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Harvard Forest Data Archive


Tree Ring Data from the Harvard Tract in Pisgah State Forest NH 1675-2015

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  • Lead: Neil Pederson
  • Investigators: Daniel Bishop, Javier Martin Fernandez, Tessa Mandra
  • Contact: Information Manager
  • Start date: 1675
  • End date: 2015
  • Status: completed
  • Location: Pisgah State Forest (NH)
  • Latitude: 42.83
  • Longitude: -72.44
  • Elevation: 334 meter
  • Taxa: Acer rubrum (red maple), Betula lenta (black birch), Betula papyrifera (paper birch), Fagus grandifolia (american beech), Pinus strobus (eastern white pine), Quercus rubra (northern red oak), Tsuga canadensis (eastern hemlock)
  • Release date: 2021
  • Revisions:
  • EML file: knb-lter-hfr.410.2
  • DOI: digital object identifier
  • EDI: data package
  • DataONE: data package
  • Related links:
  • Study type: long-term measurement, historical, paleological
  • Research topic: forest-atmosphere exchange; historical and retrospective studies; large experiments and permanent plot studies
  • LTER core area: primary production, populations, disturbance
  • Keywords: climate change, community composition, defoliation, dendrochronology, disturbance, net primary production, permanent plots, tree rings
  • Abstract:

    Is it possible to reconstruct aboveground carbon/biomass from tree rings? If so, how far back in time can researchers go when using tree-ring data in the reconstruction of past biomass? Answers to these questions will have a significant impact on our understanding of dynamics in the terrestrial carbon sink. Long tree-ring records of biomass can reveal intra-annual to annual to multidecadal variations that cannot be resolved by forest census data that is not conducted at annual time steps. Additionally, while these dynamics might be resolved using remote sensing, most remotely-sensed products are only two decades or less in length. By having long records of carbon biomass, we can then identify not only the dominant drivers of biomass, but how the importance of these drivers might change during different eras as environmental factors change (e.g., climate, air pollution, disturbance).

    To test these and other questions, we collected tree-ring records from two 30m radius plots set within Harvard’s Pisgah Tract in Pisgah State Forest, New Hampshire. We can convert these data to biomass using allometric equations and compare tree-ring inferred aboveground biomass to the census data going back in time. Famously, 80% of this tract was knocked down in September 1938 by a strong hurricane. The forest has sine regrown and the plots we installed can be used to understand forest recovery and carbon dynamics in a heavily disturbance forest. Given that this was a known/decently documented event, these data were used by Trotsiuk et al. (2018) to test various growth release methods as applied to tree-ring data.

    Trotsiuk, V., Pederson, N., Druckenbrod, D. L., Orwig, D. A., Bishop, D. A., Barker Plotkin, A., Fraver, S., Martin-Benito, D. 2018. Testing the efficacy of tree-ring methods for detecting past disturbances. Forest Ecology and Management 425: 59-67.

  • Methods:

    Vegetation and tree-ring data

    Vegetation and tree-ring data associated with this dataset were collected by the “PalEON Protocol”. Three plots were established in the EMS Plot where all trees greater than 10 cm diameter at breast height (DBH) in a 13 m radius were mapped (using distance and azimuth from plot center), measured for DBH, placed into canopy strata (dominant, co-dominant, intermediate, and suppressed, life status (live or dead), structural position if dead (snag, log, or stump hole), and cored. Two to three cores were removed from all trees sampled, live or dead, when possible; some were too rotten to core. Decay classes were determined for all deadwood (1 = recent to 5 = nearly soil) following Bunnell and Houde (Bunnell, F.L. and Houde, I., 2010, Down wood and biodiversity--implications to forest practices, Environmental Reviews, 18, pp.397-421) and surveys were made of saplings (all stems 2.5-4.99 cm DBH from plot center out to 5 m) and poles (all stems 5-9.99 in DBH from plot center out to 9 m). This protocol was repeated for 13-20 m from plot center, but only for trees greater than 20 cm DBH, to increase representation and possibly sample a higher proportion of old trees. Tree-ring measurements were taken from all usable cores and portions of usable cores for each plot. Some cores had too much rot or other issues to be useful. The occurrence of a missing or locally absent ring, where a tree did not fully form a ring on the side of the tree that was cored, is designated with a zero.

    Tree-ring file formats

    Data are provided in both traditional Tucson and csv formats. Tucson files are organized by species where the species code is the first two letters of the genus plus the first two letters of the species. Tuscon files contain total raw ring width (.rwl), earlywood ring width (.ewr), or latewood ring width (.lwr). Tucson data can be read as a space-delimited file in most coding languages. In R, package dplR has built-in function read.rwl that converts .rwl files to a data frame (rows become years; columns become ring-width series). For more information on the Tucson data format, please see: Brewer, P.W., Murphy, D. and Jansma, E., 2011. TRiCYCLE: a universal conversion tool for digital tree-ring data. Tree-Ring Research, 67(2), pp.135-144.

    Notes about the data

    PS1 Trees 109, 113, and 117 (TSCA), PS2 Trees 41, 77, 82, and 95 (TSCA), and PS2 Tree 99 (BELE) were unaccounted for after fieldwork. The causes of the missing data are accounted for in the “comments” column of the field notes file (hf410-02-ps-core.csv).

  • Use:

    This dataset is released to the public under Creative Commons CC0 1.0 (No Rights Reserved). Please keep the dataset creators informed of any plans to use the dataset. Consultation with the original investigators is strongly encouraged. Publications and data products that make use of the dataset should include proper acknowledgement.

  • Citation:

    Pederson N. 2021. Tree Ring Data from the Harvard Tract in Pisgah State Forest NH 1675-2015. Harvard Forest Data Archive: HF410 (v.2). Environmental Data Initiative:

Detailed Metadata

hf410-01: trees

  1. site: site and plot identifier
    • PS1: Pisgah Tract Plot 1 (Plot center at 43.06769 N, -73.28870 W)
    • PS2: Pisgah Tract Plot 2 (Plot center at 43.07200 N, -73.28997 W)
  2. tree: tree number
  3. species: species
    • ACRU: Acer rubrum
    • BELE: Betula lenta
    • BEPA: Betula papyrifera
    • FAGR: Fagus grandifolia
    • PIST: Pinus strobus
    • QURU: Quercus rubra
    • TSCA: Tsuga canadensis
  4. date: date of sampling
  5. canopy: canopy position
    • codominant: codominant
    • dominant: dominant
    • intermediate: intermediate
    • suppressed: suppressed
  6. status: alive, dead or non-standing tree position
    • dead: status is unknown
    • Li: live
    • Lo: log
    • Sh: stump hole
    • Sn: snag
    • St: stump
  7. dbh: diameter at breast height (unit: centimeter / missing value: NA)
  8. distance: distance from plot center (unit: meter / missing value: NA)
  9. azimuth: degrees from due north (unit: degree / missing value: NA)
  10. decay: decay class
    • 1: solid wood, recently fallen, bark and twigs present
    • 2: solid wood, significant weathering, branches present
    • 3: wood not solid, bark may be sloughing but nail still must be pounded into wood
    • 4: wood sloughing and/or friable, nail may be forcibly pushed into wood
    • 5: wood friable, barely holding shape, nail may be easily pushed into wood
  11. Orientation: orientation in degrees of fall of log (unit: degree / missing value: NA)
  12. Length: length of log (unit: meter / missing value: NA)

hf410-02: core data

  1. site: site and plot identfier
    • PS1: Pisgah Tract Plot 1 (Plot center at 43.06769 N, -73.28870 W)
    • PS2: Pisgah Tract Plot 2 (Plot center at 43.07200 N, -73.28997 W)
  2. tree: tree number
  3. core: core cardinal direction
    • E: east
    • N: north
    • S: south
    • W: west
  4. species: species ID of individual series
    • ACRU: Acer rubrum
    • BELE: Betula lenta
    • BEPA: Betula papyrifera
    • FAGR: Fagus grandifolia
    • PIST: Pinus strobus
    • QURU: Quercus rubra
    • TSCA: Tsuga canadensis
  5. inner_year: observed innermost year (not always measured)
  6. outer_year: observed outermost year (not always measured)
  7. meas_inner: year of innermost measured ring
  8. meas_outer: year of innermost measured ring
  9. rings: total number of rings measured (unit: number / missing value: NA)
  10. pith: estimated number of rings from pith or at pith (unit: number / missing value: NA)
  11. gap: location, in dates, when there is an observed gap(s) in mounted cores
  12. missing: list of years with missing rings in series
  13. false: list of years with false rings in series
  14. incomplete: list of years with incomplete/partial rings in series
  15. reaction: list of years with “reaction wood” in series
  16. white_ring: list of years with white rings
  17. canopy: estimated condition of tree during early growth years
    • G: gap
    • N: non-gap
    • U: unknown
  18. comments: core-specific comments

hf410-03: tree ring measurements

  1. site: site
    • PisgahTractPisgahForestTSCA: Pisgah Tract
    • PS: Pisgah Tract
  2. species: species
    • ACRU: Acer rubrum
    • BELE: Betula lenta
    • BEPA: Betula papyrifera
    • FAGR: Fagus grandifolia
    • PIST: Pinus strobus
    • QURU: Quercus rubra
    • TSCA: Tsuga canadensis
  3. core: core number
  4. type: ring measurement type
    • ewr: earlywood ring width
    • lwr: latewood ring width
    • rwl: raw ring width
  5. year: year of ring width
  6. rw: measured ring width (unit: millimeter / missing value: NA)

hf410-04: field notes

  • Compression: none
  • Format: pdf
  • Type: document

hf410-05: PalEON sampling protocol

  • Compression: none
  • Format: pdf
  • Type: document

hf410-06: Tuscon files

  • Compression: zip
  • Format: Tuscon ring data
  • Type: document

hf410-07: R script to convert Tucson files

  • Compression: none
  • Format: R script
  • Type: script