Re: help needed; russian olive trees and berries and ir horse
You might look into electric fencing. If it's a small area, you could put some up pretty inexpensively. They run on solar and you can also use backup batteries. It's a very temporary fix, and won't make any impact on the environment of the area you use it.
Joy and Willie (PPID/IR)
Nevada County, CA - 2019
Case history: https://ecir.groups.io/g/CaseHistory/files/Joy%20and%20Willie
Willie's photo album: https://ecir.groups.io/g/CaseHistory/album?id=242526