Ceanothus masonii
Encyclopedia
Ceanothus masonii is a species of shrub
in the buckthorn family, Rhamnaceae
, known by the common name Mason's ceanothus. It is endemic to Marin County, California
, where it is known only from an area near Bolinas
on the Point Reyes National Seashore
. It grows in the coastal chaparral
on the windblown bluffs.
is a small cluster of deep blue to purple flowers. The fruit is a capsule just a few millimeters wide, topped with minute horns. This ceanothus is closely related to Ceanothus gloriosus
, and may in fact be a variety of that species.
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
in the buckthorn family, Rhamnaceae
Rhamnaceae
Rhamnaceae, the Buckthorn family, is a large family of flowering plants, mostly trees, shrubs and some vines.The family contains 50-60 genera and approximately 870-900 species. The Rhamnaceae have a worldwide distribution, but are more common in the subtropical and tropical regions...
, known by the common name Mason's ceanothus. It is endemic to Marin County, California
Marin County, California
Marin County is a county located in the North San Francisco Bay Area of the U.S. state of California, across the Golden Gate Bridge from San Francisco. As of 2010, the population was 252,409. The county seat is San Rafael and the largest employer is the county government. Marin County is well...
, where it is known only from an area near Bolinas
Bolinas, California
Bolinas formerly Juggville is a coastal unincorporated community in Marin County, California in the San Francisco Bay Area. Bolinas is located west-southwest of San Rafael, at an elevation of 36 feet...
on the Point Reyes National Seashore
Point Reyes National Seashore
Point Reyes National Seashore is a park preserve located on the Point Reyes Peninsula in Marin County, California, USA. As a national seashore, it is maintained by the US National Park Service as a nationally important nature preserve within which existing agricultural uses are allowed to continue...
. It grows in the coastal chaparral
Chaparral
Chaparral is a shrubland or heathland plant community found primarily in the U.S. state of California and in the northern portion of the Baja California peninsula, Mexico...
on the windblown bluffs.
Description
This rare shrub grows to heights approaching 2 meters. The evergreen leaves are oppositely arranged and less than 2 centimeters long. They are round to oval in shape and have tiny, sharp teeth along the edges, sometimes spine-tipped. The inflorescenceInflorescence
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. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is a small cluster of deep blue to purple flowers. The fruit is a capsule just a few millimeters wide, topped with minute horns. This ceanothus is closely related to Ceanothus gloriosus
Ceanothus gloriosus
Ceanothus gloriosus is a species of shrub in the buckthorn family Rhamnaceae known by the common name Point Reyes ceanothus. It is endemic to California, where it is known from the coastline of the San Francisco Bay Area and areas north and south. It grows on seaside bluffs and the slopes of the...
, and may in fact be a variety of that species.