I saw this on Facebook today, and I was torn. On the one hand, I believe that I understood the sentiment behind the question, but on the other hand I recognized immediately that the question - posed with those photos and captions - is a factually meaningless question, since it conflates disparate meanings of what is the United States, confuses (il)legality with regulation, and uses a troubling definition of "nature" as its counterpoint to the questioning of the purported illegality of the four photos.
While the photo is technically true, it is only so if you make all the mistakes listed above. So I'm going to go through them one at a time.
Collecting rain water is illegal by state law in a some states in the Western US that operate on the prior-appropriation doctrine of water law. It's a stupid precedent, but it's not at all something that is banned in almost the entirety of the US. Indeed, in the US Virgin Islands, new construction is required to have rainwater harvesting systems, and - since the US Virgin Islands are a territory of the US - this requirement is more akin to a federal law than any of the laws banning rainwater collection.
Cannabis is the inverse of rainwater collection: it's banned by federal law, but not by some state laws. This is working its way through state legislatures, both as a hemp-legalization law as well as a marijuana-legalization law. But this one I'll give you as the "banned in the U.S.A." moniker.
Raw milk is banned by the FDA in interstate trade (which is the only way that the federal government can regulate a commodity), and so - again - I'll give you the "banned in the U.S.A." moniker, but - again - it's not so simple. State and local laws actually do allow the sale of raw milk in stores, but (at least in the State of Michigan, where I live) there are laws about how that milk is stored and sold. I seem to recall, too, that other states do allow direct sale of raw milk from the farmer to consumers. So, technically banned, but in reality legal in many places.
Unlicensed inland fishing is illegal under individual state laws, and - as far as I know - all 50 states require licenses to fish. This is technically not "banned in the U.S.A." under federal law, but is effectively "banned in the U.S.A." under state law, so it's a wash. As far as I know, the only federal laws about inland fishing bans regard endangered species, which are not what most people are fishing for. Now open ocean fishing requires licensing with the federal government, but that's not what this boy's doing, nor is it what most Americans do when they do fishing. Still, on open ocean fishing, the moniker "Banned in the U.S.A." is appropriate.
Finally, though, there is the tag line, "When did nature become illegal?" There are many points here that are interesting. As I showed above, none of these are always illegal, which means that they can all be regulated activities, which is different than an illegal activity. Changing the tag line to the more accurate, "When did nature become regulated?" actually does let you think about the history of human interaction with the land/air/water of the territory that would become the United States of America. If we presume a common cultural heritage that goes back to the Jamestown colony (and not Spanish colonization), then the answer to the question, "When did nature become regulated?" goes back to the Jamestown Charter of 1606.
However, even then, we are left with the other epidemiologically troubling word: "nature." I'm not going to even conjecture about the concept of "nature" in 1606 (although there are many books about it, including Death of Nature by Carolyn Merchant), but focus on the present day in the United States. The idea of "nature" usually is independent of the idea of "utility," and going by that tendency, only cannabis is actually "nature," since all the others are presented either explicitly in terms of utility (collecting rainwater, unlicensed fishing) or implicitly in terms of social utility (milk as we use it in society - raw or not - is a commodity and not a natural product). Indeed, even cannabis - if grown for the purpose of medical or industrial use - will no longer be of "nature" either, but another commodity, like milk. And this definition of "nature" is not even one that discusses nature as an interconnected relationship between organisms; the ecological perspective of nature (of which there are many books written as well).
In sum, the picture is technically correct in a very narrow reading of the terms, "nature," "illegal," and "U.S.A." Changing "illegal" to "regulated," recognizing the federalist structure of U.S. government, and - further - being very generous with the definition of "nature," the short answer is, "In 1606." The specific dates for the individual points, though, are - I'm sure - available if you search for them.