Ceanothus prostratus is a species of shrub in the Buckthorn family (Rhamnaceae) known by the common names prostrate ceanothus and mahala mat. It is native to the Pacific Northwest of the United States, into northern California and Nevada, where it grows in coniferous forest and open plateau. This is a flat, mat-forming shrub growing 6 inches tall up to about 8 ft. wide. The evergreen leaves are oppositely arranged, oval in shape with several large, sharp teeth along the edges. The upper surface is green and hairless, and the underside is paler in color and feltlike in texture. The flower cluster is a small cluster of deep blue or purple flowers. The fruit is a wrinkled capsule one half to one centimeter long.Ceanothus prostratus grows in the understory of mixed conifer forests, from foothills to subalpine areas. It also inhabits open flats and ridges in areas of low chaparral as well as dry interior forest ecosystems. It can be found from elevations ranging between 1,000 and 9,000 ft. It is notoriously difficult to grow due to unknown factors.