Another thing you could try is to eliminate so many distance textures per crop. All you really need is a green, brown, and dead distance texture. Also, for certain "flowering" stages of certain crops (like yellow for canola, etc). The distance layers are all optional, so you can make them whatever you want.
At 3-4 textures per crop, you could have 60 - 70 crops on the map which is double what a vanilla map supports. It must be making a texture array for reused texture files to only count as 1. I'm still waiting to hear back from a couple people, but it's not an issue many have run into. In fact, you're the first that's ever mentioned it to me.