June 12, 1914] 



SCIENCE 



859 



Forest, N. C., and now adopted by tBe Federal 

 Department of Agriculture. It is a great im- 

 provement over any terracing to be found 

 in either Europe or America. It consists of 

 wide gentle ridges plowed up along the face of 

 the slope so that the water flows slowly and 

 harmlessly along it, while its wide gentle slope 

 permits the planting of crops and the utiliza- 

 tion of agricultural machinery directly across 

 it at the same time that it controls the run- 

 away waters. There is almost no washing of 

 earth where the system is maintained, and the 

 ground is fully utilized in the American way. 



A proper appreciation of the economic 

 and far-reaching importance of soil saving 

 should bring us in a short time to a point 

 where, by compulsion or premium, all tilled 

 lands liable to washing would be handled by 

 this method or some other equally efficient one. 



4. Plowless utilization of land offers great 

 possibilities for the checking of erosion and 

 the vast increase of our crop area. 



(a) Forestry and Pasture. — Thus far tree 

 planting in the form of forestry has been 

 almost the sole panacea, other than pasture, 

 for steep lands. The fruitlessness and slow- 

 ness of a forest, which yields its one crop in 

 from twenty to one hundred and fifty years, 

 is a profound objection to it as a resource for 

 the owner of the average small farm. The 

 yield of hill pastures is too small to be a 

 satisfactory dependence. Therefore, we have 

 plowed, gullied and destroyed. 



The inefficiency of pasture is indicated by 

 its almost entire elimination in the arable 

 areas of western Europe where it has given 

 away to tilled crops. Its inefficiency in com- 

 parison to tree crops is shown by the fact that 

 the pounds of food, the income and the nutri- 

 tion produced by an acre of good sheep pasture 

 in England are less than that produced by a 

 good walnut tree in France. 



(&) Crop Trees. — The tree is nature's real 

 engine of production. This scientific fact 

 seems to have been overlooked, despite the 

 great value that trees have been to us. By a 

 spasmodic and chance development, the tree 

 has given us a number of valuable tree crops. 

 The land that is in harvest-yielding trees is 



usually the heaviest yielding and most valu- 

 able land. Witness the orchards everywhere. 

 The king of all crops, as measured by the 

 greatest amount of food produced and the 

 value of the land, is a tree crop — the date. 



Past development of tree crops has come 

 peculiarly by chance. Now that we know how 

 to breed plants, we need the systematic exam- 

 ination of all the trees of the country with 

 regard to their present or potential crop pos- 

 sibilities. This is a task requiring much work 

 and having tremendous promise of increased 

 national wealth. This conclusion is borne out 

 by the facts now known concerning American 

 trees, and by the occasional development of 

 tree agriculture both in this country and in 

 Europe. 



In this country while we have an extensive 

 fruit industry, it has touched but a small 

 corner of the possible tree-crop field, and the 

 crops have been limited chiefly to those fruits 

 that may be classed as succulents rather than 

 nutrients, and they have been limited also to- 

 human food rather than to forage. Forage is 

 the great demand upon the American farm. 

 The animals eat several times as much as 

 we do. 



1. Tree Forage. — Forage tree crops in Eu- 

 rope, Africa and Hawaii, are suggestive of 

 great developments in America. The carob 

 bean, worth about one cent per pound at the 

 farm, is a much prized nitrogenous and also 

 carbohydrate stock food widely grown from 

 Gibraltar to Palestine, and exported to Eng- 

 land and to some extent to the United States. 

 In Hawaii we have its counterpart, the mes- 

 quite bean, a bran and cornmeal substitute, 

 rapidly becoming an important industry. The 

 yields reported by the Hawaiian Experiment 

 Station are almost staggering in their signifi- 

 cance. Mesquite forests on rough untilled and 

 untillable land are producing from 4 to 10 

 tons of beans per acre and the bean meal sells 

 at $25 a ton. We have in the United States, 

 waiting to be developed, similar leguminous, 

 cropping trees growing from the Pacific to the 

 Atlantic in the form of the mesquite in the 

 west and the honey locust in the east, both 

 great bean-yielding trees. 



