One oldtime beekeeper I know said that he didn't like
Roundup because of the collateral root kill damage to surrounding
trees/shrubs that he wanted. He used something called
"blue vitriol" or "Prussic acid" by dipping his machete or
a knife in the substance and cutting the bark of the tree.
He said it worked slowly but surely and got rid of undesired
trees/shrubs. Does anyone know if there are problems with
this? I'd canvass/information gather before doing it
myself.
for what it's worth- Phil Wood