COMPOSTING ORGANIC MATERIALS TO MAKE ORGANIC SOIL AMENDMENTS
REFERENCE: ON-FARM COMPOSTING HANDBOOK. 1992. NORTHEAST REGIONAL AGRICULTURAL ENGINEERING SERVICE. NRAES-54.
NRAES
152 RILEY-ROBB HALL
COOPERATIVE EXTENSION
ITHACA, NY 14853
(607) 255-7654
COMPOSTING IS THE AEROBIC DECOMPOSITION OF ORGANIC MATERIALS BY MICROORGANISMS UNDER CONTROLLED CONDITIONS
ORGANIC + O2 + BUGS = CO2 + H20 + COMPOST MATERIAL
RECOMMENDED CONDITIONS FOR COMPOSTING
REASONABLE PREFERRED
CONDITIONRANGERANGE
C:N20:1-40:125:1-30:1
MOISTURE40-65 %50-60 %
OXYGEN> 5 %> 5 %
PARTICLE SIZE1/8-1/2 IN.VARIABLE
pH5.5-9.06.5-8.0
TEMPERATURE110-150 F130-140 F
BENEFITS AND DRAWBACKS OF COMPOSTING
BENEFITDRAWBACK
SOIL CONDITIONINGTIME AND MONEY
FERTILIZER VALUELAND USE
SALEABLE PRODUCTODOR
IMPROVED HANDLINGWEATHER INTERFERENCE
LOWER RISK OF POLLUTIONMARKETING
PATHOGEN DESTRUCTIONNUTRIENT AVAILABILITY
REDUCED TIPPING FEES
FACTORS TO CONSIDER WHEN SELECTING SPECIFIC RAW MATERIALS FOR COMPOSTING
MATERIALCONSIDERATIONS
MANURESHIGH N/VERY WET
USE HIGH C AMENDMENT
ODOR IF ANAEROBIC
VARIES SUBSTANTIALLY BY ANIMAL AND HANDLING
CROP RESIDUES LOW N/DRY DEPENDING ON AGE
USE WITH HIGH N/WET MATERIAL
CONCERN WITH TRANSFER OF PLANT
PATHOGENS IF HIGH TEMPERATURES ARE NOT
REACHED
COMPETITION FOR BEDDING
SAWDUST, SHAVINGS VERY LOW N/VERY DRY
CHIPS, AND BARK USE WITH VERY WET, HIGH N MATERIALS GOOD BULKING AGENTS
GOOD MOISTURE AND ODOR ABSORPTION
CHIPS/BARK HAVE LOW SURFACE AREA AND
DON'T DEGRADE (SCREENING NEEDED)
BEWARE OF TREATED WOOD
LEAVES MODERATE N/DRY
DEGRADE BETTER IF SHREDDED
OFTEN CONTAIN FOREIGN OBJECTS IF
COLLECTED FROM STREETS
SEASONAL AVAILABILITY
GRASS CLIPPINGS MODERATE N/USUALLY WET
FINELY DIVIDED, POOR BULKING
ODOR POTENTIAL
SOMETIMES A HANDLING PROBLEM
PAPER/PAPERBOARD VERY HIGH C/VERY DRY
USE WITH WETTEST MATERIALS
AVOID COLORED INKS GLOSSY PAPER
POOR STRUCTURE = POOR BULKING
STAPLES/GLUE IN CARDBOARD
MESSY
MAY BE DIVERTED BY RECYCLING
FOOD PROCESSING MODERATE N/VARIABLE WASTE MOISTURE
MAY BE PAID TO COMPOST
ODOR POTENTIAL
VERMIN ATTRACTION (FLIES, RODENTS)
SOME POORLY DEGRADABLE MATERIAL
SLAUGHTERHOUSE OR HIGH N/VERY WET
FISH PROCESSING MAY BE PAID TO
WASTECOMPOST
HIGH ODOR/VERMIN ATTRACTION
RESTRICTIVEREGULATIONS
DIRECT APPLICATION FAVORED
AQUATIC WEEDS MODERATE N/VERY WET
SOURCE OF MINOR NUTRIENTS
TRASH IN BEACH CLEANINGS
MODERATE ODOR POTENTIAL
PAPERMILL SLUDGE MODERATE N/MODERATE MOISTURE
MAY BE PAID TOCOMPOST
POTENTIAL ODOR WITHOUT BULKING
POSSIBLE ORGANIC CONTAMINANTS
SEWAGE SLUDGE HIGH N/VARIABLE MOISTURE
SOURCE OF P
ODOR, PATHOGENS, METALS
HIGHLY REGULATED
USE A LITTLE WITH ANY MATERIAL AND LOT
MUST BE TREATED AS SLUDGE
MUNICIPAL SOLID MODERATE N/DRY
WASTE CONTAINS >50 % PAPER
ODOR POTENTIAL
INERTS (GLASS, METAL, PLASTIC)
SOME METALS
COMPOSTING RECIPES
1. QUALITATIVE PROCEDURE
- ADD WATER OR DRY AMENDMENT UNTIL THE PILE "LOOKS AND FEELS
RIGHT"
- OK WITH EXPERIENCE AND CONSISTENT MATERIALS
- BETTER TO ANALYZE AND USE FORMULAS
2. SIMPLE FORMULA FOR TWO INGREDIENTS
- A BALANCING ACT BETWEEN MOISTURE AND C:N
- FOR WET MATERIALS MIX BASED ON MOISTURE
- FOR DRY MATERIALS MIX BASED ON C:N
EXAMPLE FOR POULTRY MANURE AND SAWDUST:
SYMBOLSEXAMPLE
a = POUNDS OF INGREDIENT a
PER POUND OF b: ?
M = DESIRED COMPOST
MOISTURE CONTENT50 %
ma = MOISTURE CONTENT OF
INGREDIENT a (SAWDUST)25 %
mb = MOISTURE CONTENT OF
INGREDIENT b (MANURE)70 %
R = DESIRED C:N OF COMPOST25:1
Ra = C:N OF INGREDIENT a500:1
Rb = C:N OF INGREDIENT b10:1
Na = % N OF INGREDIENT a0.11
Nb = % N OF INGREDIENT b6.00
MOISTURE CONTENT BALANCE
a= (mb-M) / (M-ma)
= (0.7-0.5) / (0.5-0.25)
= 0.2 /0.25
= 0.80 LB. SAWDUST / LB. MANURE
C:N BALANCE
a = (Nb/Na) x (R-Rb)/(Ra-R) x (1-mb)/(1-ma)
= (6.00/0.11) x (25-10)/(500-25) x (1-0.7)/1-0.25)
= 54.5 x 0.032 x 0.4
= 0.70 LB. SAWDUST / LB. MANURE
CONSIDERATIONS WHEN USING COMPOSTS
I. MATURITY
A. FRESH MATERIALS HAVE HIGH LEVELS OF
ORGANIC ACIDS
B. HIGH C:N CAUSES PLANT N DEFICIENCY
C. EVALUATE MATURITY
1. O2 CONTENT WITHIN PILE
2. RE-HEATING POTENTIAL OF MATERIAL
3. PRESENCE OF NITRATE
4. TIME
II. USE IN GARDENS OR FIELDS
A. USE ACCORDING TO SOIL TEST
1. ANALYZE FINISHED PRODUCT
2. MAY NEED TO SUPPLY OTHER NUTRIENTS OR LIME
B. COMPOST MAY HAVE TO SUPPLEMENT NUTRIENT PROGRAM
1. FRACTION OF TOTAL NUTRIENT ARE AVAILABLE
2. CROP AND SOIL DEPENDENT
3. DON'T EXCEED 50 TON/A (DRY BASIS)
C. APPLICATION METHOD
1. BROADCAST PRE-PLANT WITH STANDARD MANURE SPREADER
2. TOPDRESS LIGHTER RATES
3. FRONT-END LOADER AND GRADER LESS ACCURATE
III. USE AS CONTAINER OR POTTING MEDIA
A. QUALITY CRITICAL
1. PARTICLE SIZE, pH, SOLUBLE SALTS
B. EXAMPLE POTTING MIX
1. LIMIT TO 20-33 % COMPOST BY VOLUME
2. MIX EQUAL PARTS BY VOLUME WITH PEAT MOSS, VERMICULITE
OR PERLITE FOR VEG. TRANSPLANTS
3. MIX EQUAL PARTS BY VOLUME WITH COARSE SAND AND PEAT
MOSS FOR WOODY ORNAMENTALS
C. NUTRIENTS
1. AVOID FERTILIZATION FOR THE FIRST TWO WEEKS
2. TRACE ELEMENTS UNNECESSARY
OVERVIEW OF WINDROW COMPOSTING
I. FOUR COMPOSTING METHODS
A. PASSIVE
1. SIMPLE STACKING
2. MINIMAL MANAGEMENT
B. AERATED PILE
1. FORCED OR NATURAL AIR
2. NO TURNING
C. IN-VESSEL
1. CONFINED
2. BINS, SILOS, ROTATING DRUMS
3. HIGH MANAGEMENT
D. WINDROW => LONG, NARROW PILES THAT ARE TURNED REGULARLY
II. WINDROW CONSTRUCTION
A. SIZE
1. THREE TO NINE FT. HIGH
- LOW FOR DENSE MATERIAL,
HIGH FOR FLUFFY MATERIAL
2. 10 TO 20 FT. WIDE
- DEPENDS ON TURNING EQUIP.
B. AERATION
1. AERATE NATURALLY
2. MIX IS CRITICAL
C. TURNING EQUIPMENT
1. FRONT-END LOADER
- EXCHANGE INTERIOR WITH EXTERIOR
MATERIAL
- AVOID DRIVING ON PILE
- AVOID MIXING SOIL
- TURNS 20-70 CU. YD./HR.
- IRREGULAR PILE
2. WINDROW TURNER
- EXPENSIVE
- MAY REQUIRE > 80 HP TRACTOR
WITH CREEPER GEAR
- CONVERT OLD POTATO DIGGER OR
ROCK PICKER
- HIGH MAINTENANCE
- NEAT PILE
3. MANAGEMENT
- TURN REGULARLY
- MONITOR O2, TEMP., MOISTURE
- FREQUENCY OF TURNING DEPENDS
ON WINDROW AGE AND MATERIAL
- ODOR, LOW TEMP. ARE SIGNALS
- FLIES => TURN TO BREAK REPRO.
- MAY HAVE TO COMBINE PILES