No. 7. DEPARTMENT OF AGRICULTTTRE. 243 



ME. RODGEES: V\'^hy will a tree not grow with the leaves all 

 plucked off as they grow? 



PROF. MASSEY: The leaves are the laboratory of the plant; 

 they construct everything that tends to make growth, and without 

 a laboratory for the plant, you can't get the growth, of course* 

 There are some things like the evergreen tree, or the passion plant 

 or like the cactus plant that act in the same way as leaves. 



MR. J. W. COX: Can as good results be obtained by plowing 

 manure under as applying it to the surface of the soil on a grass 

 crop? Can the same value in plant food be obtained, or is there 

 any loss in plant food by plowing the manure under? Will the 

 plant food in manure, plowed under leach away beyond the reach of 

 ordinary farm crops? 



PROF. MASSE Y: V\^ell, I should say that would depend upon a 

 great many conditions. We have found in certain experiments 

 that manure spread in the fall on the surface and let lie there all 

 winter — we have compared that manure plowed under at the same 

 time, and other manure applied in the spring and plowed under 

 when the whole was plowed, and we have found that that manure 

 that was applied in the fall and let lie there on the surface all winter, 

 gave the biggest crop of the three. That was one single experiment 

 and made at the New Hampshire Experiment Station. Now one 

 Swallow don't iliake a summer, but as a rule I have found in the 

 South — now climate and conditions differ — but as a rule I have 

 found in the South the nearer you can keep the manure to the sur- 

 face, the bettor, because it adds there a mulch and tends more to 

 preserve the humidity of the soil. Therefore I believe that the best 

 way to use manure is to keep it as near the top of the ground as pos- 

 sible. 



MR. COX: How many pounds of nitrate of soda is necessary per 

 acre for a top dressing of an old meadow, where the soil is in a fer- 

 tile condition? 



PROF. MASSE Y: None at all, if the soil is in a fertile condition. 

 The question assumes that the soil was not in a fertile condition; 

 that it needs nitrate of soda. Nitrate of soda is a very good thing 

 for some land for a grass crop, but as I have said, we ought to farm 

 economically. It is necessary to produce an article so as to leave 

 to the farmer the largest margin of profit without injuring his laud. 

 Some years ago a man down in South Carolina made 254 bushels of 

 corn on an acre, and if he hadn't got a premium of |500 from "The 

 American Agriculturist" and §500 from the State of South Carolina 

 he would have lost money on it. so that the average good farmer 

 wants to make good crops with the margin of profit on his side, and 

 not to spend more than he receives in return as some millionaires do. 

 Now I should apply — if I had special need for stimulating a crop of 

 grass — I should apply about 100 pounds per acre of nitrate of soda. 

 It is a very good thing, and in a great many cases it may be very 

 profitable. 



QUESTION: At what season of the crop would you apply this 

 nitrate of soda? 



