Soil Drenching of Bee-Killing Chemical Should Not Be Allowed

SafeLawns Objects to New Protocols for Exotic Invasive Insects

Soil drenching of toxic pesticides should never be allowed (forestryimages.org)

The existence of exotic invasive insects presents one of the biggest dilemmas of our time. When foreign creatures like the emerald ash borer, hemlock wooly adelgid or Asian longhorned beetle begin to decimate the urban and natural forest, few known natural or organic options exist for their treatment.

Asian Longhorn Beetle

So the question becomes: Do we let the insects have their way with our forests and landscape trees, or do we fight back with synthetic chemical tools that are known to help? These tools could, potentially, buy us time and preserve tree species while more environmentally friendly alternatives of treatment are sought out and researched.

For the three aforementioned insects, which are impacting hundreds of millions of acres of U.S. forests and neighborhoods, three primary chemicals have been approved by the federal government. When the chemicals are taken up by the tree, a resistance to the insects of two to four years may be the beneficial result.

Recently, a consortium of 20 tree-care companies, scientists and chemical manufacturers signed a protocol letter indicating that they agree with the three treatment options — dinotefuran is registered for basal trunk bark or soil application, emamectin benzoate for trunk injection only, and imidacloprid for soil application or trunk injection.

The SafeLawns Foundation has arduously and somewhat reluctantly come to agree with the position that chemical treatment is necessary to preserve tree species when exotic invasive insects are involved. Simply letting trees die, or cutting trees down before they die, has dire consequences for the planet.

The ArborJet injection system

We do not, however, condone soil drenching under any circumstances. The only responsible way to apply these chemicals — all known to have toxic side effects — is through trunk injection. The process has been vastly improved in the past decade by a Boston company known as ArborJet so that the chemical stays in the tree, with no leaking, and provides up to several years of insect control.

The soil drenching issue is especially critical with imidacloprid, which is from the family of synthetic nicotine products responsible for Colony Collapse Disorder in bees. When the chemical is drenched into the soil it is taken up by all the plants in the area, as well as the groundwater. When bees pollinate the plants or drink the water, they are affected by the imidacloprid.

When the imidacloprid is injected into the tree, the chemical stays in the tree. Parts per trillion of the chemical may fall to the ground inside the leaves in the fall, but by then the bees are almost finished with pollination for the season. The fact that ANY imidacloprid winds up in the soil from the leaves is not a good outcome — since infantesimal amounts of imidacloprid are bad for bees. But at least with trunk injection the least possible amount of the product will make its way into the soil.

Widespread soil drenching, as has been proposed in certain municipalities, will have dire consequences for the bee population.

If these exotic invasive insects are a problem in your municipality, tell your elected officials that you object to soil drenching of the chemicals. We’ll be happy to supply you with more information along the way.

It should be noted, too, that one natural botanic product derived from the Indian neem tree is showing great promise as a trunk injection tool in the fight against both emerald ash borer and hemlock wooly adelgid. Early tests are showing a solid rate of control. In America, that product is branded as Azasol.