Welcome to our interactive
Hubbard Brook landscape Biomass program!

This program calculates forest biomass and nutrient estimates by species and plant part at Hubbard Brook, online and on the fly!!  The calculations are for Watershed 6, the undisturbed biogeochemical reference watershed for which we have forest data starting in 1965. Biomass, productivity and nutrients can be estimated over the entire watershed or selected plots.

Please do not use any of these numbers in any official way without first checking with the Hubbard Brook research team.

If you are losing the page when reloading images in the calculators, please go back to the W6 front page and reenter by clicking "click here if your browser does not support frames".

This program is optimized for Internet Explorer 6.

Watershed 6

Please choose a year:
Please choose a health code (vigor):
Please choose a size class:

You may select a diameter range over which you would like to make the summaries. This will supercede any decision you may have made above for size class. The smallest diameter included in the data is 2 cm and there are no trees over 120 cm dbh. (Note that all trees 2.0 to 2.4 and 10.0 to 10.4 will be doubled, and all trees 9.5 to 9.9 will be excluded. See explanation. We recommend using either integers (except 10) or a midpoint range (i.e. X.5 to X.4), unless you have read all the notes and understand exactly what the program returns.)
Enter lower diameter (in cm): 
Enter upper diameter (in cm): 

Please indicate by number which of the following plot summary options you are going to use:

1. Please choose one of our standard vegetation zones: 

2. OR, choose individual plots (hold down the shift key to select large blocks of plots or hold down the Ctrl key to select several individual plots):
                click here for a plot map

3. OR, enter a lower and upper elevation limit (in meters). The elevation range for Watershed 6 is 550 to 792 m. (Please left justify and leave one space between the numbers, e.g. 600 700):

4. OR, enter a single plot. Plots in Watershed 6 are numbered 1 to 208:

5. OR, enter the numbers of the first and last plots in a sequence (please left justify and leave one space between the numbers, e.g. 23 48):
Note: If you want summaries for the standard "thirds" (or "sub-areas") of Watershed 6 as published in several papers, use 1 to 86 for the upper third, 87 to 158 for the middle third, and 159 to 208 for the lower third.

Do you want to estimate productivity? 
Note:  Productivity can only be estimated for the 1997 forest inventory because that is the only point in time, so far, for which we have extensive tree ring data on which to base calculation of productivity. This option will not run for dead trees.

Just for fun, increase tree growth by some percentage (e.g. 5) and see what happens.  This will make the annual ring widths used in the productivity wider by the percent you have chosen. (For example, if the ring width was 2 mm and you want to increase it by 5%, the new ring width would be 2.1 mm.): 

Would you like to see a summary of chemistry? 
Please choose an element:  

Would you also like to see plot by plot chemistry data for the species selected below? (default is all species combined)

Would you like to see a watershed map and plot by plot biomass data? (this may take some extra time)

Please choose the species you would like to map:

Please choose the plant part you would like to map: 

Only those trees within the size and vigor classes and plots selected above will be considered in the calculations. 



Click here for the general overview and details of how all these calculations are being made.

Click here for Tom's very specific miscellaneous notes regarding this calculator.

Click here to access the data used in these calculations.

        Please note that this page may undergo changes in the future as we develop new ideas for calculating phytosociology. In the meantime, we welcome any suggestions that you may have for this page at thomas.siccama@yale.edu.

[ biomass page | stop 7 | trail map | W6 front page | main HBES homepage ]

Web page created May 2004
by Thomas Siccama and Ellen Denny