Tree Measurement Notation and the public

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

Moderators: edfrank, dbhguru

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

Tree Measurement Notation and the public

Post by Erik Danielsen » Mon Jan 25, 2016 12:49 pm

In my recent work measuring trees with David Burg of WildMetro in NYC, a concern has come up that I think would be worth a conversation and perhaps establishing some standard practices. Part of WildMetro's mission is communicating to the public about natural resources in NYC, so of course David wanted to convey my measurements of the large white oaks we measured along with the photos he took. I presented them as I normally would here with everything written as feet and tenths-of-a-foot, for example 15.9'cbh, 87.6' high, 123.2'ACS, etc. David responded that he found this notation confusing and asked for clarification, and further noted that members of the general public could be expected to find this confusing as well. 15.9'cbh might be interpreted as 15' 9", for example.

Driving this point home, a simultaneous conversation in the comments on one of Matt Markworth's facebook photos involved David posing that same issue, and was promptly told by an NTS facebook member that such notation was, in fact, "slang" for feet and inches, rather than feet and tenths-of-a-foot (which I'm sure we all understand is the actual case). Clearly, even within our own community there is some presence of confusion on this point.

I'll post a screenshot here of the conversation as Matt and Eli stepped in with corrections. I stand in agreement with the fact that the existing notation is the most practical we have for use within the BBS (site reports, etc.), for scientific papers, etc. We're all used to thinking in terms of feet, and we can all mentally divide a foot into tenths. In addition, we all understand the limits of accuracy in our measurement techniques, and that "87.9' high" means the tree is almost definitely between 87 and 88 feet tall, leaning strongly toward 88, with significant potential variances up up to a foot or two. Certainly we understand that we don't mean that the tree is certifiably 87 feet and 9/10 tall to the dot, much less 87 feet and 9 inches tall (with exception to, for example, Bob putting Zeus on the tripod and giving us numbers to the centimeter).

For presenting information to the public, though (which will probably be increasingly important in filling out the potential of NTS's mission) it becomes necessary to shave off a bit of that nuance. My suggestion is that for circumference, it's most appropriate to notate in inches or feet+inches. The public understands that and it avoids any confusion with the use of decimal points. For height and spread, however, I'd propose that we should round to whole feet. Most state champion listings already do so. Some of us may already be in this or similar practice, but I think that we should collect our thoughts, examine any possible objections and alternatives, and from that it may be appropriate for the AF guidelines working group to add a section clarifying the subject to the official AF measurement guidelines document.
Attachments
The facebook conversation in question
The facebook conversation in question

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

Re: Tree Measurement Notation and the public

Post by Don » Mon Jan 25, 2016 3:53 pm

Eric-
A well though-out post on a topic not often addressed.
Ultimately, the devices we measure with come in units of feet, and decimal feet. This comes not from AF or NTS originally, but traditional units of measurement for foresters and surveyors for hundreds of years . Decimal units provide a more simple means of dividing and multiplying than feet and inches.
And David and Tom's confusion is just that...feet and decimal feet is American Standard, not metric measure.
My suggestion is that rather than change traditional, accepted and convenient measurement units to reduce their confusion, that we use this as an opportunity to educate them. Worst case scenario, they continue to utilize the feet and inches units for WildMetro, which is their prerogative, and appropriate to their audience. But not ours. Their's is a provincial usage, ours is national.
If they venture very far into the big tree world, they will benefit. Americans have resisted going metric for decades now, and are being drug into it against their will. But it is inevitable. Already, researchers of all fields across the globe have accepted the metric system of measurement. It's only a matter of time.
-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
Will Blozan
Posts: 1153
Joined: Fri Mar 12, 2010 7:13 pm

Re: Tree Measurement Notation and the public

Post by Will Blozan » Mon Jan 25, 2016 6:38 pm

Erik,

Good topic that has been touched on before.

Firstly, Mr. Burg needs to back off a bit as his arguments are weak. Just because English units are not base ten, this does not mean a 1/10th of a foot is any less valid than a tench of a meter. After all, units are arbitrary to begin with, and only defined in modern times by wavelengths after the fact, not before.

As for confusion, that too, is weak. If you cannot recognize a decimal point then you likely will not recognize the significance of the stated measurement. Just because this stupid country holds out to using the English system doesn't mean we have to cater to those with little grip of math. Those having little grip would certainly benefit from the Metric system!

Also, the statement of the decimal foot being a "slang" term for feet and inches is not correct and offensive to myself and probably others in NTS. My work to perfect height measurements via lasers/SINE/tapedrops has validated the use of 1/10th of foot as opposed to the nearest .5 foot (oh sorry, 6" for those so challenged) foot, or rounding up or down. Seriously, a whole foot is just as precise and determinate as a foot with a decimal after it. Choosing on or the other makes no impact on the stated dimension within the confines of our range of known error.

Finally, I am not going to convert my laser readouts in 1/10 foot or 1/10 yard to inches. No way.

Will

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

Re: Tree Measurement Notation and the public

Post by dbhguru » Mon Jan 25, 2016 6:56 pm

Erik,

Ditto to what Don said. A number such as 15.9 should always be interpreted as 15 and 9/10s. Any other interpretation would go against traditional arithmetic notation.

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

Re: Tree Measurement Notation and the public

Post by Erik Danielsen » Mon Jan 25, 2016 10:56 pm

I hope my intent here is not being misinterpreted- certainly no one here would be prone to such a confusion. Decimal feet (and metric, inevitably) is useful and accepted for what we do here; I'm not about to stop using it myself. I'm also not at all willing to devalue anyone's hard work in achieving high degrees of accuracy in precision measurement. Certainly I'm not endorsing the "slang" comment.

I think that the work of NTS can be usefully applied to educating a diverse lay audience about our trees and forests. Those audiences may be less numerically literate than we'd like, but if some of us do choose to engage that audience, I think it's worth pondering how information should be packaged to be most meaningful and accessible to the greatest number, which for me so far includes children as well as adults who have little formal education but are interested in doing good for their communities (the staten island zoo and Citizen Pruners are currently expressing interest in educational talks and demonstrations, and I'm also doing some work for WildMetro). If you're not working with those audiences and have no desire to, it's really not relevant. For those of us who do, though, I think it'd be sensible to agree on standard practices for formatting information. Public educational programming about trees and forests is just as full of bad numbers as state big tree listings and forestry books. As those who take a stronger interest get deeper into it, obviously they should adopt the same standard practices we use here, as those are more suited to the actual work. The NTS audience and WildMetro's audience are not mutually exclusive, and the latter (and efforts like it) can certainly feed into the former, the more people are exposed to an interest in finding and measuring trees.

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

Re: Tree Measurement Notation and the public

Post by dbhguru » Tue Jan 26, 2016 8:09 am

Erik,

Yes, I realized that you weren't embracing their position, but explaining the situation. We're behind you 100%. I would be doing the same as you are doing, working with a local tree organization to promote tree appreciation.

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
Will Blozan
Posts: 1153
Joined: Fri Mar 12, 2010 7:13 pm

Re: Tree Measurement Notation and the public

Post by Will Blozan » Tue Jan 26, 2016 8:26 am

Erik,

Just for the record, my comments were not directed to you, but a reaction to Burg and Robison.

I have done many talks to interested lay people and believe me, a few decimal points is the least of the issue with regard to getting a point across. Many folks use "150 feet tall'" and "6 feet in diameter" flippantly- with no real idea of what those numbers mean. Very, very few can tell the difference between an 80' tree and a 120' tree. To us so involved in teasing out the superlatives- a single foot more for a species is exciting. To most, a dozen feet will illicit no response.

Keep it simple and in terms that can be comprehended or imagined. Height relative to buildings, stories, monuments. Diameter (not girth) in feet, cab-width, walking pole length, etc. Volume in apartment sizes, gallons of milk... Visual and mental aids help. They'll understand decimals if they get past the visual aids part.

Will

User avatar
DougBidlack
Posts: 425
Joined: Sun Mar 14, 2010 4:14 pm

Re: Tree Measurement Notation and the public

Post by DougBidlack » Tue Jan 26, 2016 7:09 pm

Erik, Don, Bob, Will,

not to hijack this thread but might this be a good time for a discussion on the merits of switching to the metric system. I hate our current system for so many reasons!

BTW, I have nothing to add to Erik's original post because I think Don and Will must have grabbed the thoughts right out of my own head.

Doug

User avatar
Will Blozan
Posts: 1153
Joined: Fri Mar 12, 2010 7:13 pm

Re: Tree Measurement Notation and the public

Post by Will Blozan » Thu Jan 28, 2016 10:36 am

DougBidlack wrote:Erik, Don, Bob, Will,

not to hijack this thread but might this be a good time for a discussion on the merits of switching to the metric system. I hate our current system for so many reasons!

BTW, I have nothing to add to Erik's original post because I think Don and Will must have grabbed the thoughts right out of my own head.

Doug
Moving to the TDI system would make units irrelevant... ;)

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

Re: Tree Measurement Notation and the public

Post by Don » Thu Jan 28, 2016 4:20 pm

Will
Maybe you could remind us of the Ins and Outs, the Pros and Cons of the TDI system?
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”