Wild Rose Invasion
The neighbor's roses have invaded from under the fence into our lilac bush. There is 3'-4' of empty space where both lilac and wild rose suckers have grown. If I leave them alone will the wild roses kill or strangle the lilacs? How do i get rid of them without killing the main lilac bush (the roots are intertwined) or spreading the roses further into yard?
The rose plants won't kill the lilacs.
It may be possible to eliminate the roses by cutting them off and applying an herbicide to the cut stubs. However, this might harm your neighbor's rose plants because their roots are probably connected to those growing under the lilac. Severing all the roots on the neighbor's side of the fence before applying an herbicide would reduce the risk but the solution would only be temporary unless a root barrier of some kind was installed at the same time.
Cutting off the rose suckers frequently will suppress but not eliminate them.