82 CAMPBELL'S SOIL CULTURE MANUAL 



not foolishly and recklessly, but at the right time and in 

 the right manner, there is needed but little more extra 

 work. 



Let us go a little further, and with just a little more 

 extra labor, and only a little, put in scientifically, and we 

 will get three times the 13 bushel yield or 39 bushels, 

 and yet a little more labor and four times the amount r 

 or 52 bushels can be grown. This has been done yes. 

 and as high as 63 and over in several instances, and the 

 60 bushel point can be easily reached in many places, 

 if the principles we shall outline are carefully followed. 

 Think of it a moment four and a-half times as much as 

 the average of all these states for twelve years. 



HOW SUMMER TILLING SHOULD BE DONE. 



Begin the work as early in the spring as the frost is 

 sufficiently out of the ground, and the surface dry enough 

 to permit the use of the disk harrow without the soil ad- 

 hering to the disk, going over the ground twice by lapping 

 the disk one half. This produces a mulch which prevents 

 evaporation; also loosens and opens the surface, so that 

 the later rains readily and quickly percolate into the soil, 

 harrowing the ground after each subsequent rain. If the 

 rain is too heavy so as to dissolve and pack the surface, 

 a second disking may be necessary, especially so if the 

 season is advanced far enough for weeds to start freely. 

 Don't at all hazards permit the weeds to grow or the sur- 

 ace to become crusted. A little carelessness here may 

 and often does make ten or twenty bushels less yield in 

 wheat, and proportionally similar losses to other crops. 



Bear in mind there are three objects in conducting 

 this work with great care. First, is to retain all the moist- 

 ure possible that may be then in the soil, for the evapora- 

 tion in early spring is very great from both the strong rays 



