Thursday, April 3, 2008

Virginia Forest Type Map 1940

In 1940 the US Forest Service conducted the first systematic forest survey in Virginia. Survey crews put in over 31,000 ¼-acre plots spaced at 10 chains along cruise lines 10 miles apart. The data collected were used to produce tabular summaries of forest conditions and stocking. The data were also used to produce a general forest type map.

The old map is printed in green and white on an 8-1/2 by 11 inch page and is difficult to read. To create a more informative map, I scanned the original map, geo-registered it with the 2000 Census County map, and created a modern GIS vector dataset. I feel this map is much easier to use.

One of the interesting things to note are the distributions of the pine-hardwood types (loblolly-hardwood, Virginia pine-hardwood, shortleaf pine-hardwood, shortleaf – pitch pine-hardwood, and white pine-hardwood). Keep in mind that the definition of pine-hardwood stands include any stand with 25% or greater pine volume.
Click on map for a bigger image:

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