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... Read More Trends in corn herbicide use (1990 to 2014) By Andrew Kniss (Independent Expert) on Friday, June 26, 2015 - 11:07 Category: Impact on Environment, Impact on Farms Share Originally posted at Weed Control Freaks.