Since the trees were on his property and he is not allowed to physically prevent you from using the easement, it is perfectly clear that he must remove all objects blocking your use of the easement. With an easement, the person granting the easement still owns the property, they are merely allowing someone else to use the property without being a trespasser. Since he refuses to pay, send him the bill for the work you did in removing the tree from your property and the easement. A very common example is as to your own home. You own the property from the rear property line to half way into the deeded in street [which often in not the actual middle of the covered street], but you are required to give the local entity the right to use an easement across the front of your property to build and maintain both the street and sidewalk.
Answered on Mar 03rd, 2016 at 3:44 AM