Gippsland - How Now Gippy Cow
December 2010 Edition
Holes in the bottoms of your silage bales?
Occasionally you may notice small holes underneath your silage bales where the bale sits on the ground surface. The holes in the plastic look as if someone has stubbed a lit cigarette into the plastic. These holes are most likely caused by the Underground Grass Grub or Oxycanus Grub.
These grubs can be up to about 7.5 centimetres long, five to eight millimetres wide and dark green brown or purplish in colour. They are very aggressive if picked up. They dig into the soil to eat roots but also emerge at night to eat shoots of grasses. In this case, they burrow through the silage plastic to eat the ensiled grass. They live in silk lined vertical tunnels.
Unless you are quick when you tip the bales over, you may not see them as they disappear very quickly back into their burrows. If they are thought to be a problem, move the bales to a storage area preferably a bare area where there is less likelihood of problems. If the bales are then left until they are used, further damage to the bottoms should not allow significant air into the bales.
When/if the bales are moved, check for any holes and patch them with tape specifically made for stretch wrap film. Before applying the film, the plastic must be clean, dry and of a similar colour to the film.
Contact Frank Mickan 5624 2259 or frank.mickan@dpi.vic.gov.au
