I've been planting them for about 3-4 years. Deer love the tops, and will eat the tubers too. They are great for breaking up hardpan. In the spring, when they rot, they'll feed your soil. No frost needed for the deer to eat them, like PTT. The tops grow more up, than out, therefore making for a better companion crop, than rape. Rape spreads outward and when planted too thick, can shade out other plantings.