Crab Grass

Crab grass would be a faster growing and dark green variant of a grass block, which can be found and collected naturally with a silk touch tool, or crafted with a grass block and bonemeal in a crafting grid. Besides the color of the block, the main difference between crab grass and grass is that crab grass is taller, and looks like it has shrubs on top. 

Since crab grass grows back faster and taller than normal grass, it is often a sheep’s favorite block to eat.