Why use a soybean residual?

Published on: 14:39PM Jan 04, 2011

Gordon Vail

At harvest, growers saw a few leftover "surprises" in their fields, especially in soybeans that relied on “economical” total-post glyphosate herbicide programs. Many weeds – like waterhemp and giant ragweed – thrived throughout the season, creating a seed bank that will need to be managed next season and beyond.
It makes sense to use a strong residual program for your soybean crop. Research by Bryan Young from Southern Illinois University has shown that a pre-emergence herbicide followed by glyphosate will out-yield two properly timed post applications of glyphosate by 3 bu/A, when glyphosate was applied to weeds
So, if soybeans are at $12 to $13/bu (or more), you can do the math: Using a soybean residual herbicide could return nearly $40/A more in gross profit than two applications of glyphosate. The yield advantage of the residual followed by glyphosate program increased to 6 bu/A when glyphosate was applied to weeds up to 8” tall, which is certainly not uncommon.  Just something to think about as 2011 plans are in the works.

Gordon Vail, Syngenta Herbicide Technical Brand Manager, provides technical leadership for the biological development and labeling of corn herbicides for Syngenta. He holds a bachelor's degree in agronomy and a master's degree in weed science from the University of Arkansas, as well as a doctorate in botany and plant pathology from Purdue University.