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Above Ground Biomass Estimates at Saltonstall Ridge,
East Haven, CT. 1999



What is Biomass?

Aboveground biomass is all the plant material above the ground in a forest. That includes live trees, dead trees, branches, leaves and shrubs.

The plant life on earth is nature's storehouse of chemical resources and solar energy. This natural wealth is potentially a significant renewable energy resource. Estimating tree biomass is an important way to measure the energy potential of a forest. Biomass equations for individual trees are used to predict forest production and its relation to stand density, to compare biomass and production for individual trees species, and to estimate forest fuel potential.

To estimate the biomass found on Saltonstall Ridge, we applied biomass equations from "Biomass Equations for Sixty-Five North American Tree Species" published in Forest Ecology and Management (see below). The equations estimating biomass were developed by relating biomass to tree diameter at breast height (DBH) and other tree characteristics. Individual tree species often have more than one biomass equation due to the fact that the biomass equations were produced in several different geographical locations. Consequently, we had to use biomass equations developed at sites with different conditions than at our own site.

In "Biomass Equations for Sixty-Five North American Tree Species," the author suggests different approaches that researchers can take to minimize sample error:

  • find the geographically closest site
  • use several reported equations to estimate the range of biomass
  • generate biomass data using various published equations and fit a new equation to the generated data.


For the purposes of our study, we selected equations from the geographical regions closest to our sample area. In every case, we used the equation for total above ground biomass (AB). The majority of the biomass equations are in the form m=aD b, where m is the overdry weight biomass of the tree (kg), D is the dbh (cm) and a and b are parameters. The parameters a and b are different for every species. These formulas give reasonable estimates of above ground biomass based on tree species and dbh.


List of Biomass Equations 
How are Biomass Estimates Calculated?
Biomass Pie Chart for Dominant Trees

Biomass Estimates for 1991 vs. 1999
Estimated Biomass Based on Annual Tree Growth
DBH vs Biomass of Dominant Tree Species
Biomass Estimates for Dominant Tree Species

 Take a Look at Hubbard Brook

Ter-Mikaelian, Michael T. and Michael D. Korzukhin (1997), "Biomass equations for sixty-five North American Tree species", Forest Ecology and Management,1-24.

Biomass Page Design and Research: Michelle Broege and Jennifer Osha

Methods of Ecosystem Analysis | Site | Tree Rings | Phytosociology | Allometry | Chemistry | Biomass | Summary

Methods of Ecosystem Analysis
Date Last Modified: 4/12/99
F&ES 579B, Spring 1999