Identificaciones de jdowning

This was a rather large manzanita with leaves I had never seen before. Full in flower there were a pair of bees that seemed to be protecting the shrub. Anytime another pollinator would visit a blossom the bees would fly over and make the intruder buzz off. Watched the behavior for about 10 minutes not exactly sure what I was witnessing, but very interesting none-the-less. The bees were very dark almost black, but didn't seem to me to be carpenter bees. The manzanita I'm not entirely sure on either possibly Arctostaphylos pallida