Posted: Sun Mar 26, 2017 9:09 am
by dbhguru

This is more appropriately an American Forests National Cadre topic, but improved tree-measuring for sport has a place in the "Measurement and Dendromorphometry" topic.

Don Bertolette and I are moving on with plans to offer long distance learning for Cadre apprentices. The concept is Don's idea. He has served the cause well as a visionary.

We're are now experimenting with ways to put the concept into practice, and we have a route forward. The Texas state champion tree coordinator and two of her foresters have asked to sign on as apprentices, and that is a major coup. Don had been working to bring them aboard for quite some time. Mission accomplished.

My part is to come up with program materials: diagrams, formulas, problem sets, etc. We already have a huge amount of material that we've presented in piecemeal fashions to others in the past, but these materials need better organization and a good field testing. The Texas folks will serve as a testing ground.

A continuing challenge for us is how to best explain the weaknesses of the primary tree-height measuring method that has been in use for decades, what we define as the Tangent Method in the American Forests Tree-measuring Guidelines handbook. Over the years, I've spent a lot of time drawing diagram and presenting mathematical arguments to help long time users of the method understand its major flaw. That flaw stems from how the method is applied as explained in the simple instructions often accompanying clinometers as supplied by the manufacturers. However, my approach has often intimidated measurers who may not have cracked a math book in years. So, I've been looking for ways to visually portray the problem with the Tangent Method when used on trees that don't have their tops vertically positioned over their bases. The following diagram is a step in that direction. Don has given it his blessing, but we are alway opened to improvements. Ideas, thoughts?

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