Neonicotinoids

Neonicotinoids are a class of insecticides.

When neonicotinoids first came on the market in the 1980’s, they were touted as a cure-all for garden pests around the world. Since neonics affect certain receptors in an insect’s nervous system, humans and other mammals, birds, and fish would be perfectly safe, they said. That sort of marketing should have been a warning from the beginning. What quickly followed were massive bee die offs, and threats by the EU to regulate this class of chemicals, but it's not that simple. To understand the pros and cons of this insecticide, we need to know more about how it works.

​What are neonicotinoids?

Neonicotinoids, or neonics, as they are more conveniently known, are a class of insecticides that are chemically similar to nicotine. This class of chemicals includes several ingredients you may see on a bottle of insecticide:

• acetamiprid
• clothiandin
• imidacloprid - most commonly used insecticide, globally
• nitenpyram
• nithiazine
• thiacloprid
• thiamethoxam

After the disaster of DDT, other chemical insecticides were tried. Organophosphates and carbamates were the most common, but these are far more toxic than the neonics. By 2013, according to YaleEnvironment360, 95% of the U.S. corn and canola crops, most of the cotton, sugar beet, and sorghum crops, and a “vast majority of fruit and vegetables, including apples, cherries, peaches, oranges, berries, leafy greens, tomatoes, and potatoes, to cereal grains, rice, nuts, and wine grapes” were sprayed with neonics.

How do neonics work?

Neonicotinoids work by interrupting an insect’s nervous system. Since insect nervous systems are so different from other living things, these chemicals are generally safe, as far as poisons go. Initially, plants and seeds were sprayed with neonicotinoids. Neonics are systemic, which means they can be sprayed on seeds or plants, or watered in. Sprayed seeds grow into plants that contain the insecticide. Sprayed plants absorb the chemical, which is then spread throughout the plant via the xylem. When an insect comes along and takes a bite, or grabs some nectar or pollen - WHAM! They’ve been poisoned.

​Problems associated with neonics

The initial problems with neonics occurred when seeds were sprayed with the chemical and then put through a seed spreader that created clouds of neonicotinoids, killing tens of thousands of honey bees. Also, sprayed insecticides tend to go all over the place, causing overspray damage to nearby plants, waterways, and air. Of course, all this made the news and got everyone excited, but those particular problems have been resolved in most countries.

Now, neonics are more commonly applied as a drench, which is poured into the soil, to be absorbed by the roots. This eliminates overspray. Treated seeds are now managed in ways that prevent the pneumatic seed dispersal issue. Currently acceptable application rates seem to only be causing minimal harm to honey bee colonies, but they are still devastating to native bee populations.

Does your garden really need chemicals?

Individuals impact the amount of chemicals found in the environment by thinking before buying:

• Buy organically produced seeds and plants.
• Buy seeds and plants produced locally, rather than shipped across country, which requires pest-free plants, usually by heavy pesticide applications.
• Read the label. Just because a product claims to be “bee friendly” does not mean anything. Get to know the ingredients before you bring it home.
• Select plants suited to your microclimate, reducing the need for chemical interventions.
• Use integrated pest management (IPM) methods, rather than an ‘easy fix’ with long term complications.
• Tolerate a certain level of damage caused by insect pests.
• Maintain healthy soil. Healthy soil makes healthy plants that can defend themselves.

As we have learned in the past, spraying chemicals all over the place ends up causing unexpected problems. These chemicals start building up in our ground water and soil. Also, insects evolve much faster than we do. It is common for insects to develop a resistance to the poisons we spray on them, while we remain vulnerable.

Neonicotinoids may or may not be the next DDT. The truth is, we don’t know. What we do know is that there are better ways for home gardeners to care for their plants than to inundate the environment with chemicals.