I would hit them with Tordon if you want to kill them ..
that is my plan with the garlon 4. I was just hoping it would still be effective in January. I'll have to look at the label.If you want to chemically kill a tree use Garlon 4 and bark oil. It does not translocate and is very potent to whatever you are trying to kill.
I've used garlon4 in Minnesota when the temperature has been below zero. It has worked although I haven't looked at the label to see if there is a recommended temperature.that is my plan with the garlon 4. I was just hoping it would still be effective in January. I'll have to look at the label.
Thanks for the responses
Be careful with Tordon, it will translocate through underground, cross connected roots and could kill adjacent, desirable trees while you are targeting undesirable species. Tordon will kill the fire out of whatever you apply it to, but just make sure your targeted tree is not too close to other, desirable trees.
Thanks for the heads up Daver ...