Hi Lindsey et al.,
Sorry for the late reply – I have been away for the last two weeks.
Looking at the plot inventory data, I am a bit concerned that there are so few trees per species for many of the plots. For dendrochronology analysis most researchers use 10 or more trees per species to get
reliable averages that avoid tree-to-tree variations in growth due to the many other random factors (like micro-site or place-based competition) that effect growth. In studies that involve treatments (like NuPert or with this study) the number of trees per
species per plot can be reduced (assuming a cohesive and strong treatment effect). However, here even for the two most common tree species (sugar and red maple) there are only 3 plots with good sample sizes and one plot (#10) with no trees form these species.
It could be that data from just 2-3 trees will provide means and standard errors sufficient to detect differences (especially if treatment effects are large), but this could be a gamble.
On a related note – how bogus would it be to restrict the random allocation of treatments among plots to assure that the plots with many trees per species (like plots 2, 3 and 7 for red maple and 5, 6 and 9 for
sugar maple) are distributed to different treatments (possibly control, medium and high ice loading) so that we can better discern the interplay of sample size and treatment impacts?
Thoughts?
-Paul-
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From: hubbardbrookise-bounces@lists.sr.unh.edu [mailto:hubbardbrookise-bounces@lists.sr.unh.edu]
On Behalf Of Rustad, Lindsey -FS
Sent: Monday, May 25, 2015 5:55 AM
To: hubbardbrookise@lists.sr.unh.edu; Staples, Joe; gwj4@wildcats.unh.edu; Wendy Leuenberger (wleuenbe@syr.edu); Francis Bowles (fpmc.bowles@gmail.com)
Subject: [HubbardBrookISE] ISE Update - Feedback on Plot Location Consent Needed!
Dear ISER’s,
Lots happening in the field! A summary is below:
1.
We have located ten plots that meet most of our plot criteria.. Attached are two maps (plots on LIDAR; plots on Google Earth) showing how the plots fit in this area. The plots are 20 x 30-m, (with an inner 10 x 20-m study plot, subdivided
into 8 5 x 5-m plots), with a minimum of 10 m between plots. Access to the plots from the road, and access to the Hubbard Brook from the plots are good. Them maps and additional photographs of the plots are also included in the ISE Site Search pdf that
is attached.
2.
A closer survey of the vegetation turned up more sugar maple than originally noted. Attached is a spreadsheet showing the dominant and co-dominant trees on the plots and in the inner study plot. For the inner plots, we have 1-8 sugar
maple on each plot, 1-7 red maple on all plots but one, and 1-5 yellow birch on 8 of the 10 inner plots. For the two with no yellow birch on the inner plots, there is yellow birch in the buffer zones. All plots have a consistent understory of American beech
and hobblebush.
3.
Scott Bailey came out with us on May 20. Soils are mostly some variant of Spodosol, with the anticipated variation between pits and mounds and presences of current and buried tip ups. The O is remarkably deep (10-20 cm), sometimes
with A transition in to B, and sometimes with abrupt but intermittent E’s. One plot, 8, closest to the valley bottom, has much finer textured silt soils. It is somewhat of an outlier, but we do not
have more space in that area to move the plots. Scott will provide more official notes next week.
4.
Attached is also a map of ISE Instrumentation to show how our various destructive and non-destructive sampling fits into an idealized sub-plot. We have laid thisout on the floor at the Peirce lab and
it is busy but doable.
5.
Kudos to Geoff Schwaner, Amey Bailey, Scott Bailey, John Campbell, Matt Vadeboncoeur, Ian Halm, Don Mower Frank Bowles, and Wendy Leuenberger for many hours and days locating and relocating plot corners and identifying trees and soils!
6.
LET US KNOW IF YOU NEED MORE INFORMATION ON THE PLOTS OR HAVE CONCERNS ABOUT THIS LOCATION. MY PERSONAL 2 CENTS IS WE HAVE AN IDEAL SPOT FOR THIS EXPERIMENT. DISCUSSIONS WITH
OTHERS WITH EXTENSIVE KNOWLEDGE OF THE HUBBARD BROOK LANDSCAPE HAVE FAILED TO COME UP WITH SUGGESTIONS OF OTHER PLACES FOR US TO CHECK OUT. BUT WE WANT TO HEAR FROM YOU TO KNOW IF YOU HAVE WORRIES ASAP or by end of day on Wednesday, May 27th.
We are marking corners now, but will not install anything until June 3 or 4th.
7.
We have hired a crew of 5 for the summer, with additional help from ‘floaters’, Charlie’s post doc, and several interns and volunteers from the University of Southern Maine. Geoff Schwaner is the field crew leader, and you can direct
questions to him as needed at: gwj4@wildcats.unh.edu. Geoff will be with us throughout the year, and will also oversee fall and winter sampling and activities. Geoff has worked for us in past summers, and spent
the last year, basking in the sun at the Luquillo Experimental Forest in Puerto Rico working for Bill McDowell, The suggested calender of activities is attached.
8.
The ‘Away Team’ of Sarah and Stacie started last week, under John Campbell’s able guidance. They are busy figuring out protocols, finding sites on maps, ordering supplies, and did one site visit last week with the FS scientist who set
the plots up 17 years ago.
9.
Charlie and I (and a cast of individuals from FS and Syracuse Sponsored programs) are working on finalizing budgets and setting up subawards and agreements.
10.
All documents listed here are in the ISE Dropbox. If you do not have access to this Dropbox let me know ,and I will add you.
11.
I filled out my registration for the HB meetings and put in an abstract for a 10 minute slot for the iSE. We can coordinate the talk as we get closer. We would also like to hold an ISE meeting on the plots during that week, and will
suggest times shortly. I will also send out a doodle poll for times for a team conference call in June.
Feel free to reply to this with an update of your own activities!
Best,
Lindsey and John
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