Ceanothus integerrimus description

Ceanothus integerrimus

W. J. Hooker & G. A. W. Arnott, Bot. Beechey Voy. 329. 1840

Deerbrush

Ceanothus andersonii C. C. Parry; Ceanothus californicus A. Kellogg; C. integerrimus W. J. Hooker & G. A. W. Arnott var. californicus , (A. Kellogg) G. T. Benson; Ceanothus integerrimus W. J. Hooker & G. A. W. Arnott var. macrothyrsus (J. Torrey) G. T. Benson; Ceanothus integerrimus W. J. Hooker & G. A. W. Arnott var. puberulus (E. L. Greene) L. Abrams;

Description:

Habit: Shrubs to 4 m.

Stems: ascending-erect, not rooting at nodes; twigs yellow- to pale green, round, smooth, glabrous to +/- strigose, flexible.

Leaves: deciduous, alternate, not clustered; stipules thin, deciduous; petioles to 15 mm; blades lanceolate, elliptic or +/- oblong to broadly ovate, 2.5--8.0 x 1.0--3.9 cm; bases rounded, 1 or 3-veined, margins not revolute, usually en tire or minutely denticulate towards tip, tips acute to obtuse, abaxially pale green, +/- pubescent, especially on major veins, adaxially light green, +/- glabrous to pubescent, plane.

Inflorescences: usually terminal,raceme-like, 4.0--15.0 cm; flower clusters usually stalked, some single clusters axillary in leaflike bracts.

Flowers: white, pale to dark blue, rarely pink.

Fruits: globose to trihedral, summit +/- depressed, 4--5 mm broad, sticky, horns 0; valves minutely crested.

Cytology: n = 12 (M. A. Nobs in H. E. McMinn 1942)

Flowering: in spring--summer.

Habitat: Dry slopes and ridges; 300-2100 m.

Range: Ariz, Calif., N.Mex, Oreg., Wash. View distribution map.

Other Information:

Several poorly defined vars. have been recognized. These various morphs seem to occur in response to water availability and disturbances, such as fire.

var. integerrimus (lf blade oblong to elliptic-oblong, gen 1- ribbed from base, fl white or blue; Calif. SnFrB, SCoR,);
var. californicus (Kellogg) Benson (lf elliptic or lanceolate to oblong-ovate, 3-ribbed from base, upper side gen glabrous, lower glabrous or hairy; fl white; Calif. KR, NCoR, CaR, SN;
var. macrothyrsus (Torrey) Benson (lf blades oblong to ovate, gen 3-ribbed from base, gen hairy both sides, fl white to blue; Calif. KR, CaRH, Oreg., Wash.);
var. puberulus (E. Greene) Abrams (lf blade elliptic or lanceolate to oblong-ovate,, 3-ribbed from base, gen hairy on both sides, fl white; Calif. TR, PR ).

Coile in her unpublished doctoral dissertation dealing with the deciduous ceanothuses, placed all of the Ceanothus integerrimus varieties into synonomy with the species. [N. C. Coile 1988]

If you have any comments or information regarding this species, please send mail to Dr. Schmidt.