10. Raven, Peter H.; Daniel I. Axelrod. Origin and relationships of the California Flora. University of California Publications in Botany 72. Sacramento CA University of California Press: 1977.

11. Russell; Carl Parcher, 1932. Seasonal Migration of Mule Deer. Ecological Monographs; Jan 2:1 pp.1-46.