You are here

Home » Data & Archives

Harvard Forest Data Archive

HF443

Synthesis of Hemlock Removal Experiment at Harvard Forest 2003-2019

Related Publications

Data

Overview

  • Lead: Audrey Barker Plotkin
  • Investigators: Aaron Ellison, David Orwig, Meghan MacLean
  • Contact: Information Manager
  • Start date: 2003
  • End date: 2019
  • Status: completed
  • Location: Simes Tract (Harvard Forest)
  • Latitude: +42.47 to +42.48 degrees
  • Longitude: -72.22 to -72.21 degrees
  • Elevation: 200 to 240 meter
  • Datum: WGS84
  • Taxa: Tsuga canadensis (eastern hemlock)
  • Release date: 2024
  • Language: English
  • EML file: knb-lter-hfr.443.2
  • DOI: digital object identifier
  • EDI: data package
  • DataONE: data package
  • Related links:
  • Study type: long-term measurement
  • Research topic: large experiments and permanent plot studies; physiological ecology, population dynamics and species interactions
  • LTER core area: disturbance patterns, human-environment interactions
  • Keywords: hemlock, hemlock woolly adelgid, timber harvest, tree maps, vegetation dynamics
  • Abstract:

    In 2023, we synthesized the data from 6 Harvard Forest Hemlock Removal Experiment datasets (HF054, HF106, HF107, HF125, HF126 and HF161) to discern differences between the girdling and logging treatments from 2004-2019.

    Forest insect outbreaks cause large changes in ecosystem structure, composition, and function. Humans often respond to insect outbreaks by conducting salvage logging, which can amplify the immediate effects, but it is unclear whether logging will result in lasting differences in forest structure and dynamics when compared with forests affected only by insect outbreak. We used 15 years of data from an experimental removal of Tsuga canadensis (L.) Carr. (Eastern hemlock), a foundation tree species within eastern North American forests, and contrasted the rate, magnitude, and persistence of response trajectories between girdling (emulating mortality from insect outbreak) and timber harvest treatments.

  • Methods:

    Harvested wood products

    We used harvest records to estimate the volumes of different types of wood products harvested from the two logged plots (hf443-01-wood-prod-vol.csv). These are aggregated for the two plots, so only treatment-level summaries can be made. The totals for each category are further split into whether the wood was utilized at the Harvard Forest or sold.

    Carbon content of wood products

    We used the Massachusetts variant of the state level Harvested Wood Products (HWP) model, HWP-C vR (based on the national level model, USFS HWP-C v1, (Stockmann et al. 2012) to produce estimates for the fate of harvested wood carbon. This HWP model tracks harvested wood from milled roundwood to final products and discard fates. The HWP-C vR model has been used for California, Oregon, and Washington wood-products carbon inventories (Groom and Tase 2022) and we have been updating this model for southern New England. Approximately 55% of the harvested wood from the HF-HeRE remained at Harvard Forest, which allowed us to know the specific end use products and product half-lives for this proportion of the wood. For the wood sold, we knew the timber product from the sale of the timber and assumed standard mill residue proportion and use (the wood not used for the primary wood product during the milling process) as calculated from the most recent southern New England Timber Products Output reports (2018 TPO; https://www.fia.fs.usda.gov/program-features/tpo/). Based on data availability, Northeastern regional estimates of primary product ratios (Smith et al. 2006) and national level data on end-use ratios (McKeever 2009, McKeever and Howard 2011) were used to estimate end-use ratios and disposal and decomposition rates for the sold wood. Based on these ratios, a small proportion of the sold wood is turned into short-lived products or emitted during the milling process, and the remaining primary products are turned into short- and longer-lived products based on species group, timber product, and most common end-use products for these groups (Groom and Tase 2022). In the 50 years post-harvest, the harvested wood end-use products are emitted, recycled, stored in landfills, or remain stored in long-lived products.

  • Organization: Harvard Forest. 324 North Main Street, Petersham, MA 01366, USA. Phone (978) 724-3302. Fax (978) 724-3595.

  • Project: The Harvard Forest Long-Term Ecological Research (LTER) program examines ecological dynamics in the New England region resulting from natural disturbances, environmental change, and human impacts. (ROR).

  • Funding: National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210.

  • 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.

  • License: Creative Commons Zero v1.0 Universal (CC0-1.0)

  • Citation: Barker Plotkin A. 2024. Synthesis of Hemlock Removal Experiment at Harvard Forest 2003-2019. Harvard Forest Data Archive: HF443 (v.2). Environmental Data Initiative: https://doi.org/10.6073/pasta/dd45022c823a25e8e76b1d68362d5f24.

Detailed Metadata

hf443-01: wood product volumes

  1. product: type of wood product
  2. units: unit of measurement
    • board feet: one board foot is 12 inches by 12 inches by 1 inch, or 30 cm by 30 cm by 2.54 cm. Totals are in International 1/4 inch units
    • cords: one cord is 128 cubic feet (3.6 cubic meters)
    • tons: one ton is 2000 pounds (0.9 metric tons) dry mass
  3. total: total volume of wood product in its respective unit (unit: dimensionless / missing value: NA)
  4. HarvardForest: volume of wood product (in its respective unit) utilized at the Harvard Forest (unit: dimensionless / missing value: NA)
  5. sold: volume of wood product (in its respective unit) that was sold (unit: dimensionless / missing value: NA)

hf443-02: carbon content of wood products

  1. yearsUse: year post-harvest (harvest year was 2005)
  2. Cgm2: total carbon in grams per square meter (one value for the two logged plots) (unit: gramPerMeterSquared / missing value: NA)

hf443-03: sample area

  1. plot: plot number (1-8)
  2. stratum: tree height stage
    • Seedling: tree less than 1.3 m in height
    • Sapling: tree greater than 1.3 m in height but less than 5 cm dbh
    • Tree: tree greater than 5 cm dbh
  3. sample.ha: area sampled by plot and stratum (e.g. 0.001 means that 0.001 hectares were sampled for that plot and stratum) (unit: dimensionless / missing value: NA)

hf443-04: tree composition

  1. plot: plot number (1-8)
  2. trt: treatment
    • hemlock: untreated hemlock reference
    • girdled: all hemlock trees girdled
    • logged: hemlock and other trees harvested for timber
    • hardwood: untreated hardwood reference
  3. block: block
    • ridge: ridge block
    • valley: valley block
  4. year: year of measurement
  5. species: species
    • acpe: Acer pensylvanicum
    • acru: Acer rubrum
    • acsa: Acer saccharum
    • bepa: Betula papyrifera
    • bepo: Betula populifolia
    • betula: Betula alleghaniensis & B. lenta
    • caca: Carpinus caroliniana
    • cade: Castanea dentata
    • cagl: Carya glabra
    • caov: Carya ovata
    • casp: Carya sp.
    • fagr: Fagus grandifolia
    • fram: Fraxinus americana
    • frni: Fraxinus nigra
    • havi: Hamamelis virginiana
    • nysy: Nyssa sylvatica
    • osvi: Ostrya virginiana
    • pist: Pinus strobus
    • prpe: Prunus pensylvanica
    • prse: Prunus serotina
    • qual: Quercus alba
    • quru: Quercus rubra
    • quve: Quercus velutina
    • tsca: Tsuga canadensis
  6. dens_ha: number of trees per hectare (unit: dimensionless / missing value: NA)
  7. stratum: tree height stage
    • Seedling: tree less than 1.3 m in height
    • Sapling: tree greater than 1.3 m in height but less than 5 cm dbh
    • Tree: tree greater than 5 cm dbh

hf443-05: hemlock removal synthesis R scripts

  • Compression: zip
  • Format: R script
  • Type: script