Grass foliage bug?

Hello everyone! I’m trying to make grass for my landscape but it always changes color when I move away. As you can see in the print, in longer distance, grass becomes light brown. I’m sure about two things:

1_ Is not the materal. I tried a lot of materials and differents BP.
2_ Is not the mesh. I make two mesh in Maya and others two in Blender, always with different settings, and always the same bug.

Things about my grass:
Currently mesh was builded in Maya; I get the material from KiteDemo Project;

I don’t think it’s about light and i don’t know if it’s about importing settings or something like that… Can someone help me to fix this?

Right, there’s the result:

We have here 3 materials, cause my grass have 3 different planes in his mesh.