IAMP-Biochar Application Practice
(within NRCS Codes 336 & 808)
Description
Biochar is a carbon rich material obtained through partial combustion of biomass, typically cropped
residues, manure, or forest slag. Biochar can be applied as a soil amendment to raise soil pH,
reduce nitrogen leaching, and increase water holding capacity. It can also be incorporated into
soils to increase carbon sequestration. See NRCS Soil Carbon Amendment practices (Code 336 or 808).
Benefits
Biochar helps to buffer soil pH with associated nutrient availability benefits. Biochar contains
some mineral nutrients in addition to carbon. It has high cation exchange capacity. It can improve
soil structure. It can absorb some contaminants of soil. It increases soil moisture retention,
potentially minimizing leaching losses and possibly increasing crop yields.
Soil Carbon Impacts
As a soil adjuvant biochar directly incorporates carbon in a relatively stable form into soil.
Greenhouse Gas (GHG) Impacts
Typically, the fuel source for biochar would otherwise decompose, releasing CO2 into the
atmosphere, so biochar provides a method for carbon capture.
Considerations for Success
- Biochar applications may not improve crop performance or yield as anticipated.
- Costs associated with the higher application rates may be substantial and well above incentive
payments.
- Recommend mixing biochar to a depth of 6 to 12 inches following field application.
- Not all biochar is the same and therefore needs to be tested to understand the characteristics
of the biochar.
- It is possible that the biochar results in net nutrient retention and possible nutrient stress.
Mixing or conditioning biochar with compost or other nutrients can minimize the risk of nutrient
stress, particularly phosphorus stress.
IAMP Preferences/Considerations
The IAMP project incentivizes practices that result in a net reduction in GHG and increase in soil
carbon. Biochar, whether procured or produced on-farm, provides a potential GHG savings over BAU.
GHG savings from biochar can be estimated relative to CO2 emissions that would be emitted
by the
unprocessed biochar feedstock. One IAMP partner, the Coeur d'Alene Tribe, will be manufacturing
biochar on its Tribal lands to document the cost of production. The Coeur d'Alene Tribe will also
apply biochar to a demonstration site to test its effectiveness for improving crop production. Other
IAMP participants may elect to implement biochar depending on availability and costs. Depending on
those costs, IAMP incentives may only offset rather than fully cover the costs of biochar
application. IAMP is investigating biochar sources suitable for the project and producers should
consult with an IAMP representative for the status of those sources. Other benefits of biochar can
be considered as additional to CO2 mitigation accruing to the producer.
Specific Details
IAMP has several requirements to document the biochar practice was implemented correctly and to
document the effectiveness of the practice from the current cropping strategies employed in the
field. The cost of analysis of any required soil, crop, biomass, or Biochar sampling and analysis
will be covered by the IAMP project. For an overview of all required sampling for each IAMP
practice, see IAMP required sampling. Implementing partners will be
assisting with the collection of any sampling related to the practice. Each of these requirements is
described below.
-
Baseline strip:
Producers will maintain a minimum strip of 80 ft in length and a minimum width of 20 ft where
the full baseline synthetic fertilizer rate will be applied as a comparison to the rest of the
field. The actual dimensions of the strip can vary to be compatible with the width of implements
used to manage the field.
-
Soil Carbon sampling:
Paired soil sampling points in the baseline strip and in the treated field at the start of the
project and at the end of the project is required to track the changes in soil carbon over the
duration of the project, see the IAMP Soil Sampling Protocol.
-
Soil Nutrient sampling:
Paired soil sampling points in the baseline strip and in the treated field prior to planting and
after harvest every ft down to 3 ft is required (down to 5 ft is preferred) to set fertilizer
rates, assess the impacts of the practice on available soil nitrogen, and identify any nutrient
deficiencies/benefits from the implemented practice, see the IAMP Soil Sampling Protocol.
-
Crop Biomass sampling:
Paired above ground crop biomass measurements at the paired soil sampling locations will be
required prior to harvest and will be evaluated for total dry biomass weight as well as the
percent carbon and nitrogen, see the IAMP Crop Biomass Sampling Protocol.
-
Biochar sampling:
A biochar sample will be sent in for analysis prior to application each year, see IAMP required sampling for information on where to send the sample.
Specifically the biochar analysis must include the following information.
-
Use biochar that is produced by heating biomass to a temperature in excess of 350°C
under conditions of controlled and limited oxidant concentrations to prevent combustion
(pyrolysis or gasification).
-
Biochar analysis must report:
- Country of origin of biochar and feedstock, and feedstock composition.
- Production method (e.g. verification of temperature and limited oxygen
conditions).
- Organic carbon, ash, nitrogen, pH, EC, liming equivalent, phosphorus, potassium,
and pH of the final material.
- Use laboratories successfully meeting the requirements and performance standards
of the International Biochar Initiative (IBI) Seal or use an alternative NRCS-
or State-approved certification program that considers laboratory performance
and proficiency to assure accuracy of laboratory analyses.
-
Do not use biochar produced from:
- Crop residues that could otherwise be left on the field to provide soil
protection and improve soil organism habitat, or
- Woody residue needed to sustain forest health and wildlife habitat referenced in
NRCS CPS Forest Stand Improvement (Code 666).
-
Grower supplied field management information:
- Crop yield maps (if available for both the baseline strip and the remaining field).
Criteria/Verification
Inspection by implementing partner. Both Tier 1 and Tier 2 growers will provide a record of the
biochar application rate and timing, source of the biochar, and specific characteristics of the
biochar provided by the supplier.
Incentive Payments
$60/acre in the year of application.
Stacking or Companion Practices
Biochar amendments are compatible with other incentivized IAMP practices. Cover crops, Conservation
crop rotation (>2 crops), Intercropping, No tillage from conventional, Reduced tillage from
conventional, Nutrient management, Prescribed grazing, other Soil carbon amendment.