Grass sprites broken

http://cloud-2.steampowered.com/ugc/595883498798666365/EFAE00E313A0B3D555220DAFAAF3B785F859EE20/

All of my grass looks like this. What’s causing it, and how can I fix it?

-snip-

Look at them, they’re all cut up, the wrong ones, in the ground, floating, you name it.

Mow it.

Delete the custom detailsprites in “materials/detail”, look through all the game directories if you’re unsure where it is.