|HOLMES, BRIAN - University Of Wisconsin|
Submitted to: International Silage Conference
Publication Type: Proceedings
Publication Acceptance Date: 7/13/2009
Publication Date: 7/27/2009
Citation: Muck, R.E., Holmes, B. 2009. Influence of Cover Type on Silage Quality in Bunker Silos. In: Broderick, G.A., Adesogan, A.T., Bocher, L.W., Bolsen, K.K., Contreras-Govea, F.E., Harrison, J.H., Muck, R.E., editors. XVth International Silage Conference Proceedings, July 27-29, 2009, Madison, Wisconsin. p. 277-278.
Technical Abstract: The quality of silage under reduced oxygen-permeability plastic film systems vs. standard white polyethylene film and tires was evaluated. In six trials (four in whole-plant corn, two in alfalfa), the Silostop two-step covering system (oxygen-barrier film on the side walls and top, woven plastic tarp above the top sheet, all secured to the crop by sand bags) was compared to a 0.22 mm thick white polyethylene film top sheet, secured to the crop by tires. Another trial compared a new Onestep film (oxygen-barrier film integrated with polyethylene) from Silostop with 0.22 mm thick white polyethylene film. In this trial, side wall film was used on both treatments. The Onestep was anchored with gravel bags around the perimeter and middle of sheets while the polyethylene film was completely covered with used tires. Losses in alfalfa silage (as estimated by ash content) in the top 15 cm, 60 cm from the wall were higher under white plastic compared with the two-step system (19% vs. 1%). Losses at greater depths or in the middle of the top surface were similar between the two systems. Low ash contents in corn silage made estimates of losses unreliable. However, in both alfalfa and corn silage regardless of the location, the two-step covering system had lower pH values and higher lactic-to-acetic acid ratios, suggesting the two-step system was better at excluding oxygen. The Onestep system was not as effective as regular white film and tires because the gravel bags allowed a greater dispersion of oxygen across the surface in cases where the film was damaged by animals.