Every year, more than $20 billion dollars of food crops are produced across North America because of pollinators. Unless you’ve been sleeping under a rock, you know about the dramatic decline in European honeybee populations.
While becoming a beekeeper and maintaining a honeybee hive of your own may not interest you, there are some things you can do to help both your own garden and farmers everywhere by supporting our native pollinators.
North America is home to thousands of species of native bees. They, too, are becoming victims of pesticide exposure, diseases and habitat loss. Most native bees are solitary, rather than living in large colonies like European honeybees, and they are often more-efficient pollinators.
For example, 250 female orchard mason bees can pollinate an acre of apple trees, a task that requires 15,000 to 20,000 European honeybees. Most of these little bees are very docile and gentle and do not sting. They are a diverse crew — with names like mining, digger, sunflower, mason, leaf-cutter, carpenter and squash bees. Some of our native bees can be nondescript, while others shine like iridescent green jewels or have bright stripes.
Here are a few small steps you can take to support and encourage native pollinators.
• 1. Protect any habitat you may already have in place by preserving undisturbed, wild areas that can serve as sources of nectar and habitat. Rock piles, heaps of brush, snags, hollow-stemmed plants and bare ground all serve as possible nesting sites and should be protected. Some 70 percent of native bees nest in the ground, while most of the remaining species nest in hollow plant stems and other above-ground openings.
These native bees are not the same as the ground-dwelling yellow-jacket wasps we often call “ground bees.” The two should not be confused. Yellow jackets live in large colonies and will sting if provoked, while most native bees go mostly unnoticed and are incapable of stinging.
• 2. Next, examine your garden-management practices. As native bees are sensitive to pesticides, start by converting to natural pest-management practices and eliminating chemical pesticides. Tillage practices also can impact native bees. Because a significant number of native bee species nest in the ground, no-till gardening definitely has a positive impact on their numbers.
A study in Virginia looked at pumpkin and squash pollination and found that where no-till practices were in place, there were three times the number of pollinating squash bees. These large, solitary bees nest in the ground right next to the plants they pollinate and are responsible for 80 percent of squash pollination. If you don’t want to switch to no-till gardening, allow areas with plenty of exposed soil to remain undisturbed, and don’t mulch every strip of bare ground, especially south-facing slopes where certain bees prefer to nest.
• 3. Create new pollinator habitats for nectar foraging. Plant a diversity of native plants with successive bloom times, varied flower shapes and diverse coloration. The more variety, the better.
• 4. Add artificial and natural nesting sites for tunnel-nesting bees. You can purchase or build nesting tubes, tunnels and blocks, or plant plenty of hollow-stemmed plants, like elderberries, box elders, Joe Pye weed, teasels, brambles, cup plant and bee balm for them to naturally nest in. Homemade or commercially purchased wooden nesting blocks or stem bundles can be placed in a sheltered site with morning sun. They can be left in place year-round but should be replaced every few years.
Follow these simple steps to make a huge impact on the health of all our native pollinators.
Horticulturist Jessica Walliser co-hosts “The Organic Gardeners” at 7 a.m. Sundays on KDKA Radio. She is the author of several gardening books, including “Attracting Beneficial Bugs to Your Garden: A Natural Approach to Pest Control” and “Good Bug, Bad Bug.” Her website is www.jessicawalliser.com.
Send your gardening or landscaping questions to [email protected] or The Good Earth, 503 Martindale St., 3rd Floor, D.L. Clark Building, Pittsburgh, PA 15212.