Coppice Shoots

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

Moderators: edfrank, dbhguru

Post Reply
User avatar
dbhguru
Posts: 4464
Joined: Mon Mar 08, 2010 9:34 pm

Coppice Shoots

Post by dbhguru » Sun Aug 09, 2015 11:42 am

Matt,

Outstanding! You caught the shoot at its infancy in your photo. Capturing what is happening around the root collar in photographs is a necessary step in the analysis. An important step in setting the future course is to decide how we want to treat coppice shoots in big tree competitions. If we decide that a stem began as a coppice shoot off of a main trunk and it fuses to the main trunk, do we treat it as part of the main trunk or discount it, either partially or wholly. If we decide to discount it partially, by what method? Should the species enter the picture? Do we establish more rules for pith tracings? These are questions that need to be answered or we will continue to see tree forms make it into the National Register that we really don't think should be there, but can exclude on the basisi of the existing rules.

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
Matt Markworth
Posts: 1302
Joined: Fri Nov 23, 2012 8:41 pm

Re: Coppice Shoots

Post by Matt Markworth » Sun Aug 09, 2015 3:18 pm

Bob,

Thanks. I'll keep an eye out for more examples.

For the silver maple example, the tree is putting it's energy into the shoot, so it seems that the tree should be given "credit" for the shoot for the purposes of comparing it to other trees. If we were comparing volume, then I'd say give the tree full credit for the shoot.

I don't consider the shoot to be part of the trunk, so I don't feel completely comfortable including it into the trunk circumference for the purposes of a champion tree list. Maybe the tree could be given some "extra credit" for the shoot, over and above what the main trunk earns for circumference, height, and spread. This would preserve the scientific nature (what one stem of the species can produce) of the main trunk measurement and the associated spread, but still give the tree some extra points for the extra shoot it's been putting energy into.

I'm not quite sure how the extra points would be determined. Maybe if a shoot had 10% of the volume of the main trunk, then the whole tree would be given a 10% bonus on the number of points. But, then we'd be back to calculating volume and that's not currently feasible in the context of a champion tree list. I'd be interested if others have ideas on how to determine this type of "extra credit." I think the idea that Zane started and that you modified for the purposes of circumference might be the direction to go, and maybe separate out those extra points as a 4th measurement (circumference, height, spread, subordinate trunk credit), so that the first 3 traditional measurements remain intact and remain comparable to single stems.

Matt

User avatar
Erik Danielsen
Posts: 854
Joined: Mon Mar 17, 2014 5:46 pm

Re: Coppice Shoots

Post by Erik Danielsen » Sun Aug 09, 2015 4:46 pm

Bob, I've been mulling over the concept since you explained it yesterday. The recommendation above in which, given an agreed upon formula for discounting a portion of the coppice stem, the points added by the discounted stem are noted separately makes a great deal of sense in seeking to mollify disagreements between those who do and do not want to apply any "credit" for coppice stems. At the least this should be reasonably practical to apply to champion tree contenders with just one or two coppice stems and an obvious main stem.

The red oak I mentioned with 5+ stems and an 18'+ cbh might provide a good thought-problem in discussing how far the concept can be practically pushed. In particular it seems that the tree is a stump coppice, in which case there is no longer a "main stem" to consider at all. All the stems seem to be of roughly the same age. A pith test would probably find them not convergent, though it's certainly possible that they all originated above ground level when emerging from the probable origin stump. Origination from multiple seeds seems unlikely as nearly the entire stand is singlestem. I'll drop by and take some photos this afternoon.

Post Reply

Return to “Measurement and Dendromorphometry”