Interesting challenge.
One thing that might be interesting to check is comparing the distance from Point A to Point B along your centerline against the as-the-crow-flies distance.
Tons of false positives & negatives, but it might yield some interesting results, all the same.
If you have a polygon dataset of that forest coverage, you could also experiment with how these lines of measurement intersect or don't intersect the forest.
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M Reed
"The pessimist may be right oftener than the optimist, but the optimist has more fun, and neither can stop the march of events anyhow." — Robert A. Heinlein, in Time Enough for Love
