[diesel_john]

imo because of the seed technology we have now vs. the last time natural was tried on a large scale, the industry on average could probably sustain yields in the 50 % range of what they are now. Rotation is used in some form in most operations. Fallow is used where only one crop can be grown and natural emeny have made that crop uneconomical. But rotation is still used because the natural enemies can adapt to repetitious practices.