If you have some experience with compositing in a paint program you can render this pic with and without AA and composite the unAAed grass into the AAed pic. If you have a version of Photoshop, copy and paste the AAed version on top of the unAAed version. Then, using the magic wand tool, pick the grass on the AAed version. Be sure you select "antialiased" and "contiguous" and deselect "use all layers". If the wand picks parts of the pic besides grass, undo and lower the Tolerance number and try again. When you are happy with the area chosen by the magic wand, select the "Clear" choice in the Edit pull-down menu. Now the unAAed grass should show through the selected area. Just repeat for each grassy area. Also, if you'd like to mix the two rendered grasses a little, you can paste the original AAed pic on top of the new pic you've made and use the layer transparency slider on the second AAed pic until the two are mixed in a proportion you like. Hope this helps.

This is not my "second childhood". I'm not finished with the first one yet.

Time flies like an arrow; fruit flies like a banana.

"I'd like to die peacefully in my sleep like my grandfather....not screaming in terror like the passengers on his bus." - Jack Handy