The mass of the biomass feedstock can be directly measured and converted to CO₂e using a default factor or direct measurements of biomass carbon and moisture content. The feedstock quantity can be checked for consistency against operational records, and will form the basis for estimating feedstock-related upstream emissions, as well as understanding the removal efficiency of the CDR process. In addition to characterizing carbon content, a feedstock sampling protocol should characterize embodied nutrients such as nitrogen, phosphorus, and potassium. This enables an assessment of potential nutrient depletion and may inform the estimation of upstream emissions. Any emissions associated with the process of biomass cultivation, procurement, and transportation must be included in the project’s lifecycle assessment.