Entering Trees Into Our Database

[edfrank]

Entering Trees Into Our Database
by edfrank » Wed Apr 25, 2012 1:55 pm

NTS, There are more and more people participating in the Native Tree Society and who are out there measuring trees.  For those people measuring trees I strongly encourage you to submit your measurements not only to the BBS, but to post them to our Database as well.  http://www.treesdb.org/   Mitch Galehouse has done an excellent job of creating the database (some of it is still under construction.) Please read our tree measuring guidelines before submitting tree measurement data http://www.nativetreesociety.org/measure/Tree_Measuring_Guidelines-revised1.pdf

I want to offer two items of caution for people submitting their measurements to the database.  The heights must be measured using one of three methods: 1) NTS laser rangefinder/clinometer sine-top/sine-bottom methods outlined in our tree measuring guidelines, 2) climb and tape drop measuring the top of the tree also as outlined in our tree measuring guidelines, or 3) by a pole measurement where the height is directly measured using a pole.  If you have measured the tree in some other fashion, then the data does not meet our standards and should not be posted to our database.  If you ave entered trees whoseheight has been measured by other than the methods listed above, please go back and delete these entries.

The second item of caution is the inclusion of multitrunk trees.  We have discussed this subject many times. http://www.ents-bbs.org/viewtopic.php?f=235&t=3948    http://www.nativetreesociety.org/multi/index_multi.htm  For measurement purposes the girths of trees with more than one trunk must not be intermixed with those for trees with single trunks.  A single trunk tree is one that would have a single pith at ground level.  If the tree would have more than one pith at ground level it is a multitrunk tree.  It doesn't matter if it is genetically the same, or growing from the same root stock, by definition used in our guidelines, if it would have more than one pith at ground level it is a multitrunk tree and must be differentiated from single trunk trees.  Presently there is no place in the database structure to enter data for multitrunk trees.  If you have measured one, and want to enter it into the database, please note that it is a multitrunk tree in the comments field, and we can fix it later when the database is complete.  

Trees have been entered in the database that clearly appear in the photograph to be multitrunk trees, yet there is not indication in the comments that they are anything but single trunk trees.  Yes it is up to the measurer to make the final determination in the case where there is a debate about whether something is single trunk or multitrunk, but in some of these cases there is no doubt the trees are multitrunk trees.    (Yes a Nikon Forestry 550 combines both the rangefinder and clinometer and is acceptable). If you have entered a tree that is multitrunked, but failed to indicate that it is multitrunked in the comments section, please go back and edit the submission to reflect this fact.  As an organization we need to maintain and protect the integrity of our data set.

Edward Frank

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[edfrank]

Suggestions For Database Features

On the home page of the Trees Database http://alpha.treesdb.org/Main, Mitch has set up a link to a survey where people can suggest or vote on features and changes for an upcoming release.  I would urge people to participate in the development and evolution of the database by participating in the survey.

Ed Frank

[dbhguru]

NTS,

  I'll add a few comments to what Ed has said. The TruPulse and Impulse lasers from LTI have the sine method implemented in their circuitry, but the method is not the HT routine commonly advertised and used for tree heights. With the TruPulse line, the Vertical Distance (VD) return implements the sine method.

  The new Nikon Forestry 550s include the 3-point height routine (trunk distance shot-crown angle-base angle), which is an implementation of the risky tangent method. It is the two point routine that does the job we need.

   Except for the people who thoroughly understand the behind the scenes mathematical models, use of the tangent method is a prescription for introducing errors of varying magnitude, some extraordinarily large. The people who pressured Nikon to add the 3-point method are either damn slow learners, just lazy, only measure young plantation conifers, or are really unconcerned with accuracy. Sorry, for being so blunt.

   We have had many, many discussions in NTS on the right methods to use in measuring the common tree dimensions of girth, height, and spread. We  have Will Blozan's tree measuring guidelines, Ed Frank's beginner's guidelines, and countless posts from yours truly. Newcomers may find themselves overwhelmed with all this material. To them, I say please don't hesitate to ask questions. We will always respect from where you are coming from and be anxious to help. It would be unfair of us to expect you to wade through all the material in the BBS, especially when you are new and may have previously received advice from others about how to properly measure trees.

Bob

[KoutaR]

The people who pressured Nikon to add the 3-point method are either damn slow learners, just lazy, only measure young plantation conifers, or are really unconcerned with accuracy.

Probably they made it for forestry people who don't need high accuracy but don't want to spend time with searching for canopy openings clear from clutter.

Anyway that makes things more complicated. Almost all the European laser measurers we know (yes, their number increases) use Nikon 550. We have thought we can accept a measurement if it has been made with Nikon 550, for example. But now we should also ask which method was used... I think all the measurers don't understand the methods, they only measure...

Kouta

[dbhguru]

Kouta,

  Yes, the use of the Forestry 550 is no longer a guarantee of a sine-based measurement.

Bob

[bountreehunter]

i have deleted my entries and apologize.

[fooman]

Kouta,

  Yes, the use of the Forestry 550 is no longer a guarantee of a sine-based measurement.

Bob

Do you mean the new Nikon Forestry Pro (http://www.nikon.com/products/sportoptics/lineup/laser/forestrypro/index.htm), rather than the old Forestry 550  (http://www.nikon.com/products/sportopti ... aser/f550/)  or the identical (with the old Forestry 550 ) 550AS (http://www.nikon.com/products/sportopti ... /index.htm).  The Forestry Pro is not the Forestry 550 ...

To summarise:

Forestry 550  = Good mode (sine method for height and two point measurements)
550 AS = Good mode (sine method for height and two point measurements)
Forestry Pro = Good mode (sine method for height and two point measurements) and Bad mode (3 point method)

When I do height measurements with my Forestry 550, I use the height mode to scan along the tops to find the highest.  As this does not involve a baseline, it must use the sine method (angle, plus length of hypotenuse).  I then use the 2-point mode to measure from base (if visible) or a nearby reference (if base not visible) to the highest top.  Followed by a measurement between the base and the reference, if that is required to get a total height. Given that the two point measurement is difference between two normal (sine-method) heights in the Forestry 550, that is a pretty robust method, as far as I know.

Cheers,
Matt

[dbhguru]

Matt,

  You are right on the money.

Bob