Height density analysis and Historical documentation Gary A. Beluzo Jun 06, 2005 10:16 PDT
 Bob and John: Do you have any geocoordinates or I wonder if we should come up with a standardized FIELD SHEET which has room to sketch relative positions and labels of trees on some sort of grid? Perhaps on a simple grid data sheet you could pencil in the approximate location of individual trees and write in the dendromorphometry. Has anyone in ENTS come up with such a standardized worksheet? Gary
 RE: Height density analysis and Historical documentation Robert Leverett Jun 06, 2005 13:09 PDT
 Gary:    I've been piddling around with a worksheet format. John and I discussed a simple method of getting the azimuth of each tree in a plot using my new tripod that has a level and a scale in degrees. I can sight on a tree and read the angle much easier than I can read a compass. For the next plot, we'll try to put it all together. The complete process as we envision it is to:    1. Locate the center of the plot and set up the tripod.    2. Put a small tag on each tree to be measured.    3. Position one person at the center to do the recording and directing of one or more measurers to the trees.    4. As a tree is measured, the tag is removed. The recorder would measure the distance to the tree and its azimuth and record the species.    5. The measurer would measure girth and height or height class and call back the numbers. The measurer would also select the age class.    6. The measurer could also provide other data such as condition.    I suspect that collecting all these data elements for a half acre plot will require between 1.75 and 2.5 hours. Despite the work, plots established with this amount of data should prove very worthwhile for us in the long run. We would likely measure all trees above a height threshold very accurately. For instance, in the Bullard Woods plot, we measured the tallest trees by employing our usual methodology. That is how we got the 115.3-foot (115.5 by John's calcs) shagbark hickory identified as the tallest in our plot.     I can identify approximate GPS coordinates from a terrain map. We might come even closer using that new aerial photography system. Bob
 RE: Height density analysis and Historical documentation Gary A. Beluzo Jun 07, 2005 05:13 PDT
 Hi Bob: This proposed method seems doable in the field and applying it to many sites will be more practical than the INTERPOINT method. I think we all realize that determining the GPS coordinates for each tree in a plot is just not accurate enough with most of the handhelds and simply takes too long with a device like a Trimble Geoexplorer. However, if you set up your tripod as the plot center and record GPS coordinates over a 10-15 minute period we'll have a good "bench mark" from which we can re-create the locations of the trees in the GIS from the azimuth/distance measurements as long as they are fairly precise (0.1 degree and 1 cm, respectively). I am generating raster grids (cell size 30m, 15m, and 5m)from the MASSGIS DTM (digital terrain model) files for MTSF. I've started with Mohawk because so much field work has already been done out there and ground-truthing the images will be easier. Once we know which cell size we need to use I can produce raster images for all of our OG sites. From the raster images we can derive slope, slope position, aspect, TSI, LFI, and various hydrologic values (e.g. flow direction and accumulation) for each pixel in any location in Massachusetts. The more of the primary literature I delve into the more I realize that terrain geometry from GIS can help make all sorts of predictions about vegetative type and potential maximum tree height. Hopefully we can present some of this at the 2005 FOREST SUMMIT (October 13 and 14) this fall. Gary
 RE:  Height density analysis and Historical documentation Robert Leverett Jun 07, 2005 13:24 PDT
 ENTS:      For new members and members with a more casual interest in our tree measuring discussions, I periodically try to put our collective ramblings into perspective. I invite Lee Frelich, Will Blozan, Gary Beluzo, Ed Frank, Tom Diggins, John Knuerr, etc. to join in.      As many of you have no doubt witnessed, ENTS is dedicated to historical documentation of important forest sites. This is not to say that descriptions don't currently exist, but they invariably have gaps. So our documentation does not duplicate what has already been done, but typically proceeds along descriptive lines that have received scant attention in the past. As a consequence of the incompleteness of past documentation efforts by others, sites that would otherwise have been acknowledged as exemplary, or historically significant, and thereby possibly be eligible for special protection status were slipping through the cracks. Good examples of sites that were once threatened include Belt Woods, MD; Zoar Valley, NY; MTSF, MA; a private site in Claremont, NH; and Mackey Mtn., NC. Even well-known sites like Cook Forest State Park fall into the category of having been descriptively bypassed. Before the days of Dale Luthringer, what the resource managers didn't know about the forests of Cook beyond the most superficial descriptions was eye-opening. I am personal witness to this dearth of site-specific knowledge. Fortunately, the situation has turned around for Cook because of Anthony Cook and Dale Luthringer and ENTS's support of Dale. Another example is MTSF, my forest icon. State resource managers saw Mohawk as having a convenient campground. A few saw the aesthetic value of Mohawk, but none had any way of comparing or contrasting the exceptionally tall forests of Mohawk to other Massachusetts sites let alone elsewhere in New England or the Northeast. Consequently, the Commonwealth's tallest trees, icons of a New England past, went largely unnoticed. The story of Zoar Valley in NY is legendary.      ENTS has championed exceptional forest sites that have otherwise gone largely unnoticed. a small contingent of us have spent many hours roaming the sites measuring trees and trying to get a handle on what we are seeing. Concepts like the Rucker index and now height density distributions have evolved to fill the voids. Our measurements and protocols won't tell the whole story, but they are not intended to do that. However, future generations interested in qualitative and quantitative descriptions of say Bullard Woods and how it compares to the forests of the past and present will have far more to drawn upon.      Our latest foray into height density analysis holds promise of providing the detail that serious scientists want to gather on trees populating a site. However, unlike the more typical plot-based data that produces reliable quantitative measures from breast level to the ground and compromises on height data, our heights will be completely reliable. But the height density documentation and analysis that we've begun to explore will be time consuming. However, with John Knuerr, Gary Beluzo, Susan Scott, myself and hopefully John Eichholz perfecting the process, we'll be able to pass on the lessons we learn to save others time. A recap of the process as we now envision it follows.         1. Locate the center of a circular plot with a radius of 28 yards (25.6 meters).         2. The recorder records the start time.         3. The recorder or measurer gets GPS coordinates for the center of the plot.         4. The recorder, positioned at the plot center with a laser rangefinder, clinometer, device to measure horizontal angle, and recording worksheet proceeds to direct the activities of one or more measurers.         5. The recorder sends the measurer to each tree within the plot as determined by the rangefinder of circumference 1.0 feet. The trees are tagged for easy subsequent identification. This process is crucial to keeping accurate tabs on what has and has not been measured. Trust us!        6. The recorder sends the measurer to a tagged tree and requests the following information:                 a. species,                 b. circumference at breast height,                 c. full height or height class,                 d. crown exposed or understory,                 e. age class,                 f. condition,                 g. max crown spread (optional)       7. The recorder records the above information along with the distance to the tree and its azimuth.       8. The recorder requests the tag to be removed.       9. Steps 7 and 8 are recorded for each tree in the plot until all trees have been measured.         10. The recorder records the ending time.      The above process can be enhanced by expanding the concept of step 6c to include added stratifications. If each tree is accurately height measured, we can develop whatever height stratifications we wish. Otherwise we might us the following system:        0 - 49.9 ft        50 - 74.9 ft        75 - 99.9 ft        100 - 124.9 ft        125 - 149.9 ft        150 - 174.9 ft        175 and over    The above documentation/measurement protocol would be employed selectively, at least at first, to provide data on the best places within our best sites. Bob Robert T. Leverett Cofounder, Eastern Native Tree Society
 Re: Historical documentation and height density analysis Edward Frank Jun 07, 2005 16:12 PDT
 RE: Historical documentation and height density analysis Gary A. Beluzo Jun 07, 2005 17:18 PDT
 Bob: I would suggest that since multiple recorders will be present and so many tree measurements are being made that TERRAIN GEOMETRY also be assessed at the same visit. The plot aspect, slope, and slope position could be determined very easily. In addition, the Terrain Shape Index (TSI) and Landform Index (LFI) should also be determined. The reason for doing this is threefold: 1) As the recorder has an assistant move around the plot 360 degrees from center to perimeter it would be very easy to also record the % slope from the plot center to the plot perimeter (for TSI) and plot center to horizon (for LFI) with the clinometer at 45 degree intervals starting with North. 2) The resulting terrain information may then be used to statistically examine the relationships between the various terrain factors (i.e. slope, aspect, slope position, TSI, and LFI) and the tree variables measured such as maximum tree height. This can be done most efficiently with a Geographic Information System (GIS). For example, in many of the primary literature studies I have reviewed, terrain variables collectively influence maximum tree height more than do nutrient levels, A-horizon depth, or total soil depth. 3) As ENTS folks begin to employ GIS-based analysis of their sites, the field-based measurements of terrain variability will prove to be invaluable for model calibration. Gary Gary A. Beluzo Professor of Environmental Science Holyoke Community College 303 Homestead Avenue Holyoke, MA 01040
 RE: Historical documentation and height density analysis dbhg-@comcast.net Jun 08, 2005 03:49 PDT
 Gary:    The TSI and LFI are easy additions to the list, especially with the leveling tripod graduated in degrees. Ed:     The height classes I suggested are admittedly arbitrary and should probably be adjusted for the forest being measured. I'll give some examples in my next e-mail that would use different classes. Bob
 Plot survey methods lwin-@hampshire.edu Jun 08, 2005 04:28 PDT
 I've tried both the Interpoint and the circular plot/polar coordinates methods with students in my classes and the plot center method goes much more smoothly. We use plots the same size as CFI plots, so data are comparable. We've used exactly the method you've described - one person at the center coordinating, rovers out "calling" trees (dbh, condition, crown class), "taggers" out tagging trees, numbering them and noting the species on the tag. We found that shooting the back bearing to the center, using a sighting compass, was easier the using a rotating plane table in the center - almost as accurate. Using a laser or a sonic rangefinder is of course infinitely superior to pulling a tape, especially in a brushy plot. The sonic rangefinder works a little better, with a transponder in the plot center - signal goes through trees, while the laser is of course blocked - the distance through trees is actually underestimated, since the speed of sound is different in wet wood than in air! When possible we also have one student using a laptop computer to record the data directly into an Excel spreadsheet - I can send along a copy of one file as an example - the spreadsheet converts polar to Cartesian coordinates and maps the plot as you go (could also now use a polar plot, not an option back when I firat started doing this kind of survey) , so you can walk around and check things - pretty easy to get confused with a group of students - but once teams get the hang of it they can really move. But 3 or 4 plots in a full day was the most we ever did, and that was estimating height visually, not shooting the tops. If the plot center is marked (PVC pipe, witness trees, locust stake painted red) it's pretty easy to resurvey, given the detailed map. No need to mark trees directly, which has been a problem. GPSing the center is also a very good idea, although I have had little success using GPS to return to a plot without witness trees or some other visual signs. In winter good fix has  been possible - summer harder. Sometimes we set a pin in a clearing or a nearby road, then survey in to the plot the hard way with a level or transit. Additional measures that you may have already thought of: core the tallest dominant tree or two to get data for Site Index or to recover site history; use a steel rod about 1/4" in diameter as a soil depth probe - drive it in in 20 places or so until you hit rocks, then measure that depth - you'll need a vice grips to get the rod out on occasion. We also note ground cover vegetation and saplings - Sounds like a wonderful project - I'm teaching Old Growth Forests again this Fall and Forest Ecology in the Spring - perhaps we should get together and coordinate plot locations and survey methods and data formats! Larry ------------- Lawrence J. Winship Professor of Botany, Hampshire College
 RE: Plot survey methods Robert Leverett Jun 08, 2005 05:13 PDT
 Larry:    Gary Beluzo, John Knuerr, Susan Scott, and I (the current team) would be delighted to "coordinate plot locations and survey methods and data formats". Absolutely! Incidentally, we have many white pines tagged in MTSF, courtesy of Lisa Bozzuto and Susan Benoit, that could be used in plots toward several objectives. Just say the word.    I'm especially interested in establishing the kinds of plots we've been discussing in the high performance areas of:    1. MTSF    2. MSF    3. Ice Glen    4. Mount Tom SR    5. Bullard Woods    6. Mount Greylock SR    7. William Cullen Bryant Homestead    8. Broad Brook (Monica's Woods)    9. Canary Island 10. Mount Everett SR Other high performance forests could be added to include a plot or two in Quabbin. I saw Bruce Spencer over the weekend and I'm sure he'd be happy to authorize us to do it. Bob
 More on plot survey methods Robert Leverett Jun 09, 2005 07:40 PDT
 ENTS:    One point to mention in determining the distance from a center point to a study tree using the laser rangerfinder is that when the base to eye level is obscured by underbrush, the simplist solution is to find the lowest visible point on the trunk, shoot that distance, take its angle, and calculate the eye level distance to the tree using the simple formula:      D = distance to point on tree      A = angle to point on tree      H = horizontal (eye-level) distance to tree      H = Cos(A)D    Even if the tree leans toward or away from the observer, the error is usually minimal for trees in the East.    To the protocol previously listed, we could add the slope angle to the perimeter of the plot at the 4 cardinal compass points. The average of the 4 slope angles or their equivalent slope percentages can be used to compute the Terrain Shape Index (TSI) of the center point of the plot. A similar calculation can be done for the Land Form Index (LFI). Gary, please correct me if I am wrong in my use of these terms. Bob
 Re: More on plot survey methods foresto-@npgcable.com Jun 10, 2005 10:28 PDT
 GaryB- Bob's comments on ways to characterize the immediate landscape has me thinking of an old solution that might be "hopped up" to work out...are you familiar with plane table mapping? In the 'good old days', a plane table (on tripod), an alidade (linear "gun sight"/straight edge/compass), a couple of under grads running abneys (clinometers/laser hypsometer)and rag tapes and you'd end up with a surprisingly good landscape characterization... -DonB
 RE: Ash tree seed collection and Lee's observation Robert Leverett Jun 10, 2005 13:04 PDT
 Don:    Have we taken site and individual tree measuring to the point of diminishing returns? From some perspectives and for some purposes, I imagine we have. Squeezing another decimal point out of our methods would seem to be overkill. But for a certain class of unprotected forest sites, courtesy of our intense, and to some, fanatical focus, we have become uniquely qualified to recognize and quantify their special attributes. Who else does it or has done it? There is no other game in town. Our over-focus, and that is my term, has recently allowed us to help others see what they didn't see before. They acknowledge that unprotected sites like Mohawk truly are exceptional and worthy of special protection. But we have a special situation developing on our hands.     The State is currently engaged in a laudable program of identifying forest reserves on public lands. I should be elated. Initially I was and still am pleased, but from what I've seen so far, the program is endanger of going astray. At the least, environmental organizations must come together to push (or shame) bureaucrats into doing the right thing. It's a long story, Don.     Believe it or not, neither MTSF and MSF are presently included in the proposed system of reserves. They were bypassed ostensibly for political reasons to give the Fish and Wildlife Division its "fair share" of reserves. Why the heck does Fish and Wildlife need a share of the reserves? While the fish and wildlife folks do a pretty good job of managing the resources under their control, they, nonetheless, stay almost singularly focused on raising revenue from deer, bear, turkey, grouse, and timber. To them, resources always need to be managed. In my view, Fish and Wildlife has not shown sufficient understanding of the value of reserves to be trusted as a proponent and reliable overseer.    MTSF and MSF may yet qualify when the smaller reserves are identified, but it is obvious to me that even with all the work that FMTSF and ENTS has done in the past, and presented to the state, a sizable percentage of those involved still don't understand the unique attributes of the forests of the Deerfield River corridor, which includes MTSF and MSF. Fortunately, lack of appreciation is not universal. Some state officials have been receptive to our message and in recent years have become strong advocates for protecting sizable parts of MTSF and MSF by whatever method. Forest reserves fit the plan based on their understanding of the exemplary state of the Mohawk and Monroe forests. Guess what/who has shaped their perceptions?    So back to the question about site variables. We'll be trying to understand forest productivity in the Deerfield for years. Of that I have no doubt. I won't see adequate answers in my lifetime, but hopefully, I will see a wider appreciation for what those forests represent and a commitment by EOEA and DCR to protecting them in reserves.     Bob
 Re: Ash tree seed collection and Lee's observation Don Bertolette Jun 12, 2005 09:41 PDT
 Bob- Just now back from Scandanavia, IT SEEMS TO ME THAT YOU'VE FOUND THE BALANCE ON INDIVIDUAL TREE MEASUREMENT ACCURACY/PRECISION, I WAS TRYING TO PROMPT DISCUSSION OF THE DEPTH AND BREADTH OF MEASUREMENTS OF SITE QUALITIES I AGREE THAT THERE SHOULD BE DIFFERENT LEVELS/PRIORITIES FOR DIFFERENT 'CLASSES' OF SPECIAL FOREST SITES.  FROM A FOREST RESTORATION PERSPECTIVE, THE CURRENT PRODUCTIVITY CAN'T BE INDEPENDENT OF THE 'REFERENCE CONDITIONS' FOR THE DEERFIELD CORRIDOR. KNOWING THE HISTORICAL TREATMENT OF THE AREA IS CRITICAL TO UNDERSTANDING WHAT THE PRODUCTIVITY MAY HAVE BEEN PRESETTLEMENT...KNOWING THE RELATIVE PROPORTIONS OF SPECIES OF THE AREA WOULD BE INVALUABLE, AND PERHAPS AVAILABLE FROM POLLEN ANALYSIS FROM NEARBY BOGS AND COVES THAT OFFER SOIL/POLLEN/MACROFOSSIL ACCRETION. IT'S CRITICAL NOT TO TRY TO FREEZE A SPACE IN TIME, BUT TO KNOW ITS PROCESS AND WHEN WE'RE INHIBITING/IMPACTING/ENHANCING IT IS ESSENTIAL IN THE LONGER VIEW.