Opportunities for NTS

General discussions of measurement techniques and the results of testing of techniques and equipment.

Moderators: edfrank, dbhguru

Post Reply
User avatar
dbhguru
Posts: 4526
Joined: Mon Mar 08, 2010 9:34 pm

Opportunities for NTS

Post by dbhguru » Wed Sep 05, 2018 6:57 pm

Ents,

Today Dr. William Moomaw, Ray Asselin and I met with officials from Mass DCR, TNC, a representative from University of Vermont, and Harvard Forest on establishing monitoring projects for the State's forest reserves as part of the function of the DCR Forest Reserves Scientific Advisory Committee, which I chair. All went well. One of the DCR attendees is their forest biometrician, a very knowledgeable, competent person.

One of our first projects will be to tighten standard allometric equations (or develop new ones) to fit the trunk forms of several of the tree species common Massachusetts, comparing those forms when young, in early maturity, and late maturity, with heavy emphasis on the latter. Our results will feed a shared database being developed at UVM. Of course, one species high on our beginning list is the white pine. Our work will be used in ground-truthing terrestrial LIDAR modeling being developed by UMASS Boston and Harvard Forest. Woods Hole Research Center will almost certainly become involved, at least peripherally in their satellite-based forest carbon modeling project.A gain, our role will be ground-truthing.

There's no reason not to extend our efforts to the whole Northeast. Our study sites can be far and wide. So, if some of you would like to participate in the project, which involves volume modeling selected species from youth to senescence, please let me know and we will find a place for you.

This is an opportunity for NTS members to become involved in some pretty heady stuff.

Bob
Robert T. Leverett
Co-founder, Native Native Tree Society
Co-founder and President
Friends of Mohawk Trail State Forest
Co-founder, National Cadre

User avatar
JHarkness
Posts: 249
Joined: Sun May 13, 2018 5:44 pm

Re: Opportunities for NTS

Post by JHarkness » Thu Sep 06, 2018 4:14 pm

Bob,

I'd love to be a part of this, though I'm not sure how much help I could be. I don't have a reticled monocular as of yet so volume measurement would be substantially harder, and probably not as accurate, as it would be with one, but I have come up with a way of volume measurement with a rangefinder alone, it seems accurate so far but I haven't had the opportunity to do any extensive tests of it on forest grown trees yet, this fall I'll begin doing this on some of my trees, if the results seem accurate and reliable I'll run it by a few people with ENTS to hear some thoughts on the method, not as a replacement for the current method, but just as an alternative method. That said, I am thinking of picking up a reticled monocular soon, what brands/models would you recommend for volume measurements?

I have thought of doing volume measurement of several species occurring on my property, the white ashes and sugar maples come to mind, red oak as well but I only have one very old oak and it doesn't really represent what a red oak of the same age is capable of in a warmer and more protected environment. The great white pines, hemlocks and ancient white cedars of the Adirondacks come to mind as other interesting trees to incorporate into this, I've seen some truly massive old growth hemlocks in the Adirondacks, one huge tree I found was probably close to 12' CBH and had almost no taper, it's top had been broken at some point (by top I mean probably more than half it's trunk), it happened so long ago that the fallen piece of it's trunk had completely rotted away. Despite this injury, it still stood as tall as the surrounding mature maples, cherries, spruces and remaining beeches. Measuring the volume of trees such as this would be exceptionally interesting, I feel. That hemlocks on that trip were incredible, I saw some absolute monsters, many snags, many live trees with broken tops. I came across a site where a huge stand of old growth hemlocks had been logged sometime in the '80s or 90's, some of the stumps must have been close to five feet in diameter.


Joshua
"Be not simply good; be good for something." Henry David Thoreau

User avatar
Don
Posts: 1569
Joined: Tue Mar 09, 2010 12:42 am

Attention !!! Opportunities for NTS nerds : ~ }

Post by Don » Fri Sep 07, 2018 2:53 pm

Joshua-
Your willingness to volunteer, I hope, encourages others to follow your lead.
With regard to reticled monoculars, I have found reasonable options among several discount houses and managed to make really inexpensive modifications to the one I got (Vortex Solo R/T 8x36 [with Ranging Reticle]).
For a start (I stalked mine for awhile, to get a sense of what a good deal is), familiarize yourself with their web page (http://www.ents-bbs.org/viewtopic.php?f ... 7&start=10) where you'll see options to view reader reviews, similar products and more, including the website price of $160. With diligent searching you can approach $100 for new ones, but be careful to be specific in your searches (make sure you get the 8 x 36 model, with the R/T designation (Ranging reTicle). Cheaper, used ones can be had at eBay, at your own risk, but with significant savings.
Vortex used to be about the only one in the game, but a new (to us) one has emerged from Bushnell, and I'll let Bob introduce you to GIZMO, his Bushnell Legend Ultra HD 10x42 Monocular, Mil-Hash Reticle, 4.2mm Exit Pupil. I've yet to view the world through it yet, but its specs stand up to scrutiny, and it's field use and prowess has earned Bob's highest accolades. Cost is more, but with stalking prowess....

Something to mention...either of these are superb for multiple purposes in the woods, for hunters, for birders, for golfers and many others. The Bushnell, according to Bob, is a superb light gathering machine, and is a pleasure to have, comes with tripod attaching capabilities, and can provide phenomenal results, pretty much out of the box.

For basic philosophical comments, and more researching, do a Google Search on:
vortex solo "www ents bbs org".

For modifying the Vortex Solo R/T's pocket clip, to make it tripod compatible, see my $7 solution below:
JB Weld...
JB Weld...

Or search at:
JB Weld vortex solo R/T "Native Tree Society".

-Don
Don Bertolette - President/Moderator, WNTS BBS
Restoration Forester (Retired)
Science Center
Grand Canyon National Park

BJCP Apprentice Beer Judge

View my Alaska Big Tree List Webpage at:
http://www.akbigtreelist.org

User avatar
Erik Danielsen
Posts: 875
Joined: Mon Mar 17, 2014 5:46 pm

Re: Opportunities for NTS

Post by Erik Danielsen » Fri Sep 07, 2018 7:36 pm

Josh, to follow up on what Don said, the Vortex Solo usually seems to go for 110-120 new... I bargain shop used for most gear, but for the Vortex it seemed pretty reasonable. It's been a great tool to use.

Bob, consider me on board. I'm plugging away at a few sites, but would be very open to focusing on particular species or methodologies to help this project along. Locally there is an opportunity I'm pursuing to examine volume growth in some established dbh plots, to look directly at the question- even if we've now made it clear that individually, large old trees grow in mass at greater rates than "youthful" trees rather than being stagnant, is it the fewer big trees or the more numerous younger trees that do most of the sequestration in an actual forest? I think many of us here are in a position to make some educated guesses, but data will hopefully be on the way. At first just modeling each tree in the plot sufficiently that each gets its own allometric equation, to then be applied retrospectively to the dbh changes that have been tracked until now. Form factor should not have changed significantly in the several years tracked so far, and future rates of change in form factor can be assessed from whatever we establish now. Just one more way to put these tools to work!

User avatar
dbhguru
Posts: 4526
Joined: Mon Mar 08, 2010 9:34 pm

Re: Opportunities for NTS

Post by dbhguru » Sat Sep 08, 2018 4:46 pm

Erik,

I like the way you talk. And thanks, I was confident that both you and Elijah were on board. And you are absolutely on point. We need to understand the tradeoffs between fewer larger trees and more smaller ones for different stand compositions. It is a no-brainer. There are probably principles at play. Maybe we can contribute to their discovery in situations where our kind of measurements expertise can play a role.

I recently ran 21 trials of measuring internal points to the frustums for three young hemlocks. I used Sparky and Gizmo. For the frustums, at the 21 internal points, the theoretical diameter was calculated based on a cone. A comparison was then made between theoretical and reticle-measured. The average difference was a mere 0.26 inches. Yes, inches, not feet. Can't get more conical than that, but then I've always seen young hemlocks as having conical tapers. If we can apply the conical form to let's say a quarter or half acre of young hemlocks growing in close proximity to one another, we can calculate total volume and carbon amount without having to take a ton of reticle measurements. The more we can model each species across seedling, sapling, pole-size, mature, and old-growth stages, the more important our role in ground-troothing for the heavyweight scientists engaged in working on landscape models.

I've also begun a more intensive testing of the expected error for reticle measurements resulting from errors in the input variables. One value that's usually taken for granted is the manufacturer's reticle factor. See below.
Reticle Factor 2018-09-08 at 4.32.20 PM.png
Bob
Robert T. Leverett
Co-founder, Native Native Tree Society
Co-founder and President
Friends of Mohawk Trail State Forest
Co-founder, National Cadre

User avatar
Don
Posts: 1569
Joined: Tue Mar 09, 2010 12:42 am

Re: Opportunities for NTS

Post by Don » Mon Sep 10, 2018 4:04 pm

Bob
With only one sample on the Bushnell, it's hard to know if they're all going to be 1020 + or -, so your spreadsheet set up is a good idea. Same probably goes for the Vortex Solo too, although it's gradations aren't as precise as the Bushnell's ?
Don
Don Bertolette - President/Moderator, WNTS BBS
Restoration Forester (Retired)
Science Center
Grand Canyon National Park

BJCP Apprentice Beer Judge

View my Alaska Big Tree List Webpage at:
http://www.akbigtreelist.org

Post Reply

Return to “Measurement and Dendromorphometry”