DRY FARMING CONGRESS. 



18a 



In the experiments mentioned above conducted at Encinal, we found 

 that steers being fed for the market consumed about 75 pounds of pear 

 per day. The milk cows at San Antonio consumed about 140 pounds. 

 The average consumption would therefore probably be in the neighbor- 

 hood of 100 pounds. These figures, taken in connection with the yield 

 which we have secured during the past three years, would indicate that 

 roughage for about 1 1-4 cows can be grown upon one acre of ground. 

 In order to be conservative, suppose we estimate it at one cow per acre, 

 which seems, from the returns, to be perfectly safe. Even this is better 

 than is done with hay in the majority of the strictly agricultural sec- 

 tions of the United States, and this crop, you must remember, was 

 grown under conditions where sorghum produced from one to two and 

 a half tons of silage per acre per annum. 



The crop is easily handled, is drouth-resistant and yields heavily. 

 It does not seem clear how it can fail to become an important adjunct 

 of the beef and butter production of southern Texas. 



PROF. KELLERMAN: This is the end of the outline of the paper 

 which Dr. Griffiths has prepared. 



You are not going to get off quite so easily,, however. I want to 

 give you a little talk of my own on "Soil Bacteriology and Crop Produc- 

 tion." 



You have heard a great many of the speakers here refer to the ne- 

 cessity of knowing something of the bacteria in the soil, and speaking 

 of the bacteriologist as the one to whom they look for explanations of 

 many things in crop production. 



There have been no explanations of any sort of just what the bac- 

 teriologist should do, or just what bacteria in the soil were supposed to 

 do. I propose therefore, very briefly, to give you an outline of some- 

 thing of the work which we have been planning to do, and very briefly — 

 more briefly still— a sketch of one or two of the things that soil bacteria 

 do when they are in their best conditions. 



It is rather a large subject — the relation of soil bacteriology to crop 

 production — for me to try to cover thoroughly. I cannot give you any 

 details. This will all be a general statement. Therefore, there will be 

 exceptions. If any of you do notice that I say anything you have seen 

 stated otherwise in print that will be the explanation for it. I am going 

 to use a broad brush here and leave out all little details. 



In the first place the various relations of bacteria . Or, rather, 



I should begin, I suppose, with the moisture in the soil for its growtli. 

 You have heard a great deal about its growth. It is something that bac- 

 teria — which also are plants — ^require for their growth. Therefore you 

 cannot have bacteria in soil with good conditions unless there is suffi- 

 cient moisture there for them to grow. As to the number of bacteria in 

 the soil, there are several millions in a teaspoonful of soil. That seems 

 like a fabulous number, but they are there. We can count them by using 

 special methods. I think you can appreciate when you have as many liv- 

 ing things in the soil as that, they must perform very decided functions. 



