Roundup Ready® soybeans are used on more than 60% of Iowa’s soybean acreage. Insertion of gene coding for an insensitive target site allows the application of glyphosate (Roundup®) to these soybeans. The rapid adoption of this technology is due largely to the high level of effectiveness of glyphosate and the simplicity of the management system. In recent years numerous manufacturers have introduced herbicides containing glyphosate that compete directly with the Roundup® brands sold by Monsanto. A common question is whether the ‘generic’ brands of glyphosate perform similarly to products offered by Monsanto, specifically Roundup UltraMax®. The objective of this experiment was to compare three brands of glyphosate for weed management in Roundup Ready® soybeans.