Another experiment we're doing, this one sponsored byPractical Farmers of Iowa and based on a discussion we had at the PFI cooperator's meeting, is on sweet potaotes. Sweet potatoes, like most all root vegetables, send out aboveground shoots to collect energy, which is then sent to the roots or tubers, usually in the form of starch or simpler sugars. We generally only harvest the central crown of the sweet potato plant, but because they vine across the ground, they often send ancillary roots down from their vines. These roots might help the plant get extra nutrients, and so we haven't been bothering with them, but some other farmers said that they remove these roots from the plant so that they didn't get sent any of the carbohydrates the leaves produce, with the idea that those carbohydrates would then go to the main crown, increasing the harvestable crop. So we're doing a random experiment with 10 rows, most of our crop for the year, removing the ancillary roots on half of the roots every once in a while throughout the season, then measuring how or if this affects our yields.