@ calico, I don't believe the thread you have put up is the one, because I have the tgds' for the "strata" instruction and they do not look any thing like the scenery that I sent in the "dirt" tgd yesterday.
@ HW, You will need to go into top view mode (in addition to the preview window) and get a white painted shader mask made of the foreground area, and make that mask *.jpg (with a re established name) available to your render via the same folder as the tgd I sent resides in. Make the area of your mask to your own set of coordinates, location and size,
and then you should be able to work on gaining the tilled look (possibly with vornoi) that you said you want. I am kind of adding this instruction on getting another mask made assuming the least amount of experience with painted shader masks, so if I am preaching to the choir please disregard. Good luck and let us know how your endeavor goes.