What's Bugging You?

Recently a friend asked me what she should do to get rid of the sand wasps colonizing her garden.

"Why do you want to get rid of them?" I asked. "They're dangerous," she told me. "I don't want to get stung!"

The bees my friend is seeing emerging from little chimneys in her yard are not dangerous and are not sand wasps, whatever those are. She is seeing a native insect commonly known as digger or miner bees.

Until recently, these bees had almost disappeared from our landscape. Read on and find out why.

Pollination refers to the transfer of pollen granules from flower to flower. Animals, including bees and other insects, play a crucial role as pollen transporters. Approximately 90 percent of our crops, producing over 30 percent of our food resources, are dependent on insect pollination. Bees are by far the most efficient pollinators. The value of bees, both as producers of honey and wax and enhancers of crop production, has been recognized for thousands of years. Honeybees were probably domesticated around 6,000 years ago in southern Asia. The Greeks and Romans both kept domesticated honeybees.

The occupation of beekeeping was practiced throughout Europe by the end of the Dark Ages. When Europeans took to the seas colonizing the New World, they carried with them many familiar domesticated animals, including the honeybee.

Swarming honeybees quickly escaped into the wild, establishing feral (wild) colonies across North America. Honeybees are highly adaptable and rapidly became important pollinators of wild plants as well as field crops. Unfortunately, these bees displaced many native insect species by taking their food, pollen and nectar.

Beginning in the second half of the 20th century, populations of wild honeybees declined throughout North America due to parasites, disease and environmental factors like weather and pollution. This decrease in population has been of great concern to farmers and scientists. Many researchers are looking for substitute pollinators. Nature has also taken steps to fill this void.

Several native pollinators that were once rare are making a comeback! One of these is the mining bee, also known as lawn bees, sand bees, digger bees and long horned bees (The males of some species have very long antennae.)

There are over 900 species of North American digger bees that pollinate many plant species. Mining bees are often drab in color but may feature spots of red, blue or gold. A few are metallic green. They are furry and vary in size. Most are about as large as a honeybee but the largest are as big as a bumblebee.

Unlike honeybees, digger bees do not live in colonies, but are solitary bees, which means individual females build their own nests. Each nest is lined with a shiny, wax-like material that is waterproof, highly resistant to decay, and protects larvae in the ground. Females sometimes build turrets or little volcano-like towers of soil at the nest entrance.

Often large groups of nests are located in the same area especially on the banks of creeks and in sandy soil. People working and playing near large groups of nests may become concerned. Digger bees are NOT aggressive and stings are very rare and reported to be mild. If left alone, digger bees will often nest in the same area year after year, and provide a service by pollinating garden plants to help ensure good crops. Some species also act as predators of insect pests.

To welcome these helpful residents into your garden, be careful to avoid disturbing their nesting area. You may wish to reserve an area of the garden for their use. Digger bees prefer warm, sandy areas of soil with a light mulch cover but lacking surface vegetation. Providing season long forage with flowering plants also encourages digger bees to remain.. Finally, take care not to contaminate plants and nests with harmful pesticides. Digger bees are helping provide a natural solution to the decline in wild honeybees.

Later on in the summer, especially on St. George Island, you may notice a larger hornet-like insect emerging from burrows in the ground. These frightening animals are Sphecid or digger wasps. Like digger bees, they are solitary, but usually nest in groups.

They may look frightening, but are docile. Think twice before you shoo them away. Some species of digger wasps feed their young paralyzed yellow flies.

Lois Swoboda, staff writer at the Apalachicola and Carrabelle Times, holds a doctorate in entomology from Virginia Tech. If you have question concerning a plant or animal you see in our area, you can ask the bug doctor by calling 653 1819, emailing lswoboda@starfl.com or dropping your written inquiry or a picture off at the Times office on Commerce Street.