Long-horned bees of the tribe (Eucerini) genus Eucera Subgenus Synhalonia
These little bees look like a honey bee until you pay attention. They are fast and intelligent. They have antenna for long range floral quests.
Long Horned bees live in the ground in vertical tubes on flat ground with side galleries of individual cells for each egg that is lined with pollen and nectar and plugged up with packed dirt when done. The entrances are about 6-7 mm.(1/2 inch) across and maybe 35-40 cm(a foot) deep.
They need weed free ground that is not cultivated to thrive.
(Nests of Tetralonia lepida (Hymenoptera, Anthophoridae)
Robert W. Brooks and Charles D. Michener
Journal of the Kansas Entomological Society
Vol. 58, No. 3 (Jul., 1985), pp. 559-561 )
Eucera Subgenus Synhalonia a Long Horned bee on Arctostaphylos stanfordiana