Well the devil is in the details as they say. Before you get too upset consider this. With respect to any government land the rules come from 2 places. Congress, or more likely in this case by federal regulation - when a government agency makes rules pursuant to federal legislation.
I don't think far is going to succeed getting an anti yamadori bill through congress. In the event of a regulatory change every citizen can subMIT their comments to the agency making the rules. And the rules or regulations will have to spell out exactly what they mean when they say 'alpine' or coastal area...
In other words is this guy just on his soapbox or is there some vehicle for him and other like minded people to affect the change they want? If there are proposed regulations being considered, submit a comment. The agency has to play by the rules in the administrative procedure act.
And the ability of the federal government to control what you do with your private property is pretty limited. It implicates what's called the takings clause. If the govt makes rules that take away private property rights they generally have to pay you ..
I understand how federal regulations and laws work. I've covered Congress and Washington D.C. as a news reporter on regulatory issues for going on 25 years now. Regulations take many paths, some aren't as clear cut as you describe. The agency does have to play by the rules, but the rules aren't as clear cut as you assume.
If you want to see how completely tangled federal and local environmental laws about private land, just buy acreage on a coastal watershed and try to install a new septic system.. Or have an eagle nest on your property while you're trying to build your house. See how far you get with either...
What I'm saying here isn't that Mr. Farr has, or will have, direct impact on U.S. laws (and regulation would hardly be an "anti-yamadori bill," but would most likely be added on to existing federal agency rules--which is a much easier process--look what USDA did with bonsai quarantine rules), but he certainly has influence with a number of bonsai folks who are loudly vocal about stopping collection. They certainly don't fear trying to bully legal collectors into stopping or trying ruin a collector's reputation by implying that he's some kind of barbarian or even criminal.