4G2 Bureau or Farmers' Institutes. 



wooden structure. Since the air pressure in the silo is outward 

 and not from without inward, we need not concern ourselves 

 greatly if the silo is water-tight. Is the stave silo water-tight 

 when properly constructed? We have used several stave water 

 tanks constructed on the principles of beveling the staves, so that 

 when set up and hooped, the edges of the staves touched only 

 about one-third of their width. As the hoops on these structures 

 are tightened, the inside edges of the staves are crushed and made 

 water-tight. In order to prove that the farmer could construct 

 water-tight silos, we had staves prepared with unbeveled, sawed 

 edges. These when set up were hooped with the ordinary silo hoop 

 of commerce. This tub was placed on a temporary wooden bottom, 

 and so treated that a water-tight joint was secured where the 

 ends of the staves joined the bottom. This small silo of four feet 

 diameter and four feet high was filled with water, and it proved 

 to be water-tight from the first. It was left out in the open during 

 the entire summer, some times full of water, some times nearly 

 empty, and yet it never leaked when refilled, although for a 

 part of the time there were but two hoops on it, and although the 

 staves were but two inches wide. From this and other experi- 

 ments,, I conclude that if fairly well seasoned, sound timber is 

 passed through the saw to secure rough, straight edges, and a 

 uniform width of stave, a water-tight silo may be secured, pro- 

 vided that in the large silo the edges of the staves are not beveled, 

 and in small ones, beveled slightly. My judgment is that few silos 

 with air-tight walls will ever be constructed, for if they are vir- 

 tually water-tight, reasonably durable and cheap, the practical 

 limit of perfection will have been reached. 



As yet we have not had sufficient experience to determine 

 whether bands of woven wire fencing or round hoops are the best. 

 Either kind is good. I think all will agree that some loss of dry 

 matter occurs whether roughage is left in the field for a time and 

 then put under cover, or placed while green in the silo. Which 

 treatment results in the least loss has not been definitely deter- 

 mined, and probably never will be, since the conditions in the silo 

 or in the field are not alike from year to year, and it has not yet 

 been determined what kind of a silo preserves green material 

 best. Some investigations in an Experiment Station indicated 

 that greater losses occurred in the stave silo than in another con- 

 structed on a different principle, but there is no data showing that 



