So, I have dirt roads I made with Pandora's Box but I can't figure out how to
do the blending border with the grass? See the pic below:

upload_2017-10-17_4-54-7.png
 
There are grass edge pieces(edges)- you won't see them though unless you add them on top of the dirt, which case you will need to raise them by 1 so these don't sink into the dirt. Or check the dirt pieces- there should be dirt edges also these are just lighter and they could be added on the edge of the (outside) of the dirt.
 
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