FOURTH ANNUAL YEAR BOOK— PART VI. 379 



pruning or cutting off the roots of the corn plants. The roots were cut 

 off at different depths in different rows, about six inches from the hill 

 (on all sides of the hill) three times during the season. The entire 

 field was cultivated with a weeder in order that the cultivation would 

 not interfere with the experiment. One row was pruned and one row 

 not pruned throughout the field alternately, ^o that a close and accurate 

 comparison might be made of the effects of root injury. The results of 

 an average of the three years' work are as follows: 



Not pruned 62 bushels per acre. 



Pruned two inches deep 60 bushels per acre. 



Pruned four inches deep 45 bushels per acre. 



Pruned six inches deep 30 bushels per acre. 



At the past winter's farmers' institutes the question was fre- 

 quently asked, "Would deep early cultivation injure the plant?" In 

 answer to this inquiry the acompanying photographs are shown. 

 The young plant was taken up twenty-one days after planting and the 

 root system washed out. At this time the roots spread from one side 

 of the row to the other neai: the surface of the soil. The root develop- 

 ment of the mature plant similarly washed out shows that there is a 

 perfect network of roots in the surface soil. In fact, these surface roots 

 largely supply the plants with the plant food from the soil. The deep roots 

 anchor the plants and hold them in an upright position. Deep 

 cultivation would doubtless cut off and destroy many of these impor- 

 tant roots, I have seen men pull out bunches of corn roots from the 

 cultivator shank at the end of the row. The amount of damage from 

 such injury will vary with the season. In a dry season the injury 

 must be very great. In a wet season the injury will be less 

 because the remaining roots will be able to supply the necessary mois- 

 ture for plant growth. 



S'ome of the letters indicate that the writers have secured better 

 results with deep cultivation than shallow cultivation. If this is the cas*-^, 

 then it is the best system for them to follow under their conditions. How- 

 ever, in Illinois the majority of farmers will get better results from shal- 

 low and frequent cultivation. If the seed bed has been properly handled, 

 disced, plowed, disced, harrowed and planted there will be few weeds tO 

 eradicate in the field. It will not be necessary under these circumstances to 

 cultivate deep. The shallow cultivation, stirring the surface, will de- 

 stroy the small weeds and conserve soil moisture, the two principal ob- 

 jects of com cultivation. 



Illinois Experiment Station. 



