I have 2 mature trees in my backyard - a lilac and an american holly. They have grown close together in the center and form a wonderful canopy of shade where I can sit in the summer. I am concerned that the lilac is not getting any sun exposure where it adjoins with the Holly as there is alot of dead wood. In general, I think the Holly is squeezing out the lilac. Do I need to prune back both trees to eliminate my shade canopy or will the lilac adjust. The lilac is about 60 years old and has alot of lichen on its trunk and branches.
American holly is quite rare in gardens here. You are much more likely to have the very common and pestiferous* English holly. If that is the case you could cut the holly down and give the lilac the full exposure it enjoys. Otherwise, the holly can be cut way back, away from the lilac and will not be bothered by such treatment. *A serious nuisance in local parks and other wooded places
