No-tillage conditions result in greater diversity in the weed species and weed life cycles that occur in corn and soybean production, compared with conventional and minimum tillage systems. This diversity can be challenging to manage, especially when growers attempt to oversimplify herbicide programs in hopes of cutting costs. Successfully managing weeds in no-till can be accomplished with relatively minor changes in herbicide programs, or it can require a substantial change in strategy, depending upon the nature of the weed population. Failure to use the appropriate strategy, or to adapt new strategies in response to weed population shifts, can result in poor weed control and further increases in populations. For example, some Roundup Ready soybean growers in Ohio have omitted preplant burndown treatments from their weed management programs, which have resulted in increased populations of winter annual weeds and dandelions, and problems with control of early-emerging summer annual weeds such as lambsquarters and giant ragweed. This approach has also contributed to over-reliance on glyphosate, and has been a primary cause of glyphosate resistance in horseweed (marestail).