Neonicotinoids are a popular and widely-used class of insecticides whose water-soluble nature and 20-year usage history has led to questions about their potential to accumulate in the environment and harm local ecosystems [1–6]. When first registered in the United States in 1995, these compounds promised increased efficacy, long-lasting systemic activity, lower application rates, low vertebrate toxicity, and reduced environmental persistence, all of which contributed to the rapid adoption and widespread use of this class of insecticides, which now account for over 25% of the entire global pesticide market . Over 6.7 million pounds of neonicotinoid insecticides are now applied annually on 140 different crops in the United States, with the three most popular compounds, imidacloprid (IMD), clothianidin (CLO), and thiamethoxam (TMX) making up over 90% of agricultural usage nationally [7,8].
Soil Science Extension
University of Wisconsin Madison