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Careful investigations of windbreaks and their influences in the 

 States of Iowa, Nebraska, and Kansas point toward the following general 

 conclusions : — 



Windbreaks inevitably damage crops immediately adjacent to them in 

 three practical ways : — (1) By sapping moisture otherwise available for 

 the agricultural crops ; (2) by shading ; and (3) by subjecting adjacent 

 crops to damage from frost, clue to stagnation of the air in their lee. 



On the other hand, windbreaks directly benefit crops (1) by retarding 

 dry winds and thus decreasing evaporation ; (2) by impeding cold winds 

 and thus modifying the average temperature ; and (3) by breaking the 

 force of severe winds which would otherwise break down and injure 

 portions of the crop. 



For all crops the advantages of good windbreaks far outweigh their 

 objectionable features. The beneficial effects extend to a considerable 

 distance — ten or more times the height of the trees — from the windbreak, 

 while the injurious effects are for the most part quite closely confined 

 to the immediate vicinity of the windbreak. Actual measurements show 

 that the yield of crops protected by windbreaks, while considerably less 

 where close to the trees, is well above the normal yield of unprotected 

 crops for a great distance out from the windbreak. The increase takes 

 the form of a curve, lowest near the windbreak, rapidly reaching a crest 

 at a distance from the windbreak of about one or two times the height of 

 the trees, and gradually tapering off to a normal yield at a point usually 

 over eight or ten times the height of the trees. So great is this increase 

 that it has been reliably estimated that a shelter-belt twice as wide as 

 the trees are high will pay for itself in the increased productivity of the 

 protected field, without taking into account the value of the wood pro- 

 duced. The damage from shading and sapping varies with the kind of 

 crop, but the protective influence is felt by all crops. 



In the Western States it is recommended that windbreaks be always 

 planted in an east and west direction, since in this position they are most 

 likely to retard the prevailing winds. The composition of windbreaks is 

 of considerable importance. Windbreaks of cottonwood trees are on the 

 whole the best, since they attain a good height without causing excessive 

 damage from shading. Osage orange, honey locust, silver maple, and a 

 number of hardier conifers such as Scotch pine and white spruce have 

 also proved very satisfactory for windbreak purposes. Windbreaks should 

 always be made up of several rows of trees, since a single row is much 

 less efficient as a protection from wind, while the damaging effect to the 

 crops is practically the same. 



I next proceeded to the Department of the Interior, where I called 

 upon the Commissioner of Lands, Mr. Fred. Dennett, in connection with 

 a subject in which I have long been interested, viz.. Land Settlement. 

 The Commissioner spoke eloquently of the free homestead in the develop- 

 ment of America : but emphasised the need of a strict" residential clause 

 to prevent fraud. In answer to the question : "What should be the size 

 of a farm in the dry regions," he replied : "A family unit, or, in other 

 words, the smallest area that will support an average-sized family. There 

 should be no hard and fast rule as so much depends on the locality. 

 As far as possible, land laws should be treated as local or State problems. 

 In the past the United States Government made the serious mistake of 

 applying the same unit to all States which came under the Homestead Act. 



