Genetically Modified Organisms

Being a redneck, I am not as informed as might be necessary to carry out a logical conversation/debate on the implementation of GMO's. But it seems to me that the arguments against them, especially those from the environmentalist side, are unfounded and ignorant. It seems to me that, from their prospective, that the implementation of GMO's would reduce the impact of agriculture on the environment. GMO's yield more product per acre than their traditional counterparts. So less land would be needed for farming. Less land needed for farming means less land is deforested, which is a goal that I believed environmentalists wanted. If I wrong, or sadly misinformed, please inform me.