There is a superb technique for trees that someone discovered on Cartotalk that involves a monochromatic noise filter and a bevel. It wouldn't match the scale of this grass, but it would be good for regional to wide local maps. I used the technique on the Mennin's Hallow map to good effect.

Here's the thread I found it in: http://www.cartographersguild.com/showthread.php?t=1139