The supply chain for feedstock crops used in biofuel production begins at a farm and ends at a biofuel refiner. Any entity within this supply chain that produces, processes, or takes ownership of reduced-CI crop or reduced-CI processed product must meet all applicable standards of this part. These entities include farms, first points of aggregation, intermediary entities, and biofuel refiners. If a biofuel refiner sources directly from a farm, the biofuel refiner is the first point of aggregation.

Crops produced using one or more CSA practices, in accordance with subpart F of this part, are referred to as CSA crops. Crops produced without the use of CSA practices are referred to as conventional crops. A farm producer may produce both CSA crops and conventional crops. CSA crops and conventional crops can be physically mixed. Crops that are sold with an associated reduced-CI, as compared to the national average CI, are referred to as reduced-CI crops. Reduced-CI crops may be composed of solely CSA crops or a combination of CSA crops and conventional crops. If CSA crops and conventional crops are produced at the same farm, the commingled crop must have an associated CI that reflects the proportion of CSA crops, quantified in accordance with subpart C of this part. Crops for which a reduced-CI may be quantified include:

(a) Field corn;

(b) Soybeans; and

(c) Sorghum.

CSA crops must be produced using one or more CSA practices:

(a) Field corn produced using no-till, reduced till, cover crops, nitrification inhibitors, split in-season nitrogen application, or no fall nitrogen application;

(b) Soybeans produced using no-till, reduced till, cover crops, or nitrification inhibitors; or

(c) Sorghum produced using no-till, reduced till, cover crops, nitrificiation inhibitors, or split in-season nitrogen application.