Marestail (or horseweed) is growing rapidly this spring across much of the state. Be sure you are scouting your no-till soybean fields this spring and early summer and selecting appropriate control measures. Before you plant soybeans or corn, consider overall marestail management. Extension weed specialist Dwight Lingenfelter tells us this weed is mostly a problem in no-till and more of a problem in soybean than corn. It is also common along the margins of some fields where herbicide programs are usually more hit or miss. Much of the marestail in the region is glyphosate resistant, and pockets of Group 2 or ALS-inhibitor (Classic, FirstRate, etc.) resistant biotypes also exist.