Horse Manure Compost
The Renewable Resource
Dr Ann Swinker,
Penn State University
How Much ?? Waste Space
One 1,000 lbs. horse produces ~45 lbs.
manure daily+ Bedding
= 730 cubic feet/year of waste to manage
per 1,000s of animal.
Manure Handling Site
 Consider
topography and flood patterns
when developing manure facilities.
• Not near streams
• Not in Flood-prone areas
• Not on steep hillsides
• Flat, impermeable, deep water table
Dry - Manure Storage
Stock piled for future use
Composting on site
Both Require a Storage Site
 Select
a high dry spot
 Keep away from bodies
of water
 Easily accessible
 Confine the pile
 Treat any runoff
Traditional Use of Manure
Commercial fertilizer
 Manure
vs.
Manure
contains organic matter
 Organic matter is good for soil health &
structure
Applying Manure/Bedding Fresh
 Improve
the health
of grass
 Apply according to
soil test
 Good idea to keep
animals off pasture
for a few days
 When weather
permits
Haul Off the Property
 Haul
manure & stall
waste off property
 PA
Mushroom Growers
contact with horse
farms to remove
manure and straw.
 Compost
all stall waste
Composting

Natural aerobic process for
stabilizing organic matter
Well composted manure has humus
smell, 25-50% volume reduction,
and destruction of pathogens and
weed seeds due to heat of
composting.
 Simple,
easy.
 Natural biological process.
 Recycling.
 Bio-secure.
 Environmentally sound.
 Low odor.
 Low fly production.
 Mechanical
breakdown
of large particles
 Increase surface area
for microbes
 Feed on bacteria and
fungi.
Microbial activity is related to
availability of food source, surface
area, moisture and oxygen
availability.
Composting Principles
Cone Shaped Windrow
“Chimney effect”
Unimproved Surface
Active vs. Passive Composting
Actively Compost
Requires turning, moisture, oxygen, C:N
Properly composting manure – Heats
up to 145 degrees F
can kill parasite eggs and weed seeds
22
C:N ratio
 Oxygen Content (Porosity)
 Moisture Content
 Temperature
 pH
 Particle Size

• Active composting occurs in the
temperature range of 50oF to 160oF
• Pile temperature may
increase above 140oF but
this is too hot for most
bacteria and decomposition
will slow until temperature
decreases again.
Remember, Compost pile heat is the direct
result of microbial metabolism!!!
 Supply
of total carbon compared to total
nitrogen in compost pile.
 If C:N is too high the compost process
will slow.
 If C:N is too low, more likely to lose
Nitrogen as ammonia gas or in leaching.
 Ideal initial C:N mixture range is
20 – 30:1.
 Very important!
Curing
Phase
Temperature (F)
Active
Phase
140
Thermophilic
100
Mesophilic
2
4
6
8
Weeks of Composting
Need
Oxygen for most efficient
process.
21% oxygen in air.
5%-10% is optimal for compost
process. <5% process slows.
As pile heats more oxygen will be
consumed by microbes.
40-65% moisture range
Optimal
conditions
for microbes
0%
Too Dry
50-65%
100 %
Too Wet
0
7
Fungi (5.5-8.0)
Bacteria
(6.0 – 7.5)
14
C:N Ratio - 20 to 30:1
% Moisture - 50-65%
Oxygen - 5-10%
pH - 5.5-8.2 (acceptable)
Particle size - 1/4 to 3 inches
Temperature -110 -160 o F
Mixed sizes are preferred.
Wood shavings ideal.
Solid Manure Storage




Covered facilities
Tarp may provide cover
with less cost and more
labor
Stack or stockpile in a
well-drained area for
later hauling
Regulations may require
runoff control
Choosing a Manure Storage Facility
 Land
application
methods,
 Type of bedding
 Hauling, distances,
volume
 Space and size
requirements
 Treatment
 Common Since!!
•Design system to
fit your goals
•Storage area?
•Consult NRCS
Manure Compost Bin
Two Bin Composter
Economy Model
Size Matters
Other Uses of Composted
Horse Manure
Landscaping - Gardening
Riding Arena Footing
Compost- Use on Sustainable
Trails as Footing
Mortality Compost Management
 Animal
bedding
 Waste feed
 Manure
 Straw
 Wood shavings,
sawdust, woodchips
 Others?
For large animals
 Land apply after 90 more days
 Six months total
 or use on new composting row


Bones from immature
animals degrade
quickly and can be
land applied.
Big bones from mature
animals may need to
be picked out.
Factors Affecting
Odor Release and Dispersion
1. Wind speed
2. Area
3. Source concentration
1. Temperature
2. Wind speed
3. Topography
Summary - Manure Management
 Each
farm should have a plan for managing
manure spreading and disposal.
 Store manure in a dry, level, impermeable
location free from storm-water runoff.
 Manage storm-water to prevent manure
contamination of water and eliminate runoff.
 Actively compost manure and bedding
 Control animal access to manure pile sites.
 Visual – out of sight-out of mind
Questions????