Any rights without a lease? Living 35 years in Los Angeles rent control apt with no lease. Did not ask permission but nothing said 25 years ago when I put up trellis with a screen door on porch area for plants and privacy due to a driveway a few feet away. Landlord suddenly wants it removed.

He owns the property... he makes that decision. Doesn't matter how long its been there if you put it there. It doesn't matter if you had a written lease or not.

If he has seen it, and was OK with it before you have some room for discussion. Have you asked them why they want it down ? Is it the same landlord ?

But they can order remodeling, and how the house is to be fixed up. I will say, is this a 25 year improvement, how does it look now ? Perhaps they are concerned or have complaints on how it looks.

Now that the legal question has been answered:

What if he had objected 25 years ago? You'd still be out time and money. You've enjoyed them for all these years, and although it might be pleasant for your privacy, is it possible that they are getting sort of decrepit? Perhaps there is some nice way you can find out what he doesn't like, and might like better.