First of all, Welcome to the forum

I looked into using the USDA 'organic' label and what I found is that there is a huge amount of paperwork involved, licenses, permits, inspections (you have to pay extra for them), and that at any time, the inspectors can demand to perform surprise inspections of your premises (which would cost you more money, and put more into their pockets). If I was to find that using the word 'organic' was illegal without having their permission to do so, I would just use 'naturally raised' or some other such term to avoid all of the permits/licenses/inspections! To spend all that money, keep all those records, put up with all those inspections, and pay for licenses, inspections, and permits would be too cost prohibitive just to sell a few fish/veggies at the farmer's market!