Berries were eaten fresh and also preserved. A tea made from the roots was used to treat diarrhea and dysentery (Clarke, p. 23; Strike, p. 135-136). 

Blackberries are still enjoyed by many people today, though it is best to wear gloves when picking to avoid the thorns. 

Information on growing California Blackberry (also known as Pacific Blackberry) can be found here on Calscape. 

California Blackberry provides food for a wide variety of wildlife including birds, insects, and mammals.