Nc. 6. DEPARTMENT oF AGRICULTURE. 347 



lion liolds down ilio temperature of the body. A sftndy soil will 

 become warm much. more quickly than a heavy, stilf clay. The latter 

 holds water more tenaciously and evaporation continues to take 

 place, holding- the temperature down. 



Time will not ])ermit nor is it necessary to discuss the way in 

 which control of soil moisture may affect the soil temperature, fur- 

 ther than to say, that the thorougli preparation of the seed-bed, 

 upon which all good farmers insist, materially aids in preventing the 

 coniinual escape of water by evaporation and hence in bringing 

 about those conditions of temperature which are found most favor- 

 able. The formation of a mulch by cultivation as early in the 

 spring as possible will arrest evaporation and avoid the unnecessary 

 cooling of the soil which accompanies that operation. At the same 

 time, the warmth of the sun instead of being used up in evaporating 

 the w^ater will be absorbed by the soil. It is not necessary to at- 

 tempt to bring these conditions about to any great depth but merely 

 sufficient to permit of the early warming of a few inches of the 

 surface soil. 



The CHAIRMAN: We will deviate a little from the program, as 

 T presume the Committee on Queries have some questions they want 

 answered, and we will have them presented now. 



MR. S. S. BLYHOLDER, Chairman of the Committee on Queries: 

 The first question is addressed to Dr. Thayer: 



"Is it practical to grow corn year after year, depending on crimson 

 f lover as a catch crop to maintain humus in the soil?" 



DR. THAYER: As far as the humus is concerned, it is pos 

 sible; but it is not concerning other elements of fertility, and a ro- 

 lation is better on that account. Now, it is not possible to raise 

 crimson clover in dense corn fields, where the corn is high and with 

 heavy blades and the ground shaded. You cannot depend upon it 

 as humus for you cannot raise it. There would be humus enough 

 there for the ground if you could get it, but by and by the phos- 

 phoric acid would become scarce. 



MR. BLYHOLDER: The next question is addressed to Professor 

 Wells W. Cooke: 



''How does oats and pea hay compare in feeding value with the 

 ordinary mixed clover and timothy hay?" 



PROF. COOKE: As far as the feeding value is concerned there 

 would not be much difference; but, of course, the proportions would 

 be, that is, the pea hay will have the largest proportion of diges- 

 tibility; the clover will come next, while the oat hay, if cut w^hen 

 the oats are in blossom, would have about the same percentage of 

 digestibility as the ordinary mixed clover and timothy hay we have 

 on o«r farms. 



