I have to say I too would object strongly if my neighbour wanted to plant those aspens on that narrow strip. The trees are beautiful per se but totally unsuited to that situation. They are far too big. They are also relatively short lived and the roots will spread through both your yards.
Even arborvitae spread more than that narrow strip.
OP - whatever you plant should be wholly contained within your property. Your neighbors can remove anything that hangs over onto their property. Virtually anything you plant there will encroach on their property. Those aspens have a spread of at least 6' and up to 10'. That's not even considering what the roots might do to the driveway. You don't have room for that. Period.
Honestly, your neighbors don't sound unfriendly to me - they sound realistic.
I have to say I too would object strongly if my neighbour wanted to plant those aspens on that narrow strip. The trees are beautiful per se but totally unsuited to that situation. They are far too big. They are also relatively short lived and the roots will spread through both your yards.
Even arborvitae spread more than that narrow strip.
OP - whatever you plant should be wholly contained within your property. Your neighbors can remove anything that hangs over onto their property. Virtually anything you plant there will encroach on their property. Those aspens have a spread of at least 6' and up to 10'. That's not even considering what the roots might do to the driveway. You don't have room for that. Period.
Honestly, your neighbors don't sound unfriendly to me - they sound realistic.