Originally Posted by macropod

Assign a bookmark to your Grassland heading (or, at least, to Grassland itself), then insert a cross-reference to it. Copy that cross-reference to the clipboard and use Find/Replace, where:
Find = Grassland
Replace = ^c
Note: If you use Replace All, Grassland in your heading will be replaced, so you'll have to either not use that or, if you do, restore Grassland there (and perhaps the bookmark, too) after doing the Find/Replace. Again, no macros required.