Massachusetts Forest Impacts if Proposed Biomass Incinerators Are Allowed
scenario 1scenario 2land use datacalculations

Chris Matera, P.E., and Ellen Moyer, Ph.D, P.E.
GIS analysis and programming by Gordon Green

The animations add the demand for wood for 5 proposed biomass incinerators in Massachusetts to the current wood demand, which is mainly for lumber and cord wood.  The animations demonstrate the land area in western and central Massachusetts that would be required to be logged to satisfy the total demand for these 5 plants which would add only about 1 percent to Massachusetts' electrical generating capacity (see calculations below).

Land area logged is based on the current logging intensity of 19 green tons/acre logged (see calculations).  Current logging intensity includes methods ranging from sustainable to clear-cutting.  For photographic evidence of extensive clear-cutting on State-owned public land that has occurred recently, see

The first scenario above removes the following forests from availability for biomass harvesting:  rare species habitat, scenic landscapes, public “protected” land, and other protected open space.  There are variations in either direction inherent in this approximation; some excluded land may in fact be logged (e.g., privately owned protected land), and some included land may in fact not be logged (e.g., residential lots).

This scenario demonstrates that all land available for logging in central and western Massachusetts, as defined, would be logged in only 9 years.  The required logging to fuel the proposed biomass incinerators clearly is not sustainable, since trees take much longer than 9 years to grow back and the negative impacts on the forest ecosystem would be massive.

The second scenario represents the extreme case where all forested land in central and western Massachusetts would be made available for biomass cutting - including rare species habitat, scenic landscapes, public “protected” land, and other protected open space.  In this case, all forested land in central and western Massachusetts would be logged in only 16 years.

Land Use Data (return to top).

Forest consists of polygons that are classified as Land Use Code 3 from the Massachusetts Geographic Information System (MassGIS) Land Use (2005) (June 2009) datalayer. According to the datalayer description, forested areas are "Areas where tree canopy covers at least 50% of the land. Both coniferous and deciduous forests belong to this class." Note that this includes any land with tree cover, which may or may not be suitable for logging (4,533.60 square miles total).

Priority Habitat includes polygons from the MassGIS NHESP Priority Habitats of Rare Species (October 2008) datalayer. According to the datalayer description, "Priority Habitat polygons are the filing trigger for project proponents, municipalities, and all others for determining whether or not a proposed project or activity must be reviewed by the NHESP for compliance with the Massachusetts Endangered Species Act (MESA) and its implementing regulations." (NHESP is the Natural Heritage & Endangered Species Program.)

Scenic Landscapes is the MassGIS Scenic Landscapes (July 1999) datalayer, which, "...depicts areas identified as part of the Massachusetts Landscape Inventory Project, Department of Conservation and Recreation (then DEM), 1981." (from the MassGIS Scenic Landscapes datalayer description).

Other Protected Land is derived from the MassGIS Protected and Recreational OpenSpace (July 2009) datalayer, consisting of polygons where owner_type is other than governmental, including "P" and “N” for private and non-profit. According to the MassGIS datalayer description, "The protected and recreational open space datalayer contains the boundaries of conservation lands and outdoor recreational facilities in Massachusetts."

Government-Owned Protected Land is derived from the MassGIS Protected and Recreational OpenSpace (July 2009) datalayer, consisting of polygons where owner_type is "S", "F", "C", or "M", for state, federal, county, and municipal government entities.

Animation Production

Datalayers were converted to rasters with each pixel representing .01 square miles. Raster intersections were calculated using the ESRI ArcGIS raster calculator. The simulation was created by summing the areas of pixels near each incinerator location until the sum was equal to or greater than the projected annual requirements of each incinerator.

Calculations (return to top).

Current Logging

First, current conditions are evaluated, before any new large biomass incinerators are built in Massachusetts.  The current total annual timber harvest (total green tons) and logging intensity (average green tons harvested per acre logged) are calculated. 

Timber harvests larger than 25 thousand board-feet (mbf) or 50 cords are recorded by the Massachusetts Department of Conservation and Recreation (DCR).  Harvests, not including tops and branches, are reported using various units – acres, mbf, or cords – and the land area logged is also recorded.  (Source: DCR, 2005 Annual Stakeholder Report: Promoting Stewardship of Our Forests for a Safe and Healthy Environment, Economy, and Society, pages 10 and 15.)

Average Annual Massachusetts Timber Harvest (2001-2005 period):

  • Private Forests:           27,561 acres    62,604 mbf      44,806 cords   20,088 green tons
  • Public Forests:             1,417 acres     5,487 mbf        3,757 cords    2,425 green tons
  • Total:                     28,978 acres    68,091 mbf      48,563 cords   22,513 green tons

Convert harvests reported in mbf or cords to green tons using the following conversion factors (Burlington Electric): 

1 mbf = 2 cords                         1 cord = 2.5 green tons                     1 mbf = 5 green tons

Tree tops and branches that would be part of biomass incinerator fuel need to be added to the harvest numbers above, using Massachusetts Department of Energy Resources information ( Biomass Availability Analysis - Five Counties of Western Massachusetts, page 13):  A total of 29% additional mass is in tops and branches.  Use 50% for forest biomass and leave 50% to replenish forest floor, therefore need to add 14.5% to the reported timber harvest.

The total average annual Massachusetts timber harvest, including tops and branches is then:

Total = [68,091 (5) + 48,563 (2.5) + 22,513] x 1.145 = 554,610 green tons

Typical logging intensity = 554,610 green tons / 28,978 acres = 19 green tons per acre

Proposed Logging

Next, the additional demand that would be exerted by the proposed biomass incinerators is estimated.  The calculation does not include the existing 17 megawatt (MW) biomass incinerator (Pinetree) in Westminster since its demand is currently being met and any supply from Massachusetts is covered under the current logging calculation.  Power reported by the biomass incinerator developers in MW is multiplied by 13,000 green tons/MW (DCR, Biomass Availability Analysis – Five Counties of Western Massachusetts Renewable Biomass from the Forests of Massachusetts, page 11.)

The biomass incinerators propose to burn a combination of forest biomass and “waste wood” that includes tree tops and branches, sawmill residue, land clearing, pallets, and the woody fraction of construction and demolition (C&D) debris.  Available waste wood is subtracted from the total increase in demand for wood to calculate the forest biomass needed.  In addition, the biomass incinerator in Springfield proposes to burn mostly C&D wood, and only approximately 25% forest biomass, therefore its forest biomass demand is reduced accordingly. 

Megawatts Powered by Forest Biomass + “Waste Wood”













Forest Biomass + “Waste Wood” Needed for Proposed Incinerators

Wood Demand = 190 MW x 13,000 green tons/MW = 2,470,000 green tons

Forest Biomass Needed for Proposed Incinerators

Need to subtract out available “waste wood” from total wood needed for fuel.  In-state reported available "waste" wood of 629,000 green tons is accounted for ( Biomass Availability Analysis - Five Counties of Western Massachusetts, page 31).

Forest Biomass Demand = 2,470,000 – 629,000 = 1,841,000 green tons

Current Plus Proposed Logging

Total Forest Biomass Demand = 554,610 + 1,841,000 = 2,395,610 green tons

Required Annual Acreage Proposed to Be Logged

The total area that would need to be logged each year is calculated by dividing the total demand by the current logging intensity of 19 green tons/acre. 

Total Annual Cut = 2,395,610 green tons/19 green tons/acres = 126,085 acres

= 197 square miles

Total Annual Cut Weighted Distribution Around Each Incinerator

The annual acreage that would need to be logged around each incinerator shown on the animations is proportionate to its power generation.  The Springfield incinerator proposes to burn approximately 75% C&D wood, therefore 75% of the MW (28 MW) for the Springfield incinerator is excluded from the calculation.


126,085 *15/(190-28) = 11,675 acres 


126,085* 47/(190-28) = 36,580 acres


126,085 * 40/(190-28) = 31,132 acres


126,085 * 50/(190-28) = 38,915 acres


126,085 * (38-28)/(190-28) = 7,783 acres

Forest Power Generating Capacity Increase

Total 2007 generating capacity = 13,557 MW ( US Government Energy Information Association)

Capacity Increase = 190 / 13,557 = 1.4%