For the first post of August I thought you might like to see my ideas for the Barrowwoods, home (or should I say 'haunt' ;) of the Woodspookle dragonetti.
We have quite a few tumuli dotted around the New Forest area but they are mostly found in the open, on the heath or on grassland. I've come across a few in the woods though, with trees growing on them.
I've kept the barrows above free of excessive foliage simply so that they are more visible. They seem small to us regular sized folk but to a dragonetti or the folk of the valleys they are pretty large, being diminutive folk as they are.
These tumuli, as I suspect you suspect, are a prime source of the barrowwoods' spook population.