Nesting bees can benefit a garden

Q. Why are bees burrowing into the ground around my garden?

A. Can you believe that 70 percent of the solitary bee population nests in the ground? Actually, having ground-nesting bees in your garden is very beneficial!

They aerate the soil, pollinate the plants and are predators to harmful garden pests. Female ground bees are digging nests to raise their young and stocking the nest with pollen and nectar to feed them. Still, if there are a number of bees swarming around and living underground it can be disturbing. Generally, they are NOT aggressive but there is always a concern for getting stung.

Identify your stinging insect before you control them. There are websites available to explain what type of insect you are dealing with. Ground bees are not aggressive but similar looking bees and wasps are very aggressive. The biggest difference between the ground bees and other bees and wasps is that ground bees live by themselves and will make many holes in the ground. Yellow jackets and bumblebees will have many bees yet one hole.

What is attracting them to your garden is the sandy barren area of ground where they make little mounds of soil at the hole entry. Mulching this area makes it less attractive to these ground nesters.

They will also nest in thin turf grass so working to enhance the lawn turf will deter them in that area. Keeping the soil moist with one inch of water once a week in the area is also less appealing to them as they prefer dry soil.

Chemical control is not recommended for ground nesters. The bees are generally harmless and chemicals are toxic. They typically are around for four to six weeks and then disappear until next year. They are very efficient and effective pollinators in your garden.

For more information on ground nesting bees, visit the following useful sites:

• extension.illinois.edu/hortihints/0306d.html

• www.dnr.illinois.gov/publications/documents/00000834.pdf

• chicagolandgardening.com/docs/legacy/cgm-pages/seasonal-stories/htm/NativeBees_MA2013.html

• Provided by Master Gardeners through the Master Gardener Answer Desk, Friendship Park Conservatory, Des Plaines, and University of Illinois Extension, North Cook Branch Office, Arlington Heights. Call (847) 298-3502 Monday, Wednesday and Saturday or (847) 201-4176, ext. 14, on Fridays.