Estimating past diameters of Douglas-fir trees.

Abstract

Estimates of breast-height diameter outside bark for trees as of some previous date are required in certain kinds of forest growth studies. These past diameters may be found by subtracting total diameter growth from known present diameters, where total diameter growth is the sum of wood growth and bark growth. Wood growth is readily obtained by measuring the combined width of a given number of annual rings on cores extracted from trees. Bark growth, however, must be approached indirectly by some procedure like the one to be described.

Citation

Johnson, Floyd A. 1955. Estimating past diameters of Douglas-fir trees. Res. Note PNW-RN-112. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 4 p