Legumes, of which there are many species, can be grown between nut-yielding trees to maintain the fertility of the soil through the nitrogen gathering nodules upon their roots. As it often seems desirable to cultivate trees of this character where possible, the tree crops agriculturist is above all others able to adjust his crop and the one device that permits the tillage of hilly land--terracing. Terraces interfere with machinery which is so increasingly essential in the cultivation and harvesting of the present crops. But terracing interferes least of all with the tree crop agriculture, because the trees can stand in the terrace rows and make a fortunate combination of the heavy yielding tree crops and the soil preservation through terracing. We have an interesting example of tree crop productivity in Hawaii, where the agaroba was introduced from Peru in the last century. It has now spread until it covers considerable area with forests, and information from the Hawaiian Experiment Station is to the effect that it is now the mainstay of the dairy industry of the island. The annual crop of four tons of big beans to the acre can be and is ground into a highly nutritious meal food selling at $25 a ton, an agriculture which, for ease of operation and richness of return, puts Illinois to shame, for, in addition to the $100 worth of animal food, there is a ton of wood per acre every year. The tree crop agriculture seems to hold the possibility of letting the worst third of our soil (Class 1 as mentioned above) become as productive as the best land (Class 3), while (Class 2) the hill land can probably be doubled in productivity. This is a goal well worthy of much endeavor on the part of the plant breeder.