2.2.2. Outlining the Process of Biomass Calculations The calculations began by describing typical forest operations currently being practiced across Washington state and then developing a harvest scenario matrix. Next, a management prescription was implemented, and the biomass volume as a byproduct of a forest operation determined, following Browne’s biomass equations. This volume of biomass was subjected to harvest configuration constraints to generate the volume reaching the roadside. The roadside volume was subjected to operability constraints, such as road limitations, to determine the potential market biomass. The potential market biomass was filtered through economic constraints, such as the cost to process and haul material to mills, to determine the volume of biomass that was delivered to a facility. The report begins to describe this process below starting with the forest operations that were studied. 2.2.3. Developing the Harvest Scenario Matrix The study team produced a scenario matrix that established the harvest activities utilized by logging operators, and included forest operations on pre-commercial thinning activities as requested by the scope of work. We used this matrix to develop the management scenarios used with the FVS models described previously. Table 2. Summary of harvest and forest operation scenarios
Harvest and Forest Operation Scenarios RH remnant stands >50 years RH remnant stands >65 years No PCT, RH @ 35 years No PCT, RH @ 45 years No PCT, RH @ 50 years No PCT, RH @ 55 years No PCT, RH @ 60 years No PCT, RH @ 65 years No PCT, RH @ 70 years No PCT, RH @ 75 years No PCT, RH @ 80 years RH @ 90 years No PCT, CT @ 25 years, RH @ 45 years No PCT, CT @ 30 years, RH @ 50 years No PCT, CT @ 35 years, RH @ 65 years No PCT, CT @ 40 years, RH @ 65 years No PCT, CT @ 45 years, RH @ 65 years No PCT, CT @ 55 years, RH @ 85 years CT or PC @ 55 years
Harvest and Forest Operation Scenarios PCT @ 6 years, RH @ 35 years PCT @ 12 years, RH @ 45 years PCT @ 15 years, RH @ 45 years PCT @ 15 years, RH @ 50 years PCT @ 15 years, RH @ 60 years PCT @ 15 years, RH @ 75 years PCT @ 17 years, RH @ 55 years PCT @ 15 years, CT @ 45 years, RH @ 65 years PCT @ 15 years, CT @ 55 years, RH @ 85 years PCT @ 20 years, PT @ 70 years - thinning from above and below
PC - from above and below PC - thinning from above and below PC - thinning from above & below w/RH @ 55 yrs PC - thinning from above & below w/RH @ 60 yrs PC - thinning from above & below w/RH @ 65 yrs PC - thinning from above & below w/RH @ 75 yrs PC @ 65 years - thinning from above and below PC @ 70 years - thinning from above and below PC @ 75 years - thinning from above and below Source: Study survey data (RH, regeneration harvest; PCT, precommercial thinning; CT, commercial thinning; PC, partial cut) Table 2 summarizes the harvest scenarios developed by the study team. The large number of alternatives was developed as requested by the contract to include various thinning options. While Washington Forest Biomass Assessment Report 2012/03/13
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