I am not a fan of these super-natural art projects. It is one thing to make a statue that might stand for a thousand years ... or not. It is another to designate forest land and other resources, to attempt to lock them away from use by future generations.
The legal system dealt with this hundreds of years ago. We cannot have "dead hands" dictating how future generations should live and work. The proper vehicle for such things is government. Donate the land as a park or nature preserve and cross your fingers that your intent will be respected.
https://en.wikipedia.org/wiki/Rule_against_perpetuities
A similar worry developed around the concept of compound interest. Some semi-rich people wanted to park money in bank accounts for a few generations in order to make thier great-grandkids into powerful people... with explicit instructions on how to use that money/power. Such multi-generation shenanigans are against the general public interest.
> We cannot have "dead hands" dictating how future generations should live and work
The whole world is dictated by dead hands. I cannot walk around pristine forests (maybe I even need to pre-register), I need to deal with bureaucracy, I need to pay taxes, almost every single landscape is ruined by human buildings, etc. So what is that even about?
It's 88 years. The odds of it falling afoul of the law against perpetuities is negligible and would indicate something catastrophic happened.