194 NEBRASKA STATE HORTICULTURAL SOCIETY. 



soil under that tree or plant dryer than a contiguous yard of subsoil that 

 has not received any water from any source. 



HOW DOES PROFESSOR KING EXPLAIN THIS? 



Artificial application of water to the surface, or a shower, or a rain, 

 promptly develops a rapid evaporation from the surface. This sets in 

 motion the law of transposition of soil moisture stored in the subsoil. 

 The capillary circulation causes the moisture stored in the subsoil to 

 rise to the surface, to take the place of that lost by evaporation. Under 

 these conditions the stored moisture in the subsoil is lost by transpira- 

 tion. 



A light rainfall may not, usually does not, wet down more than an 

 inch or two, and this is speedily lost by subsequent rapid evaporation. 

 Only the heavy periods of rainfall deposit water enough in the soil to 

 reach down to and reinforce the supply of water already stored in the 

 subsoil. Hence the skilful orchardist or gardener must start his culti- 

 vator after each and every rainfall that crusts the surface. Tnis rainy 

 spring has compelled me to cultivate some of our orchards nine times 

 and we are now starting over all of our three hundred and eighty-five 

 acres of home orchards the seventh time, this within a period of forty- 

 eight days, cultivation having commenced March 20. 



Those who have conserved the very ample supply of snow and rain 

 water given us during the month of January, February, and March now 

 have a sufficient store of soil water to, with suitable tillage, carry their 

 orchards forward a number of months, depending very much upon the 

 character of the soil, the depth that water has been stored in the sub- 

 soil and the character of the past and succeeding tillage. 



We have orchard lands that would be classed as high and dry lands 

 which have not been watered in a period of twenty months, but the 

 tillage has been such as to maintain three feet of soil moisture. This 

 moisture could not be reinforced from below because, between the sur- 

 face moisture conserved by cultivation and the lower underlying water 

 table, there is a stratum of hardpan about twelve inches in depth. The 

 soil auger shows three feet of conserved snow and spring rain, one foot 

 of hardpan; under the hardpan three feet of soil gradually gaining in 

 moisture down to soil water. 



This particular orchard, now entering upon its fifth season's growth, 

 that is, the trees have been planted four years and five weeks, is now 

 coming into bloom. 



The question of what can be done by frequent tillage is to some ex- 

 tent governed by the texture of the soil. Where the soil is pliable, easily 

 worked, carrying such percentage of silt or sand as will enable the culti- 

 vator to keep it in a mellow condition it seems possible to conserve the 

 moisture from month to month and from year to year. We note, how- 

 ever, where spots of gumbo intervene that it is difficult to maintain such 

 conditions of tillage as will surely store moisture from month to month 

 or from year to year. 



