Value of Roofing Tower Silos and of Paper and Earth Covers for Trench Silos

Abstract

In its silo-building campaign the Department of Agriculture and Commerce and the Agricultural Extension Service fieldmen have often been asked to make recommendations about the relative benefits of the roof in tower silos and the use of cover in trench silos. The problem arose when a local firm began constructing roofless silos, and the cost of covering the material in big trench silos began to be considered, as well as the removal of that cover when the silage was to be used. An experiment was conducted to determine whether it was necessary to cover the trench silos, and whether the roof was necessary in tower silos, judging from the extent of top spoilage and the general quality of the edible portion. The findings apply, of course, under Puerto Rican conditions. Covering is necessary for trench silos. So much surface is exposed that the resulting top spoilage is very large if the contents are not protected. According to the results obtained in this experiment a roof is not necessary for tower silos; no better quality silage and no less top spoilage were obtained by its use. If unloading equipment is to be used, though, a roof will protect such equipment. Another fact to be considered is the following: It was found in the work reported here that the absence of a roof permitted filling the silo up to the edges, and also a more thorough trampling of the material. The same results can be obtained with domed roofs. Flat roofs will not permit a thorough trampling of the material up to the edges because men cannot work inside the silo at that level.