EnumPlantType is designed to be added to at runtime, which will lead to ArrayIndexOutOfBoundsExceptions when using a switch() statement on it.

Offending code:

https://github.com/Glitchfiend/BiomesOPlenty/blob/BOP-1.9.4-4.1.x/src/main/java/biomesoplenty/common/block/BlockBOPGrass.java#L143

(maybe more)

some crash logs: SleepyTrousers/EnderIO-1.5-1.12#3501

@HenryLoenwind BoP haven't actively been worked on for quite a while - although PRs do still get checked. Since you understand what the problem is and know how to fix it, you could perhaps do a PR for it ? :)