well I see your point Trout, but the tenant doesn’t own anything in the eyes of the law.
Trespassing I can agree with, but I see it as a responsibility to report to landlord and not a lot else.
Has your daughter spoken to to landlord yet? there might be a slim chance it was pre-agreed? They may have verbal agreements regarding upkeep of plants/grounds etc.
The most simple thing to do would be take a deep breath, knock on the door and say something like ”sorry but I cant help but notice you have entered my garden and cut down a hedge, did you have permission to do so?”
If they say yes, they verify.
If they say no, then ask what was their reason for trespassing, and I will have to report this.
That or speak to the landlord first.
Keep the moral high ground. For now, at least.