I drill holes in the base material and stick in the grass with a drop of glue on the bottom. There will be a lot more going in, so this is just a start right now.
As for the Mod Podge, I was hoping to get the water about halfway up the roadwheels on the M-56 Scorpion. The Mod Podge is the third water product I've tried. It's really frustrating because you read about everyone's techniques for making water on here, and each is different, but I can't afford to go out and buy ten different products at once to see which one is best. Not to mention with two kids, hobby time is at a premium. So I guess I'll start looking for some Envirotex next then.
Hans, do you mean shorter tufts of this stuff first (the same stuff I'm using), or lay down a base of some of the crumbly grass products?
Thanks all for your tips so far!