By Margot Monson
As biologist E. O. Wilson put it, insects are the “little things that run the world.”
The most abundant of all animals, insects are the foundation of our ecosystems and in ecosystems, diversity counts. But with climate change and habitat loss, we’re losing species diversity, including insects.
What can we do? Close to home, we can make a difference with our own yards and container gardens. If we design healthy habitats for all living things, we can sustain insects and regenerate our own little piece of the world.
Nectar and pollen
Native perennials evolved with the insects they depend on for pollination. Insects, in turn, depend on the plants for nutritious nectar, and some insects, like bees, feed pollen to their young. In fact, bees have adapted to intentionally carry pollen, while most insects transfer pollen inadvertently, only pollinating when they visit the same species of flower repeatedly.
However, not all pollen and nectar sources are created equal. Most annual plants don’t have the protein-rich pollen that bees need to raise their young, or the nectar other pollinators need for energy. For that, you need deep-rooted perennials.
Native bees are essential to pollination in our ecosystems, and they depend on high-quality pollen and nectar. So, when you plant native perennials, you create habitat for a diversity of insects. It’s not just bees and butterflies, but moths, flies, beetles, wasps, lacewings and many that prey upon other insects.
And you’ll attract insects that turn organic matter into healthy soil, such as those inhabiting compost piles. With enough native plant diversity, you’ll have very few pest insects. If you choose different varieties of plants that bloom consistently, they’ll provide the balanced diet bees need throughout the season, helping keep their immune systems strong.
Native bees: Our local heroes
We’re all aware that honeybees—originally imported to Minnesota by European settlers—are in steep decline. Less well-known are the hundreds of native bee species suffering from decline. And it’s these native bees and other native pollinators that sustain our woodlands, prairies, deserts, wetlands and bogs. Native bees pollinate many plants that honeybees can’t, being better suited to certain flower structures. Bumble bees pollinate tomatoes, blueberries, eggplants, potatoes and cranberries, as well as flowers like turtlehead, bottle gentian and shooting stars.
You may know the rusty patched bumble bee was named Minnesota’s state bee last year. It’s now rare, and researchers are finding several other native bumble bees also declining.
Although they’re most recognizable, bumble bees account for just 20 of about 470 native bee species in Minnesota. Bumble bees nest together underground in colonies with a queen, many female workers and a few drones. But most native bees are solitary.
Each spring, single females emerge to build small nests in underground tunnels or in hollow stems or other hidden places. They supply the nests with pollen and nectar, lay their eggs, seal the entrances and leave. Bee larvae consume the food, spend the rest of the season in the nests and emerge as adults the next year. They’re smaller than most bumble bees and often go unnoticed; they don’t sting, either. They are essential for the priceless work of pollination.
So please, do our native bees a favor this year: Give them nesting habitat. Leave a few bare places in your yard that will be undisturbed all season. Keep a few logs or sticks tucked away in a corner, or leave some dried perennial stems standing upright through the season. And keep your lawn or garden free of chemicals.
Tips for a pollinator-friendly garden
As you prepare for the growing season, here are a few ideas.
Choose plants friendly to pollinators with at least some native perennials that offer high-quality nectar and pollen. For recommendations, visit www.beelab.umn.edu/flowers. If you plant annuals, choose pollinator-attractive ones like Dakota Gold (Helenium), Showstar (Melampodium), Orange Fudge and Prairie Sun (Rudbeckia), Lemon Queen or Music Box Mix (Helianthus), Summer Jewel Pink and Purple Fairy Tale Salvia and Envy Zinnia.
Avoid chemically treated plants and seeds. Ask the seller about the source, and don’t buy anything pre-treated with pesticides, herbicides or fungicides. Many of these are systemic. Their pollen and nectar pass the poisons along, leaving insects with weakened immune systems. Take extra care to choose chemical-free trees and shrubs, as their sources are harder for sellers to track. Visit www.pollinatorfriendly.org under “Habitat and Gardening” for lists of local suppliers of untreated plants.
Participate in Lawns to Legumes. A growing number of our local boulevards have been converted from grass to flowering plants. (Mine after three years is still a work in progress, as I figure out which plants can evade the grazing wild turkeys.)
During the 2019 legislative session, several of us worked to pass the Lawns to Legumes bill that is now providing funds and guidance for homeowners to convert conventional lawns to pollinator forage, which includes flowering perennials, trees and even fescue that can be mowed. Visit BlueThumb.org to apply for funding and learn about choices that produce flowers, attract pollinators and fix nitrogen, eliminating the need for fertilizers. More details are on the Minnesota Board of Water and Soil Resources website under “Lawns to Legumes.”
Together, we can “bee the change” for the insects and native plants that sustain the planet’s ecological integrity.
Margot Monson, of St. Anthony Park, is an entomologist and beekeeper who welcomes insect questions. To see more of her pollinator photos, visit TransitionASAP.org/sustainable-food.