If it’s her property I would tell them to stay off.The property is private.So don’t trespass.
If she is leasing the property from the government she can do nothing.Afterall they’re the property owners.
And, this is the official site for the survey in question:
https://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/technical/nra/ceap/na/?cid=nrcs143_014159
Their ‘affiliates’ include (dun dun dun):
“State of the Nation’s Ecosystems offsite link image by The Heinz Center is an important effort to develop indicators for ecological values of what they call grasslands and shrublands.”