Just cut the weed trees down and check by a few times the following summers to remove any suckers from the stumps.

I agree with huggorm. I get pecan trees too as my neighbor across the street has a huge pecan tree. I suspect that the squirrel population takes and buries some of the pecans in my yard as I am across the street. If they are tiny, under 12 inches, I pull them up, if they are hiding in foliage and have gotten a bit bigger I cut them off at ground level.

And don't follow the advice you're bound to receive about painting the cut stems with herbicide. Someone will certainly suggest it soon.

Systemic herbicides are known to pass their properties from plant to plant via the underground root system (rhizosphere).

Follow the most excellent advice you've received about pulling and cutting.

Thanks for the advice!! No herbicides!

I have used huggorm's method before successfully.

This very much strikes me as one of those situations where anybody who doesn't like my use of herbicides is more than welcome to come and pull and cut (and cut, and cut, and cut) my weed trees. I have maple saplings I've cut 3 or 4 times without killing them because I was too lazy to walk back to the garage for the herbicide. Those things don't die.

I use them too, Mads...and often in a carrier such as paraffin (kerosene?). Elder, Buddleja and woody shrubs such as bramble would be utterly impossible to control in my woodlands without the use of herbicides. I either dress the fresh cut (must be treated immediately a cut is made) or I have drilled into the top surface on older stumps or even into the vascular system just beneath the cambium. Not with glyphosate though, which I have always applied through the foliage.

I'm totally against herbicides,on principal. The D##NED things are apparently working their way into food crops by now,and there just is no need for them. My woodland /wild "garden" is full of some of the worst plant thugs known to man: brambles, vitalba, ginestra (broom)...in comparison to these ,the weedy trees are like petunias , lol. All you have to do is cut them level with soil and cover the offenders with cardboard,and put mulch on top of it. If it's really bad, use several layers of cardboard. If it's really, really bad,use black plastic. Roses are extremely sensitive to herbicides, but in any case, these things-herbicides- are poisons,and we don't want to be spreading about more poison in our world,now, do we? No, we don't.

I agree, bart.

Sometimes I think that people treat poisons as though they aren't poisonous.