A fully constructed band dendrometer. (Credit: SERC Staff)

Final notes

Some cautions

If the gap width increases to more than the size of the window, it will be impossible to measure the gap width. This can happen if the tree is growing very rapidly or if the band has been on the tree for many seasons. If you suspect at the beginning of a year's measurements that this might happen, install another band above or below the first and make measurements on both bands.  For analysis, keep the series that has the complete series of measurements for the year - from before growth begins until after growth ends.

Sometimes a band may become stuck - the gap width is not changing with growth in circumference. This can happen on smaller trees with smooth bark.  In most cases the band will become unstuck by itself, but you can often free the band by lifting it briefly from the tree. Make another measurement after doing this and make a note of the adjustment.

What now?

Learn about suggestions for using dendrometer gap width measurements: What to Do With the Measurements of Gap Width

References

Keeland, B.D. and P. J. Young. 2007. Construction and installation of dendrometer bands for periodic tree-growth measurements. U.S. Department of the Interior and U.S. Geological Survey. View the archived web page (as of 23 January 2023).

Supplies for Manual Band Dendrometer Construction/Installation

Punch tool for making the spring holes: 
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Heavy-duty shears for cutting the band material are available from many sources, for example:
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Digital calipers, resolution of 0.01 mm and suitable for the majority of conditions, are available from many sources, for example:  (Note: There are more robust kinds for measurements in cold and under high humidity, but they are much more expensive.)
View product on Global Industrial

Band material (½" wide stainless-steel banding, called 'steel embossing tape')
View product on Grainger

Stainless-steel extension springs - these are long-lasting and weatherproof and can be stretched to more than double their length.  We mainly use the 3 inch long springs (model LE026C 11S) but for smaller trees the ones that are 1.5 inch long (model LE026C 07S) are a better fit
View product on Lee Spring