Solitary Bees of Springtime

by Andrea Laine, EMGV

Say ‘bee’ and many of us think bumble or honey. But at this time of year we are apt to see ground-nesting bees out and about our landscapes, visiting the same early spring flowering plants that a honey bee might pollinate.

Ground-nesting bees are native solitary bees that nest individually in polyester-lined tunnels or burrows at least six inches deep in warm, dry ground. Reflective of this behavior, they are also called mining bees or digging bees. They are more likely to nest in areas with exposed soil and sparse vegetation, not dense turf or mulched beds.

MiningBee_M.Bertone
There are many species of bees that nest in the ground and they range in size and color. Pictured here is an adult mining bee. Photo by M. Bertone. 

 

TBilleisen ground bee damage
Evidence of ground nests can resemble tiny ant hills. Photo by T. Billeisen.

A hospitable patch of ground is likely to house a number of solitary tunnels, thus giving the impression at times of a small swarm of low-flying bees. But these bees are not aggressive as they are not defending a hive (as honeybees and bumblebees would be). And, as is the case with all bees, males cannot sting.

For two to four weeks in mid to late spring, females collect pollen and nectar to bring back to the nest. With it they form a ball in the side of the tunnel. They lay a single egg on the ball and when it hatches, the larva feeds on the pollen and continues to develop until the following spring when it emerges from the ground as an adult bee and goes forth to build a new nest.

Solitary bees are beneficial insects: They pollinate plants and their burrowing behavior is hardly noticeable and does no damage. On the contrary, it helps aerate the soil.

 

Sources & Further Reading

Matthew Bertone, Plants, Pests and Pathogens, Feb 26, 2019

https://www.turffiles.ncsu.edu/insects/bees-in-turf/

https://caldwell.ces.ncsu.edu/2014/06/ground-digging-bees/

http://www.gardening-for-wildlife.com/ground-bees.html