Ask Before You Buy: Bee-Friendly Plants Might Kill Instead

There's a lot of buzz about the importance of pollinators to our food system and a big push for home gardeners to include more bee-friendly plants. Some of your neighbors, like mine, might be looking to get their yards officially certified as officially bug-friendly habitats. So it's time to start making lists of the plants and seeds we need, then head to the nursery, right?

Well, pause a moment in that list-making, friends, because what you may not be aware of is that some of those lovely plants at the nursery labeled as "bee friendly" might actually be harmful or even toxic to pollinators. Remember last year when a Wilsonville landscaping company sprayed dozens of blooming linden trees, killing more than 50,000 bumblebees? The insecticide they used to spray the trees—apparently without reading the instructions, which strictly forbade using it on trees in bloom and which the company was subsequently fined a bit more than $2,800, about a nickel a bee—is one that is often used on landscaping plants.

Called a neonicotinoid, or "neonic" (pron. NEE-oh-nick), it's a systemic chemical that's absorbed by the plant and dispersed through the plant tissues, including pollen and nectar. Developed to target nerve impulses in insects and other invertebrates, neonicotinoids are deemed "safe" since harm to humans and other mammals is minimal. However, neonicotinoids are toxic to bees and many other beneficial insects and can linger in the soil for months or even years, where they can be picked up by the next season’s plants.

Even when used according to printed instructions, the concentration of neonicotinoids in garden products can be dozens of times greater than the amounts found on farm crops. This means that bees can be exposed to lethal doses of neonicotinoids in gardens. Even if bees are not killed outright, smaller, nonlethal doses can impact their health, causing bumblebee colonies to grow more slowly, produce fewer queens and impair honeybees' ability to fly, navigate and forage for food.

Only one nursery in the Portland area, Garden Fever on NE Fremont, has pulled all pesticides containing this group of chemicals from its shelves. At any of the other garden stores it's important to ask staff people if the plant you're buying has been treated with systemic pesticides at the wholesale nursery or grower, or if that grower uses neonicotinoids in spray form or as granules (since they can travel through the air or linger in soil). If the staff doesn't know or isn't sure, you can call the distributor, but your best bet would be to buy organic plants and starts to be sure.

Above all, according to Mace Vaughan, Pollinator Program Director at the Xerces Society, "folks should be looking for alternatives to pesticides, which means using no long-lived neonics and learning how to apply the least harmful methods." He highly recommends consulting Metro's Natural Gardening website. (Download Metro's natural gardening guide.)

If you want to take that a step further and get active in the effort to classify neonicotinoid pesticides as "restricted use" in Oregon—which would mandate that any commercial use (e.g. at a greenhouse) requires a trained applicator—you should contact your state representative. As it stands now, Vaughan says, "if I owned a nursery in this state, my 11-year-old daughter could go out and spray everything with neonics. Common sense dictates that trained applicators should be the only ones do this, which dovetails with the new law (HB4139) passed in the last legislative session requiring that trained applicators learn about bee protection."

For more information on neonicotinoids and their use, download the Xerces Society's brochure, Protecting Bees from Neonicotinoid Insecticides in Your Garden.

Top photo: buff-tailed bumblebee (bombus terrestris) by Alvesgaspar from Wikimedia Commons.