Form Class (was -Re: Robinson State Park)   Fores-@aol.com   Nov 29, 2006 07:59 PST  Gary: The tulips sound like they are decent trees. Do you have any indication of the actual form class of the trees in terms of taper. For hemlock a form class of 67 is common for some of the ice cream cone tapered trees of New England but in WV a form class of 78 to 80 is common. For poplar in these parts young trees are figured in FC 80-82 with high quality large diameter, tall older trees close to a FC of 84 to 86. Russ Re: Robinson State Park   Gary A. Beluzo   Nov 29, 2006 09:42 PST  Russ Oh, okay, the Form Class is just the diameter inside the bark up at 16 feet divided by the DBH *100. One problem though, you need to cut the tree down and strip off the bark to do it! :-) Do you know of a similar ECOLOGICAL measurement(s) on the live tree? Maybe with the RDL 1000 or similar device one can get a good estimate of the Diameter at 16 feet (with the bark on of course). Gary Re: Robinson State Park   Fores-@aol.com   Nov 29, 2006 15:13 PST  Gary: The US Forest Service developed the volume charts years ago and they are currently getting reprinted by the USDA. From the definition of form class in the book this is how it is defined... "Form class is the percentage ratio between the diameter inside the bark at the top of the first 16' log and the diameter outside the bark at DBH (4 1/2 feet above the ground) For example, a tree with a first log scaling diameter 16" and a DBH of 20" the tree has a form class of (16/20 X 100) 80 The title of the book is "Tables for Estimating Board-Foot Volume of Timber" Last I knew it was available through some of the forestry supply companies and the USFS has a stock number of 001-001-00024-8/Catalog number A 13.2:T 48/17 I hope this helps. Russ Re: Robinson State Park   Fores-@aol.com   Nov 29, 2006 15:38 PST  Gary: Most of the time, I think it is generally assumed that as foresters we are looking at the actual taper of a standing tree.   For the purposes of ENTS types of measurements I think it would be appropriate for the measurements at both points outside the bark. In certain types of trees with large buttressed bases I think that form class measurements could prove meaningless.   However, I find it extremely useful in dealing with forest trees. The booklet I mention has standing tree volume tables in three forms, International 1/4" log rule, Doyle Log Rule and Scribner Decimal C Log Rule. The form classes in all three categories range from 65 to 90.   There is an average 2% increase in overall tree volume for each point increase in form class.    Form class is pretty much an industry standard and I think it could eventually become another cog in figuring Rucker indexes.    Because cubic calculations and volume documentation of extremely large trees is such an important part of the ENTS mission I would hope that some aspects of form class could prove useful. In all cases the volume tables do not cover trees with over 6 15' logs of 100' of merchantable wood. I have used form class many times in the past as a way to express extremes in quality or actual height. Russ Re: Robinson State Park   Gary A. Beluzo   Nov 29, 2006 16:57 PST  Russ, You got me thinking about tree measurements ("on the hoof") for ecological purposes and I did some Googling. I discovered some very interesting articles about folks that are experimenting with the use of a digital camera, laser rangefinder, calibration stick and photo imaging software for determining diameter and other metrics remotely. I'll provide a summary when I finish to this list. Soooooo...how about those Whately tulip poplars? Gary Re: Robinson State Park   Fores-@aol.com   Nov 29, 2006 17:33 PST  Gary: Have you ever used a Relaskop? Many of the timber company foresters that use tall species like yellow poplar use it because of the gauge that allows you to estimate diameters high up in the tree. A description of the beast is at... _http://www.benmeadows.com/search/relaskop/1299/_ I have permission to show them to anyone when I'm in the area. I talked to the owner of the Whately poplars a few months back and they are still there and growing. Maybe we can down there next time I'm in the area. Russ Re: Hemlocks at MTSF RETICLE???   Gary A. Beluzo   Nov 30, 2006 05:34 PST  Hi Will, I am interested in Jess's program. I am researching methods that utilize a digital camera this week, there are many that work really well. Also I have found some equations for approximating above ground and below ground biomass. Any computer or digitally based analyses that folks have I would be interested in reviewing. Especially anything that could interface with ArcGIS potentially. Is anyone using ArcPad out there in ENTSland? Gary On 11/29/06, Will Blozan wrote:   Dale, Have you measured any Cook Forest hemlocks yet for volume? It would be great to get some numbers. Jess has developed an interpolator for monocular measurements that uses only two distance measurements. It is very sweet and really speeds things up- provided the trunk is straight. I can send you the program if you want. Will   Home