WASHINGTON (AP) _ Faced with tougher and more resistant weeds, corn and soybean farmers are anxiously awaiting government decisions on a new version of a popular herbicide _ and on genetically modified seeds to grow crops designed to resist it.

Critics say more study is needed on the effects of the herbicide and they are concerned it could endanger public health.

The Environmental Protection Agency is expected to rule this fall on Dow AgroSciences' application to market Enlist. That's a new version of the 2,4-D herbicide that's been around since the 1940s.

It's partly a game of catch-up for the agriculture industry, as many farmers are dealing with weeds that have become resistant to an herbicide called glyphosate that's commonly used on corn and soybeans.