There are so many kinds of native bees, in addition to the introduced honeybee. They've been fun to learn about and observe in different flowers.
The big carpenter bees with their smooth black abdomens are the biggest, except for the occasional queen bumblebee. They visit a variety of different flowers, and are strong flyers. They're not above 'robbing' nectar from Salvias, either, poking holes at the base of the flowers, thereby circumventing entering the flower 'correctly'.
All of the smaller bees are fun to watch gathering pollen. These were visiting native Helianthus hirsutus and Rudbeckia fulgida flowers in the meadow. 
There's a specialist bee that collects pollen from these portulaca flowers in one of my containers, but I wasn't able to catch it in a photo.
