463 MINNESOTA STATE HORTICULTURAL SOCIETY. 



all, be utilized in the chemical preparation of the meals which the 

 growing crops demand. 



The conservation of moisture in a fallow field is comparatively 

 an easy matter. A light, shallow, powdery dust blanket, renewed 

 by harrowing whenever a crust is formed, and complete eradication 

 of weeds, are all that is required. Cultivated crops, like corn, pota- 

 toes, beans, beets, carrots, peas, etc., are not much harder to manage, 

 because in good farming the weeds ^niist be cleaned out, and the best 

 way to dispose of them is by repeated, shallow cultivation, begun 

 early when the weeds are small and easily killed and kept up through 

 the season — and this is the most approved way of making a dust 

 mulch. Of course, in a dry time capillarity will not furnish all the 

 water necessary for the welfare of the crops unless the subsoil is 

 completely saturated in the early season and underlaid with clay 

 or impermeable rock which does not slope enough to allow the sur- 

 plus water to drain away toward some river or follow the general 

 slope of the country in the direction of the sea. Egypt offers a good 

 illustration of the advantage of thorough saturation and a good dust 

 mulch to prevent surface evaporation. Only the most intense culti- 

 vation will warrant any attempt to ameliorate the unfavorable con- 

 ditions which induce loss by leaching, except by the introduction of 

 humus. Pulverizing the top soil, however, to the depth of two or 

 three inches entails little expense, insures a better crop for the cur- 

 rent year and forestalls the usual growth of weeds for the next year. 



Carefully conducted experiments have shown that a good garden 

 loam when pulverized will absorb only half as much water as before, 

 and when the conditions are the same it will be more than twice as 

 long doing it. When the pulverized earth lies loosely on the soil 

 in its natural state, with no established connection between the pores 

 of each, the time is indefinitely increased. It is true that the force 

 of capillarity increases with the fineness of the soil, and up to a 

 certain point this is also true as regards the fineness of the grains 

 which compose the soil, but when these are very fine and floury the 

 interstices become so clogged as to well-nigh shut ofif the upward 

 movement of water altogether. In such lands deep plowing and 

 subsoiling only will ameliorate the natural condition of the ground, 

 and the pulverized surface will check the up-creeping water, offering 

 it to the plant roots before the air can lay its clutches upon it. 



To prevent the loss of water by leaching, little can be econom- 

 ically done. Increasing the amount of humus by plowing in green 

 manures and the admixture of a small quantity of clay with sandy 

 soils make them more retentive. 



