The following are some of several key problems of – and solutions to – producing high-quality corn silage, offered by Keith Bolsen, professor emeritus and forage management specialist with Kansas State University. For ways to prevent high shrink losses in bunker silos and drive-over piles and to reduce effluent or seepage problems, click here.

Problem: Excessive surface spoilage in sealed bunker silos and drive-over piles.


  • Pack to a minimum density of 15 lbs of dry matter/cu ft – within the top 3' of the silage surface.
  • Don't let the back, front or sides of bunkers or piles exceed a 3:1 slope; keep all surfaces smooth so water drains off easily.
  • Seal the bunker or pile surface immediately after filling.
  • Two polyethylene sheets or a sheet of oxygen barrier film under a sheet of plastic are preferred over a single sheet of plastic.
  • Overlap sheets on the forage surface by a minimum of 4-6'.
  • Extend sheets at least 6' past the edge of the forage surface around the entire perimeter of drive-over piles.
  • Put uniform weights on the plastic's entire surface; double the weight on overlapped plastic or film. Recommended weight options include: bias-ply truck sidewall disks and sandbags filled with pea gravel. Full-casing tires are used less and less because they are cumbersome, messy and provide a mosquito breeding area.
  • Use a 6-12" layer of sand or soil, or sandbags, to weigh sheets at the perimeters of drive-over piles.
  • Keep plastic in good shape during the entire storage period to prevent rodent or other damage. Mow surrounding area or build temporary fencing and regularly inspect and repair plastic.