FOREST LANDS FOB THE PROTECTION OF WATERSHEDS. 19 



you purchase the lower slopes or the upper slopes of the mountain ? 

 And I want your scientific opinion. 



Doctor VAN HISE. I shall give you my best judgment of the mat- 

 ter. My principle of action would be this : Upon the whole, from the 

 point of view of the nation, is this land more valuable to the nation 

 for agricultural purposes or for the purposes of forestry and the 

 regulating of the sCTlams? If, upon the whole, that land, using the 

 best data and judgment, if the slopes were such, the soils were such, 

 the conditions were such that the land could be used for a reason- 

 able length of time, with care practically perpetually, for agricul- 

 tural purposes, certainly it should be used for agricultural purposes. 

 But if the slopes are so steep that that is not practicable; if the 

 slopes are so steep that it is not economical to do that; if the slopes 

 are so steep, as in the Balsams, for instance, where the land will be 

 gone in five years, that never should have been allowed to become an 

 agricultural tract, and if under those circumstances that land has 

 become an agricultural tract, it should be reconverted into a forest 

 tract. 



The CHAIRMAN. Governor Guild, let me say aside, you will pardon 

 me for taking this time with Mr. Van Hise, but it is because we know 

 he is an expert on this question, and I think we can get some informa- 

 tion, and I am sure the committee will extend the time. 



Governor GUILD. Certainly, Mr. Chairman. 



The CHAIRMAN. Now, Doctor, leaving out of account the question 

 of the rights or the necessity of the people to live in North Carolina, 

 as a scientific proposition, if you were commissioned to buy the land 

 and had to take your choice between the lower third and the upper 

 two-thirds of the* ranges, and your only purpose in buying it was to 

 conserve the stream flow, which would you buy? 



Doctor VAN HISE. I would buy the headwaters of the streams. 



The CHAIRMAN. You do not understand my meaning. I say. 

 Would you buy the lower slopes of the mountains or the upper slopes, 

 assuming that you could not get both, but that you would take the 

 one which would most conserve the stream flow? 



Doctor VAN HISE. I can not make quite a satisfactory answer 

 to that, because the erosion depends on two things on the steepness 

 of the slope and the volume of the water; and, of course, the lower 

 down the slope you are. the heavier the volume of water is. There- 

 fore those uplands which should be selected first should be those up- 

 lands in which the slopes are so steep that if converted into agricul- 

 tural lands they would be p'ractically destroyed, but low enough down 

 so that they would be where the erosion would be likely to be the 

 greatest. I would not select the tops of the mountains, the flat tops, 

 because the lands on the top there would not be so easily washed off 

 because they are flat, in the first place, and because, in the second 

 place, the stream currents are not strong. But after you get over the 

 top and down these slopes here and the streams have gotten the 

 volume so that the erosion would be great and the slopes are steep 

 there; joining those two factors together and picking out the area in 

 which the damage would be the greatest by the removing of the for- 

 ests; those would be the areas which I should select if it were left 

 to me. 



The CHAIRMAN. Suppose I had a cone here approximately the shape 

 of a mountain, sitting in a panfull of water: suppose I tie a sponge 



