136 MINNESOTA STATE HORTICULTURAL SOCIETY. 



THE CAMPBELL METHOD OF OVERCOMING DROUTH. 



A REVOLUTION IN FAKMING IN THE SEMI-ARID STATES. 



(Extract from an article by J. Herbert Quick in tlie Salt Lake Herald.) 



With an annual precipitation of not far from twenty inches of 

 water, crops ought to be successfully grown every year unless the 

 water is used up in some way aside from the growth of plants. An 

 iach of water weighs in excess of 100 tons an acre, and twenty inches 

 more than 2,000 tons. A growing plant does not need, during its 

 period of growth, more than 300 times its dry weight. It is a very 

 good crop, indeed, which, dried, weighs more than thirty tons to 

 the acre. Therefore, 900 tons ought to be enough for the actual use 

 of any crop. The reader sees, as Mr. Campbell saw, that even after 

 growing a good crop, 1,100 tons of water ought to be left over, un- 

 less somehow the water had slipped away and played truant. 



In the spring the " semi-arid belt " blossoms as the rose under the 

 influence of the vernal rains; but June, July and August bring 

 hot winds which lick up the moisture, sap the vitals of the growing 

 plant and cause the evil effects of drouth. How to carry crops over 

 this period was the problem to which he addressed himself. 



The Campbell method is a reform in tillage. It rests on three 

 foundation stones— deep plowing, subsurface packing, frequent 

 shallow surface cultivation. The objects of these operations are to 

 form an ample reservoir in the root-bed for moisture, to promote 

 capillary attraction, to draw up moisture from beneath and to pre- 

 vent the escape of moisture by evaporation from the surface. 



The prairie soils have lain for centuries in the same position^ 

 and are filled with channels washed out by the downward flowing 

 rains which prevent the lateral movement of moisture by capillar- 

 ity. This old structure is broken up by deep plowing — not sub- 

 soiling, the ordinary plowing from seven to nine inches deep. But 

 any sort of plowing leaves cavities in the ground. The furrow slice 

 is loosened up as it turns, and some treatment is necessary to give 

 the soil that homogeneous firmness necessary to the retention of a 

 large quantity of moisture. Mr. Campbell tried the roller. It would 

 not do. It packed the surface, but unless enormously heavy, it left 

 the bottom cavities unaffected. So he invented a sub-surface pack- 

 ing, the one new thing he has given to agriculture. He invented a 

 tool which firmly packs the sub-surfaces and leaves the upper four 

 inches loose. He gives his audiences directions for doing this work 

 with the ordinary tools of the farm, but, no doubt, special tools will 

 always be used where large fields are to be economically packed. 

 This packing is done only once a year and costs oulj' 20 cents per 

 acre for labor. 



The ground is subjected to frequent shallow cultivation to pre- 

 vent the evaporation of moisture. Ever}^ farmer knows that a layer 

 of straw over a garden bed will keep the ground beneath moist. 

 Mulching around the roots of trees does the same thing. This is 

 done by checking evaporation. Almost every farmer knows that 



