24 September 2013

3 minute read

Silo maintenance is an overlooked area on many dairy farms, according to Cynthia Martel, Extension Agent at Virginia Cooperative Extension. Down time during harvest can be a costly mistake—one that can be avoided with preventive maintenance.

Most farmers start filling an empty silo first in a new harvest year, which allows the silo to be thoroughly inspected, writes Cynthia.

If a considerable amount of feed is still in the silo it will be hard to assess the structure. Silage can produce acids that will over time erode concrete or unprotected metal and lead to severe silo deterioration.

Removal of all old feed will allow the inside surfaces to be examined along with the outside. Some key areas to look for damage on horizontal concrete bunker silos:

• Cracked sidewalls = Leaky silos allowing for more air ingress, leading to more problems with heating and spoilage resulting in feed loss, or structural failure during packing or after which can cause serious injury or death.
• Cracked concrete or pavement, or rutted floors = allows for air pockets, pooling of water or spoiled seepage, and loss in tractor or truck traction.
• Many dairy farms throughout Virginia also use trench silos—an unlined horizontal silo— typically with dirt sides. (A trench silo should be lined if it becomes a permanent structure.) These structures with open dirt floors and side walls need considerably more maintenance and work than a typical concrete silo.

These trench silos with dirt walls and floors deteriorate over time, due to weather and use. Additionally, the dirt walls of these silos are never smooth which allows for air pockets, seepage, standing water, and a number of other problems that can lead to poor quality feed and management issues.

Another type of silo that is often used is the upright silo. Maintenance and preharvest inspection on an upright silo is more involved because they have lots of moving parts that need to be inspected along with the structure itself. There are unloader suspensions and cables, silo chutes, doors, fill pipes, hydraulic lifts, ladders, cages, roofs, hoops, and the walls of the upright itself to inspect.

It is best to make a checklist of every part to be inspected—right down to the smallest one. The bolts and nuts that hold the hoops in place and the concrete slab or walls the silo might be sitting on or made out of can cause an entire upright silo to collapse if not properly secure.

The Corn Belt of the United States over the last few years has seen several fatal accidents that occurred as a result of upright silos failing and either exploding or collapsing.

A good start to a checklist for any type of silo could include the following:

1. Cracked concrete sidewalls.
2. Cracked concrete flooring.
3. Uneven floor pad - Places where water or
seepage can settle.
4. Dirt side walls or floor showing considerable damage from tractors or weather –
consider lining.
5. All mechanical parts in good to great working order.
6. All mechanical parts are free from debris
or old feed – which could cause malfunction or fire.
7. Upright silo is standing in vertical position
with no tilting.
8. Upright silo walls and roof are in good to
excellent condition – repairs made if needed.
9. Correctly sized silos = incorrect sized silo
can affect silage quality and feed-out
rates.

It is important to seek professional opinions about a silo structure that may need repairs. Improper repairs or ignoring the problem will be costly, if not fatal in the end. A safety checklist should be in place for any silo on the farm, whether horizontal or vertical.

If you need assistance developing a preharvest safety checklist, your local Extension Office can help put one together.