STATE POMOLOGICAL SOCIETY. * 125 



good many feet to get a well, so that the water table is quite low. 

 It is excellently drained. 



Ques. May I ask, Do you maintain the clean tillage during 

 the entire season ? 



Prof. Stewart : This clean tillage is stopped in the middle or 

 latter part of July, just as the tillage is stopped on the plats 

 receiving cover crops, so that the difference will essentially be 

 that in one case we have merely the natural growth, weeds, and 

 so on, following the cessation of tillage, and in the other case 

 we have a definite cover crop. 



Ques. What I learn from this mulch system on your land is 

 that the trees respond to it better than they do to tillage, and 

 that more moisture is conserved by the mulch than by the till- 

 age? 



Prof. Stewart : Yes, there isn't the slightest doubt about that 

 point, because we made the moisture determinations this fall 

 very carefully and thoroughly and under almost ideal condi- 

 tions. We took them about the loth of September, after one of 

 the most severe drought periods that we have experienced in 

 recent years. It was a severe test on the different cultural 

 methods. It was, however, a comparison of the moisture con- 

 ditions about six weeks, or even eight weeks, after the tillage 

 had stopped, you understand. In other words, we compared the 

 moisture conditions on the tilled plats at the close of the active 

 season with the moisture conditions under the mulch treatment 

 at the same time. We found that the moisture content under 

 all of the tillage systems ran from about five to eight per cent of 

 moisture in the surface foot of soil. It was almost dust dry. 

 In other words, it contained about five to eight per cent of 

 moisture, but trees can hardly extract moisture from soil below 

 seven or eight per cent, so that most of those trees were existing 

 in a state practically of complete drought. At the very same 

 time we found that under the mulch there was 17 to 18 per cent 

 of moisture. The soil was. quite moist to the 'touch. The 

 optimum, or the best moisture content possible in that soil is 

 2o7o. We had 17 to 18%. This means that even at the end 

 of a very trying period we had 85 to 90% of the best possible 

 moisture content surrounding the roots of the mulched trees, 

 while those under tillage were practically in a state of drought. 



