Do property owners own land right up to the border or is there some sort of buffer?
No...
I know a family NW of Big Bend that owns land right up to the river...
Now if there is a “buffer” zone, I have not really heard about it...It would be kinda like an “easement” of sorts...I have one on two sides of my property here, that I have to maintain (mow, edge etc etc) one is a pipeline or utility easement, and the other is a “right of way” raod easement...
The answer is both. As far as I know in most places property owners own the land right to the border. There is a strip here in NM that is a government right of way that was originally set up to protect the border (might have been part of the issue of contagious cattle disease many years ago) this strip is controlled by the Dept. of Interior and they have delegated the authority to the BLM. Interesting thing is that a few months ago the BLM would not allow the Border Patrol to make a road right on the border- due to their concern about the environmental damage. Insanity rules when it comes to the border- so many, including our own government see no need to secure the border. It simply amazes me.
Do property owners own land right up to the border or is there some sort of buffer?
Texas is somewhat unique in land ownership in that the Feds basically owned no land in Texas when Texas entered the Union. The land was owned by the state or individuals up to the border, etc. Since then of course the Feds have purchased or acquired land in Texas. But a lot of the land along the border is still private or state/county/city owned up to the border line on the US side.