A View From the Woods ~ Insidious pesticide use harms pollinators

 

I don’t often mix the personal reflections of this column with my professional life. However, I recently worked on a project that revealed a huge environmental problem that is little known, even to the people who are involved in it. I behooves me to share what I have learned.

Many are aware of declining monarch butterfly populations, because we so rarely see them in our gardens in recent years. There has also been publicity about deaths of honeybee colonies and threats to the honey industry. Yet these are only two examples of the many kinds of pollinator insects which are becoming threatened, resulting in dangerously declining populations.

Pollinators, including bees, flies, wasps, ants, moths, butterflies and beetles, are essential for many environmental functions. It is the pollinators’ feeding habits which cause plants to pollinate and set seed. From important crops like alfalfa and fruit trees, to a whole range of wildflowers and trees, the world of plants depends on pollinating insects in order to survive. Humans depend on food, and 80% of the world’s crop species depend on pollination to set seed.

Scientists are madly trying to figure out the causes of pollinator decline. Loss of habitat, diseases, air pollution and climate change are part of the story. Pesticides used on crops are particularly suspected to kill or impair pollinators. The pesticide class of insecticides called neonicotinoids, is particularly toxic to bees.

Here is where our research came in to the story.

While much of the focus on neonicotinoid pesticide had been on spraying of crops, it turns out that the vast majority of neonicotinoid use is for treating seeds. The largest use is on corn seed.

It turns out that virtually all corn seed planted in the United States (with the exception of the 1-2% which is certified organic) is coated with a neonicotinoid seed treatment. When the seeder passes over the field, dust from corn seed can blow over to vegetation around the field. The pesticide becomes part of the growing plant and is present in the roots and leaves, and is left in the soil with crop residues. Pollinators which come into contact with even minute amounts of this insecticide can be gravely affected.

For soybeans, it is estimated that 80% of soybean seeds are treated, and in addition some soybean fields are also sprayed with neonicotinoids later in the summer to deal with aphids.

Just think about Fillmore County and our many acres of corn and soybeans. Most acres receive a dose of neonicotinoids every year. I recently flew straight south to Mexico for a little vacation, and it boggled my mind to think of the 94 million acres of corn and 83 million acres of soybeans in the United States, with most receiving neonicotinoids every year.

Some studies have shown no yield increase for farmers who use neonicotinoid-treated seed, unless there is a proven local insect infestation. So the added cost and environmental threat of the pesticide is not even justified by increased profits.

Three more facts may boggle your mind, as they did mine.

First, the U.S. Environmental Protection Agency does not regulate, or even track, treatment of seeds with neonicotinoids. They exempted such use years ago.

Second, many farmers do not choose this pesticide treatment, and in fact, up to a third are unaware of which pesticides are included on their seed. Labels and catalogs usually include trade names and pesticide mixes with little correlation to the active ingredients.

Third, if a farmer wanted to do the right thing and avoid neonicotinoids, they would have to search for non-treated corn seed and reserve untreated seeds early. Such seeds are difficult to find. Untreated soybean seed are somewhat easier to find, since the seed coat is usually applied locally. I see that Albert Lea Seed House sells pollinator-safe seed without neonicotinoid treatment, as well as organic seeds.

The Minnesota Legislature is now considering a bill to become the first state in the nation to address this problem. The bill would give the Department of Agriculture the authority to regulate seed treatment and ensure the availability of non-treated seed. Governor Dayton is to be commended for taking the lead with this proposal to address a looming and little-known environmental threat.