The effects of drouth are diminished owing to the large and deep- 

 ened soil bed and the more favorable condition of the surface for 

 preventing excessive evaporation of moisture. 



It aids in making new soil out of the unprepared elements since 

 it permits a free entrance of air and amtospheric heat, which dis- 

 integrates soil material hitherto unavailable for use of plants." 



Depth of Root Penetration 



Much misapprehension exists among agriculturists regarding the 

 depth to which roots penetrate the soil. It is a general belief that the 

 roots of cultivated crops do not reach to a greater depth than one or 

 two feet. 



Corn roots have been found to penetrate four feet deep and to 

 fully occupy the soil to that depth. On drier and deeper soils they 

 went as deep as eight feet. Roots of small grains, such as wheat, 

 oats and barley, penetrated the soil from four to eight feet and even 

 ten feet in depth. -Perennial grasses have been found to go to a depth 

 of four feet the first year and five and a half feet the next year, and 

 they probably go considerably deeper during succeeding years. 



Other crops have gone to the following depths: Potatoes, three 

 feet; sugar beets, four feet; alfalfa, thirty to fifty feet. The buffalo 

 berry penetrated the soil to the depth of fifty feet in Nebraska. In 

 California, grape vines went down twenty-two feet; flagwort more 

 than ten feet ; goose foot, eleven feet, and hop plant, eight to ten feet. 



Most of the above results were obtained in humid or sub-humid 

 regions. Soils and climate differ in such a way as to favor a some- 

 what deeper root penetration in arid regions, hence it is natural to 

 expect to find roots at even greater depths than the above. 



The conditions which encourage deeper rooting are drainage, limit- 

 ed supply of moisture and a soil porous and fertile to a great depth. 

 Deep, early cultivation also forces roots to seek the lower depths. 

 Deep rooted plants are much more drouth resistant, due to the lower 

 water supply during periods of drouth. They also have a larger feed- 

 ing area, and the fertility of the soil is not depleted so quickly. 



Subsoiling With Red Cross Dynamite 



This is the ideal method for breaking up compact subsoil whether 

 this compactness is due to plow sole or natural hardpan, because it 

 breaks up the compact subsoil without throwing the subsoil on top of 

 the topsoil or mixing the two. 



The objection to mixing virgin subsoil with old topsoil is that the 

 former contains very little hurnus and unless heavily fertilized is dis- 

 advantageous as a topsoil until one or two years after it has been 

 broken up, when the action of air and moisture and the penetration 

 of roots and other vegetable matter shall have nitrated it. 



The method of subsoiling with Red Cross Dynamite is very simple. 

 In the average soil not underlaid with extremely tough hardpan, holes 

 one and one-half inches in diameter are put down every fifteen feet to 

 a depth of about thirty inches. These holes may be made with a dirt 

 auger or subsoil bar, or a churn drill may be obtained from any black- 

 smith which will put down the holes very easily in average soil. 



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