Composting

Composting is a natural way of reducing livestock manure and bedding into an excellent soil amendment and fertilizer.  It can be used on the farm for pastures, incorporated into garden soil, or made available to other gardeners.  Composting can be done in a limited area without causing odor or appearance concerns AND even creates a valuable commodity!

Basic Ingredients

Raw materials - Livestock manure provides necessary nitrogen and initial moisture.  Cattle, horse, poultry, sheep, goat, and rabbit manures are very good composting materials.  Swine manure with its high moisture content and odor is more difficult to compost.  It will compost best if mixed with a dry, high-carbon bedding and aerated regularly.

Oxygen - Oxygen levels that support aerobic organisms must be maintained by aerating the pile regularly.  If the supply of oxygen is limited, the composting process slows.  Without sufficient oxygen the materials become anaerobic and odors become a concern.

Moisture - Moisture must be present to permit biological activity without hindering aeration.  Water provides the medium for chemical reactions, transports nutrients, and allows the micro-organisms to move about.

Temperature - Composting takes place within the range of 110º and 150º F.  These temperatures are desirable because they destroy pathogens, weed seeds, and fly larvae in the composting materials.  Regulations set the critical temperature for killing human pathogens at 131º F.  This temperature should destroy most plant pathogens as well.  The critical temperature for destroying most weed seeds is 145º F.

Methods

The simplest way to compost is to place manure in a pile on an impervious surface such as concrete or a tarp on a high, dry location, and place a tarp over it during the rainy season to protect nutrients from leaching away.  If bedding is not already mixed with the manure, add wood shavings, straw, sawdust, dry leaves, or shredded newspaper.  The necessary ingredients of carbon and nitrogen are now present.  Decomposition using this method will take about one year and compost is then ready to be used.

In a Hurry? 

To speed the process to as little as 60 days, build bins or enclosures in locations near barns or the animals.  An 8' x 8' x 4' bin is easily accessible to wheel barrows or small equipment.  Locate your stockpile on a hard, impervious surface so driving and walking access is good in all weather conditions and nutrients do not leach away.

For large operations, windrows offer an efficient alternative.  Manure and bedding are collected in long rows (windrows) on earthen, synthetic, or concrete pads.  Windrows are initially about 3 feet high and are easily managed up to 6 feet high with a bucket loader.  Tractor equipment is used to aerate the windrows by turning the rows over.  The important effect of turning is rebuilding the windrow's porosity.  This improves passive air exchange and exposes all materially equally.  With frequent turning, compost can be ready in less than 60 days!

Ready?  Set?  ...Compost!

• Provide for easy access to water at the stockpile area.
• Make sure to wet the bedding in the middle of the load as new loads are delivered to the pile.
• The pile should be about as damp as a wrung-out sponge.
• Adding water in the dry months and covering with a tarp or roof during the rainy months is necessary.
• The pile should be turned and mixed frequently, with material on the top moving to the bottom and outside material moving to the inside.  This mixing adds needed oxygen that significantly reduces odors.
• Check moisture levels at the same time you turn the compost.
• Check the center of your pile for warmth - heat indicates the pile is composting.  This heat occurs in fresh, moist, organic material for 4 - 8 weeks and indicates fast breakdown activity.
• Don't allow puddles or wet edges of the compost pile to develop.  Shovel them into the middle of the pile to reduce flies and prevent runoff to other surface water bodies like streams or ponds.

The Kitsap Conservation District can assist you in creating a plan for manure composting.  Cost share funds are available by application to support waste management and many other conservation management activities.  KCD maintains a Manure Hotline that links farmers and gardeners.  Call the District for more information at (360) 337-7171.

Click here for designs for a standard 8'x8'x4' compost bin.

1386 SE Lund Ave. Suite 1, Port Orchard, WA  360-337-7171 FAX 360-337-7172