1046 



Pit, Trench and other Silos. 



[Feb., 



PIT, TRENCH, AND OTHER 

 IMPROVISED SILOS* 



A. W. Oldershaw, M.B.E., B.Sc, 



Agricultural Organiser for East Suffolk. 



The ensilage system in farming seems to be rapidly 

 increasing in popularity in this country. The chief obstacle 

 to its further extension appears to be the very high cost of 

 concrete or wooden silos, and it is desirable, therefore, that 

 all other methods should be considered which would involve a 

 smaller outlay of capital and would give satisfactory results. 



Pit Silos. — In previous issues of this Journal\ attention has 

 been drawn to the making of silage in " trenches." The 

 term " trenches " has been used to describe rectangular 

 holes, 3 or 1 ft. deep, as distinguished from the cylindrical 

 " pits " of about 20 ft. or so in depth and 12 to 16 ft. in 

 diameter, used in America. Deep pit silos can only be used 

 where both soil and sub-soil are very dry, so that there is no 

 fear that water may have access. Silos of this nature were 

 excavated some years ago by Mr. H. C. Boggis, of Wrentham, 

 Suffolk, on his farms at Easton Bavents, near South wold. 

 There is not always sufficient green material available to fill 

 the silo, however, since the land at Easton is very light and 

 subject to drought, and Mr. Boggis keeps on his arable land 

 a flock of sheep, which in a dry May and June require all 

 the green food he can grow. When filling this pit silo the 

 green material is simply chaffed and allowed to fall into the pit, 

 until the latter is full. Galvanised iron is arranged round the 

 pit to a height of 6 ft. to enable the green stuff to be heaped 

 above the ground, since the material sinks when allowed to 

 settle. The silage is removed from the pit by means of a 

 hoist. 



In America, where this type of silo is quite common, the 

 inside of the pit is often lined with cement. The best way 

 to construct such a silo is to excavate a circular hole of the 

 required diameter a few feet deep, line the side with cement, 

 and then continue excavating and cementing until* the required 

 depth is reached. The bottom of the pit may also be lined 



* A paper read at the Agricultural Organisers Committee of the Agriculture 

 Education Association held at Cambridge, July 1920. 



f"A Simple Method of Making Silage,' July, 1919, p. 450; and 

 " Preserving Green Fodder — An Inexpensive Trench Silo," April, 1920, p. 65. 



