It is a resident of chaparral canyons, foothills, and lower-elevation mountains. One specialized habitat in which A. tomentosa is found is the Monterey Cypress forests at Point Lobos and Del Monte Forest in Monterey County, California.
This is a low-lying, spreading manzanita, generally quite a bit wider than it is tall. It is a variable species and even some of the subspecies can vary in appearance across individuals. The stems may be red or gray or both, with smooth, rough, or shreddy bark, hairless to quite bristly. The leaves may be oval to lance-shaped and sometimes toothed, but the upper surface is generally darker and shinier than the lower.
The flowers are white to pink and may be hairy or hairless inside. The fruits are fuzzy reddish drupes under a centimeter in diameter.
There are many subspecies:
- A. tomentosa subsp. bracteosa — uncommon subspecies from the vicinity of Monterey 
- A. tomentosa subsp. crinita — from the southern San Francisco Bay Area
- A. tomentosa subsp. crustacea — (brittleleaf manzanita), widespread
- A. tomentosa subsp. daciticola — (dacite manzanita), from San Luis Obispo County.
- A. tomentosa subsp. eastwoodiana — from Santa Barbara County
- A. tomentosa ssp. hebeclada — from southwestern Santa Cruz Mountains.
- A. tomentosa subsp. insulicola — (island-loving manzanita), scattered in the Channel Islands
- A. tomentosa subsp. rosei — (rosy manzanita), from the central and northern coasts
- A. tomentosa subsp. subcordata — (Santa Cruz Island manzanita), restricted to the Channel Islands
- A. tomentosa subsp. tomentosa — found along the Central Coast.
- California chaparral and woodlands — ecoregion.
- Calflora database: Arctostaphylos tomentosa . accessed 2.2.2013
- C. Michael Hogan and Michael P. Frankis. 2009. Monterey Cypress: Cupressus macrocarpa, GlobalTwitcher.com ed. N. Stromberg Archived 2017-09-06 at the Wayback Machine
- Jepson: A. tomentosa
- Calflora: A. tomentosa subsp. bracteosa
- Calflora: A. tomentosa subsp. daciticola
- Calflora: A. tomentosa ssp. hebeclada
- Calflora: A. tomentosa subsp. tomentosa
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