Yes, he is the owner of the bushes (fruits or no fruits). But the neighbor is a disturber of the adjacent property by planting the plants and is obliged to remove the property disturbance, meaning he must remove the shrubs at his own expense. Giving him time until the end of April to commission a company and to carry out the removal seems appropriate to me. It is not even mid-February. Deadline until 10.04.2015 and - in case of non-compliance - extension until 30.04.2015, after which he will be in default. With both deadlines, the option of self-removal for the futile expiration of the deadlines should already be threatened.
Actually quite simple, if it weren’t for the interpersonal component. The aforementioned measures are the "emergency measure" which should only be applied if the friendly visit including introduction of the persons and the plans does not fall on fertile ground. I would like to point out briefly that not all future neighbors are open to friendly arguments. The digging of the long trench here actually already speaks volumes, at least there is a certain tension in the air. The neighbor could have come to the conclusion himself after staking out the property that certain talks are pending. To spice that up with additional measures on foreign ground ... is rather cheeky.
I am very curious about the outcome of the conversation. Apparently he is not popular, otherwise the other neighbor would not have immediately thrown him under the bus "... knew that exactly ...". That is also rather not a good sign, but it can be helpful, because then not the entire neighborhood takes a harder line against you, but they (possibly secretly) enjoy that someone is finally putting him in his place. But that is all crystal ball reading, it could also be quite different.
Toitoitoi, it really starts out rough. All thumbs are heavily crossed here for an amicable solution.