''Ceanothus tomentosus'', with the common name woollyleaf ceanothus, is a species of

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

in the family

Rhamnaceae The Rhamnaceae are a large family of flowering plants, mostly trees, shrubs, and some vines, commonly called the buckthorn family. Rhamnaceae is included in the order Rosales. The family contains about 55 genera and 950 species. The Rhamnaceae h ...

. It is characterized by pale-blue to deep blue flowers and wooly leaves. It is native to

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

, having an unusual disjunct distribution in the

Peninsular Ranges The Peninsular Ranges (also called the Lower California province) are a group of mountain ranges that stretch from Southern California to the southern tip of the Baja California peninsula; they are part of the North American Coast Ranges, which ...

and the north-central

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily ...

Description

''Ceanothus tomentosus'' is an erect

(occasionally tree-like) approaching 3 m in maximum height. The

wood Wood is a porous and fibrous structural tissue found in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulose fibers that are strong in tension and embedded in a matrix of lignin th ...

y parts are reddish or brown, especially when new. The

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...

leaves are alternately arranged, elliptic to oval in

shape A shape or figure is a graphics, graphical representation of an object or its external boundary, outline, or external Surface (mathematics), surface, as opposed to other properties such as color, Surface texture, texture, or material type. A pl ...

, dark green and with short

hairs Hair is a protein filament that grows from follicles found in the dermis. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and f ...

on the top and woolly on the undersides. The leaves have a petiole 1 to 3 mm long, with the leaf blade 10 to 25 mm long, 5 to 12 mm wide. The margins of the leaves are

serrated Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied pr ...

with 40 to 60 tiny glandular teeth. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is a cluster several centimeters long of pale blue to deep blue flowers. The fruit is a lobed capsule a few millimeters long which is sticky when new.

Characteristics

Diagnostic features include the leaves being 3-ribbed from the base, the leaf veins being more or less obscured by the

, and the teeth on the edge of the leaf being tipped with

glands In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure De ...

, which sets it apart from plants like ''

Ceanothus cyaneus ''Ceanothus cyaneus'' is a species of flowering shrub in the genus ''Ceanothus'' known commonly as the San Diego buckbrush and Lakeside ceanothus. This species is found in the Peninsular Ranges of San Diego County, California, and known from one ...

''. The twigs on this species are also flexible and not thorn-like, as opposed to species like ''Ceanothus leucodermis'' with rigid, thorn-like twigs. File:Ceanothus tomentosus 20044970.jpg, Note the conspicuous black glands on the teeth of the serrated margins File:Ceanothus tomentosus 70049335.jpg, The 3-ribbed base of the underside of the leaf File:Ceanothus tomentosus 30171093.jpg, Note the glandular teeth and the venation

Taxonomy and phenology

This species was described by

Charles Christopher Parry Parry circa 1875 Charles Christopher Parry (August 28, 1823 – February 20, 1890) was a British-American botanist and mountaineer. Biography Parry was born in Gloucestershire, England, but moved to the United States with his parents in 1832, s ...

in 1889. It is within the ''

Ceanothus ''Ceanothus'' is a genus of about 50–60 species of Actinorhizal plant, nitrogen-fixing shrubs and small trees in the buckthorn family (Rhamnaceae). Common names for members of this genus are buckbrush, California lilac, soap bush, or just ceano ...

'' subgenus ''Ceanothus''. The specific epithet ''tomentosus'' refers to the dense, interwoven trichomes on the plant. Although the ''Ceanothus'' subgenera vary in their preference to sprout from

lignotuber A lignotuber is a woody swelling of the root crown possessed by some plants as a protection against destruction of the plant stem, such as by fire. Other woody plants may develop basal burls as a similar survival strategy, often as a response t ...

s (resprouting) versus seeds (nonsprouting) after

fire Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products. At a certain point in the combustion reaction, called the ignition ...

, ''Ceanothus tomentosus'' exhibits both resprouting and nonsprouting plants across its range. Plants in the

section of the distribution resprout after fire, while plants in the

Southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...

area of distribution are nonsprouters. Nonsprouting populations tended to have an earlier onset of flowering as well. Ceanothus tomentosus 31275666

Distribution and habitat

This species is distributed in both the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

and

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. In the United States, it is found in the state of California, in the

, but also with a disjunct distribution in a portion of the north and central

and its foothills. In Mexico, this species is found in the northwestern part of

, from

Tijuana Tijuana ( ,"Tijuana"
(US) and < ...

to the southern end of the Sierra de San Pedro Martir. This plant primarily occurs on open sites on slopes, ridges, chaparral, and coniferous forest.

References

External links

Jepson Manual Treatment - ''Ceanothus tomentosus''USDA Plants Profile: Ceanothus tomentosus''Ceanothus tomentosus'' - Photo gallery
{{Taxonbar, from=Q5055742 tomentosus Flora of California Flora of Baja California Flora of the Sierra Nevada (United States) Natural history of the California chaparral and woodlands Natural history of the Peninsular Ranges Plants described in 1889