I'd say to semi-limit it to home or hobby-business stuff. A guy who has a few bee hives or a few fruit trees to sell stuff at a farmers market would qualify but not a full blown business. Most of us aren't farmers. We're hobbyists.
At the same time, info about pesticides or irrigation on a large scale is also applicable to hobby farming so that needs to be considered.
Really?
Then I would certainly not contribute, with that sort of regulation on a forum.
By the same line of thinking, we should also prohibit someone that makes their living in the firearms industry from posting in the shooting forums.
Here's a clue for you...
People that want advice on how certain things work, and why they work that way, are not going to seek that advice from other beginners. The input of people that actually know the mechanics of a specialized subject are the most valuable part of the discussions.
