Probably the best way would be making it self-documenting: installing some sort of plaque or stand describing it and why it is scientifically interesting. Then any work crews sent out to destroy it can see the plaque and exercise some discretion in sending it up channels to ask.
Once upon a time my father discovered that the right of way along the road beside our property had several species of somewhat rare semi-protected carnivores plants growing in it. My dad contacted the county about it, they made a note of it, The mowing crew mowed over it the next day. He replanted the area with plants and seeds from his own collection, and the county put up "Do Not Mow, protected plant sanctuary" signs in the middle of the right of way. The mowing crew's solution...take down the signs so they could mow, and then put them back up when they were done.