I'm writing a report on different mechanisms governments or others might use to buy conservation services from farmers. That is, how they might go about paying farmers not to plant crops and instead establish grasses, legumes, or trees, or alternatively pay farmers to manage their farms in ways such that they do less environmental damage. Feel free to rant in the comment section about your views on all this. Anyway, in putting this together I stumbled upon this classic USDA report by Bowers, Rasmussen, and Baker that gives a fairly comprehensive history of agricultural support programs from 1933 through 1984. It seems agricultural policy got into the conservation business very early on. This followed not from environmental concern (no surprise there) but from the Supreme Court ruling in the case United States v. Butler et al. (297 U.S. 1, January 6, 1936). From Bowers, Rasmussen, and Baker: The Supreme Court's ruling against the production control provisions of the Agricu