The term "cash crop" refers to a crop that is grown for sale rather than use. So NYT is using it correctly, but I agree they could have chosen a better term for

The term "cash crop" refers to a crop that is grown for sale rather than use. So NYT is using it correctly, but I agree they could have chosen a better term for the headline, since "cash crop" doesn't really help to explain the article. Also, to be pedantic, 3.5kg was from one American farm, not "from American farms".