Battling Buckthorn

Buckthorn is a tricky enemy.  I pull buckthorn and I cut buckthorn and poison the stem with Brush B Gone.  Some of those I pulled earlier this summer, three feet high. sit there on their exposed roots still growing?!   What!   I pull more buckthorn even though my hamstrings sing in protest.  Those I do pull are relocated to the branches of a crab apple or a black walnut tree so their evil roots can not reach the ground.  I hope the rain and the snow expose those buckthorn roots and kill them dead.  Some I pull but can not pull out.  My hamstrings complain loudly.  I cut their stem and poison them.  Some places the buckthorn are so thick it's easier to proceed on my hands and knees.  Dang. Today I killed at least 100 buckthorn and did not kill them all.  The trickiest buckthorn trees are the ones that look like I could maybe pull them out so I try but I can't so then I have to bend over and cut them.  Areas that have been cut previously are the worst.  When I cut the stem and spray the poison goes down an inch or so.  Some of these trees, after a year or so of being poisoned, send out new branches sideways for 10 inches and then go vertical.  Even though they're short they're impossible to pull out.  My idea was to kill buckthorn and also identify who is a rooster and who is a hen among my Polish chickens.  No chickens crowed while I was out there.  I worked steady and furiously until my hips said, "Enough!"  As a homeowner I have learned there will always be more work for tomorrow!