Supporting a diversity of pollinators is important, as different bees can pollinate different flowers. For these reasons, supporting local bee habitats is so much more than just thinking about honey bees.
Cavity nesting bees are extremely effective pollinators for native plants - even more so than honey bees, who are not native to the Americas.
Leafcutter Bee
Around 70% of native solitary bee species nest below ground, in holes they dig, rock cavities, or holes dug by other species, such as rodents. The remaining 30% nest in above-ground cavities, such as holes in wood, or hollow stems.
A leafcutter bee with a nest among rocks
A bee emerging from a nest in a seed pod
We can support native bees by providing the materials and cavities they need to nest.
HealthyLoose dirt, leaf litter, and Natural cavities are often built with leaf litter, healthy dirt, rock piles and by leaving dry perennial stems standing.
Artificial cavities can be made of various materials. In the past, "bee hotels" have been made of tightly-packed bamboo reeds and/or holes drilled in wood. Unfortunately, these have been found to be susceptible to parasite outbreaks.
Historically-popular bee hotel, which has parasite risk
Chaetodactylus krombeini, a parasite of Blue Orchard Mason Bees
Many bee advocacy groups now advise against using bamboo "bee hotels", and against the practice of drilling holes into wood blocks, because these types of homes can be difficult to clean out every year, leading to parasite populations that persist and grow year after year.
Instead, they advocate for using disposable paper tubes, or homes that can otherwise be disassembled and cleaned.
It's useful to reflect on the natural homes of these bees, as well as the diseases and parasites they encounter to determine which type of artificial home is best for bees in your area.
For example, some of these bees naturally live in the hollow stems of perennial plants, where their homes would naturally be degraded and renewed each year. In this case, mites would not have a chance to easily camp out in their homes and move from one generation to the next.
Some bees in cavities that persist year to year and encounter different diseases and parasites.
Find the particular bees in your area to learn how you can best help.
