I don't know how, but tiny maple trees spring up in my yard. (We have maples in the yard) I try and pull up as many as possible as soon as I see them, but some of the roots are so stubborn I can't pull them. Also my neighbors have let several of these trees grow to two feet tall between our fences. How can I kill these things? Without hurting other vegetation? Do I have to dig the root up with a spade or shovel?? I really need help with this problem. Thanks Helen Ag