Any time you put a tree sapling in your hand, all textures excluding water turns black.

Any time I start a Minecraft world and begin chopping down trees, I'll get a tree sapling and then all my textures go black, except for water.

Steps to Reproduce:
1. Start a Minecraft game on 1.7.2
2. Begin chopping down trees until saplings start spawning
3. Pick one up and watch what happens.