Australian M816 wrecker build.

[Ron King]

Australian Army during the 1980s used a hold fast system which was a cast steel frame with about 8 holes for ground pins to be hammered though.
Early pins were round and later pins were hexagonal as the hex pins when twisted round a bit were easier to remove.
The cast frame had a big D shackel which could join it to other holdfasts in line to increase anchoring force..
I don't remember any special anchoring gear just for the 816 as it's 20 tons weight with hydraulic micro switch brake lock on was usually enough for most jobs.
On the East coast of Australia where I did use the 816 plenty of trees are around.
Heavy winching done out the back with the front winch for self recovery and if necessary out to a tree or another anchor point.