If that was the moment I measured then there is lean in the pole. Critical attention to the manual measuring process is a good thing, I'm better prepared to do a more accurate job next time.
Excellent photos, thanks John! -AJ John Eichholz wrote: > ENTS, > > I was a nice day, as usual when out in the woods. the tape drop > results were a surprise. I can add some more information about the > work we did. First, attached is a photo of the pole location at the > time of measurement. It is blurry, since I was using a 55mm lens. > The tip that the pole was at was the exact one I measured. From where > the photo was taken, the line of sight to the crown was about 57 > degrees. You can also make out Andrew as he leans out with the pole. > The top we measured was part of the main leader, which leans > uphill/downstream from the trunk. When the tape reached the ground, > it was perhaps 10' from the trunk due to the lean, and it did seem > pretty straight. I used a clinometer to sight level from the tape to > the upper point of the base. I got 137.9', and added 16' for the pole > adjustment and 2.2' for the distance from the upper base to midslope = > 156.1. Using the midpoint between the upper and lower base of the > tree allows the cbh readings to be accurately repeatable. > > I measured the tree from several locations, each time to the same tip > and to a pin located at 4.5'h. From each location my readings were > repeatable, but I did have a range of results: 158.4', 157.5' and > 156.3'. There is definitely some experimental error, especially with > such long baselines where the clinometer accuracy can have a greater > effect on the result. I would report the middle height, 157.5', in > this case. I suppose a 1.4' error is plausible in the tree, and > perhaps equally plausible in the ground-based measurements. Bob's and > my readings were remarkably consistent, using different instruments, > and using photos of the crown we were able to agree on the tip we > considered the highest. This might just be a case of maximum variance > between tape drop and laser method measurement. > > Bob reported on the sugar maple find already. Nearby that tree was > another, 120.2'h, in an area that seemed to have more maples than > average for the site. I also found two hemlocks over 119', one next > to the Thoreau Pine and one opposite the trail on the way out. There > is bound to be at least one more 120'+ hemlock somewhere in there. > > Here is a link to a couple more pictures of the climb: > http://s835.photobucket.com/albums/zz274/treetop314/ > Bart and Freddie, I can send you a CD of the rest of the photos if you > like. These are the best ones, though. > > John > > > On Fri, Dec 4, 2009 at 8:39 PM, <[email protected] > <mailto:[email protected]>> wrote: > > ENTS, > > Well today was a big day for the Massachusetts group of dedicated > Ents. At my request, Andrew Joslin and two companion We also > measured the Thoreau pine from as many locations as possible. Our > ground-based measurements ranged from 157.1 to 158.4 feet. John > and I thought the most probably height for the tree to be 158 feet. > > To cut to the chase, Andrew's tape drop came to 156.1 feet. John > and I were surprised, but that is the best measurement we have, so > the big tree is no longer in the 160 Club. However, John > established a new mid-slope baseline for girth using the Will > Blozan method. Thoreau's girth is an even 13.0 feet. So, the > Thoreau pine moves into another girth class. Lose some, win some. > > John went farther out the ridge while Andrew and team were getting > themselves positioned in the top of the pine. John measured a > sugar maple to 124.7 feet, a new height record for the Dunbar > Brook maples. The Rucker Index stands at 123.7 today. Its all time > high is 124.1. I found a tall ash upslope from Thoreau and the > Grandfather pine. Its dimensions are girth = 7.2 feet, height = > 128.9 feet. Not bad. I remeasured the Grandfather pine and got > 144.7 feet. That is a believable number, given Will Blozan's climb > a couple of years ago. I think he got around 143.5 feet or so. > > > > -- > Eastern Native Tree Society http://www.nativetreesociety.org > Send email to [email protected] > Visit this group at http://groups.google.com/group/entstrees?hl=en > To unsubscribe send email to [email protected] > > ------------------------------------------------------------------------ > -- Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected]
