Andrew Kniss is an Associate Professor of Weed Ecology & Management in the Department of Plant Sciences at the University of Wyoming. He has a PhD in Agronomy with a minor in Statistics. Andrew's research program focuses on developing weed management programs in agronomic crops, especially...
Trends in corn herbicide use (1990 to 2014)
Originally posted at Weed Control Freaks.
USDA-NASS recently published the most recent corn herbicide use data (from 2014). I’ve been looking through the data, because, well, free data! Perhaps the figure below isn’t the ideal way to present it, but there are some interesting trends that can be observed this way. Total herbicide use in corn (in weight of herbicide applied) has remained relatively constant at about 2 to 2.5 lbs/acre since around 2000 (Top panel A). There have certainly been changes in which herbicides contributed to that total, though. Alachlor and cyanazine use has stopped due to health and environmental concerns. Butylate and bromoxynil declined; an argument could certainly be made that this was due to farmers switching to glyphosate in Roundup Ready crops. Metolachlor and dimethenamid also declined in weight applied, but this seems mostly due to newer formulations with lower use rates (S-metolachlor and dimethenamid-P).