Hey,
Everything in the content pictures is included. This means also the 'grass-texture'.
This isn't a tile as you would know it for instance from rpg-makers.
It's more like parallax mapping techniques. I had applied a few adjustments and I've painted a way over the grass texture.
You can either use Photoshop, Gimp or Krita (last both are freeware). Or whatever you want.
This set doesn't include any other complex ground textures or ground tiles. Hence everyone has to create his own individual ground textures.