The rendered "short grass" that appears on grass blocks should disappear if another block is placed on top of the grass block. While this is a nonissue for solid blocks that keep you from seeing the short grass inside as well as degrading the grass to dirt, it is an issue with transparent blocks and tile entities that allow the grass to stay grass, and still show the short grass rendering through the transparent portions of the block.

This is especially apparent with machine blocks from mods that have large transparent sections like the squeezer from Integrated Dynamics, energy cells from Thermal Exp, shetiphian ender chests, any tanks, as well as any kind of glass.