Burlington Cuts Use of Pesticide That Harms Bees

Aug 16, 2016

The city of Burlington is stopping its use of a pesticide that harms bees, even before the official rules are written that could ban its use on municipal lands.

Earlier this year, Burlington passed a resolution to restrict the use of a class of pesticides called neonicotinoids in parks or any city-owned lands. The pesticide became popular as a spray and soil treatment in greenhouses because it's effective at killing pests, but isn't harmful to humans.

However studies suggest neonicotinoids are part of the cause of declining bee populations. 

The director of Burlington Parks, Recreation and Waterfront, Jesse Bridges, says the city is already using minimal amounts of pesticide.

"It was somewhat of an easy 'yes' for us, because I think we didn't have an ingrained culture of utilizing those type of products. But it is good to make that statement that it is something we're not going to use."

Bridges says the city is also working with its suppliers in effort to purchase plants that have not been treated with the so-called "neonics."

Garden retailers reduce pesticide use

The move comes as increased consumer awareness has also led many big-box retailers to phase out treating their plants with the chemicals. 

A recent study conducted by the advocacy group Friends of the Earth shows that use of neonicotinoids in large retailers has declined over the last year.

"They found that 23 percent of the plants they tested, that came off shelves from these stores, did have neonicotinoid pesticides, which is key contributor in recent bee declines," says Shaina Kasper, a community organizer with the Toxics Action Center.

These numbers suggest retailers are responding to some vocal consumers. For comparison, in 2013 and 2014, more than half the plants sampled contained traces of the pesticide.

The researched sampled 60 plants purchased at large retailers in 12 states, not including Vermont, though many of the stores were national chains that do sell in the state.

"This is very positive story, I'm very happy to hear that it happened within three years," says entomologist Vera Krischik of the University of Minnesota. Krischik has been studying the impact of these pesticides on bees for over a decade to figure out if even low doses could be harming bees.

"This shows how well democracy works, that scientists said something …  and that we all came to the conclusion there might be some effects [on bees] and to mitigate that we're asking that [retailers] don’t use these neonics — systemic insecticides — on plants that bees visit, and the industry has responded and has decreased the use."

Even small doses can effectively kill bees

Krischik says that when neonics are used in agriculture, the chemical is typically applied to the seed of plants like corn, soybeans, sunflowers, beets, canola and only a few milligrams are applied. 

"In greenhouse production, in a 3-gallon pot you can put in 300 milligrams—that's 150 times more," says Krischik. "There are much higher rates used in greenhouse production, and trees and woody plants like roses also have a high rate in the landscape."

The biggest problem, she says, is when neonics are applied to plants that attract pollinators, such as coneflowers, blazing star, salvias and Black-eyed Susans. Because the pesticide is systemic, it works its way up into the flower and pollen.

Krischik's research has shown that even low levels of the pesticide that don't kill bees, can confuse the bees so they stop foraging and the queen stops laying, and within two weeks the colony is drastically reduced.

Some retailers are beginning to label plants that have been treated with neonicotinoids, but this practice is voluntary. In some cases, retailers may not use the chemical themselves, but they may not be aware they have purchased seeds or seedlings that have been treated.