Hemlock History Plots

Data

• hf053-01: tree data

Overview

• Lead: David Foster, Jason McLachlan
• Investigators: Audrey Barker Plotkin
• Contact: Audrey Barker Plotkin
• Start date: 1995-01-01
• End date: ongoing
• Location: Prospect Hill Tract, Slab City Tract (Harvard Forest)
• Latitude: +42.45 to +42.55
• Longitude: -72.22 to -72.18
• Elevation: 250 to 350 meters
• Taxa: Tsuga canadensis (eastern hemlock)
• Research topic: invasive, plot
• Study type: long-term measurement
• LTER core area: disturbance
• Keywords: forest dynamics, hemlock, land use, tree maps
• Release date: 2006
• EML version: knb-lter-hfr.53.8
• Revisions:
• Related links:
• Hemlock Understory Vegetation Plots
• Overstory Mapped Tree Plots
• Abstract:

  Hemlock (Tsuga canadensis) forests in New England are changing rapidly with the invasion of the hemlock woolly adelgid (HWA, Adelges tsugae), an exotic insect pest that kills hemlock trees. The adelgid is just beginning to be observed at Harvard Forest, making this the right moment to begin intensive physiological, ecological and monitoring studies of our hemlock forests. We gathered detailed baseline information for several hemlock stands across Harvard Forest. We surveyed community vegetation structure and composition, and began to monitor soil nitrogen cycling. These measurements will allow us to link the long-term history of these hemlock stands to other current studies of hemlock response to adelgid infestation, and will provide the basis for intensive study of hemlock dynamics with the stands' anticipated decline.

• Methods:

  Four, 30m x 30m plots were established in 1995. Species, crown class, size (diameter at breast height) were determined. Trees were mapped using INTERPT software (HF023). Trees were remeasured in 2002 and hemlock trees rated for vigor.

• Use:

  This dataset is released to the public and may be freely downloaded. Please keep the designated Contact person informed of any plans to use the dataset. Consultation or collaboration with the original investigators is strongly encouraged. Publications and data products that make use of the dataset must include proper acknowledgement. For more information on LTER Network data access and use policies, please see: http://www.lternet.edu/data/netpolicy.html.

• Citation:

  Foster D, McLachlan J. 2006. Hemlock History Plots. Harvard Forest Data Archive: HF053.

Detailed Metadata

hf053-01: tree data

1. Plot: one of four plots
   • PH2: 30m x 30m hemlock history plot located on Prospect Hill, Compartment 2
   • PH7: 30m x 30m hemlock history plot located on Prospect Hill, Compartment 7
   • SC9: 30m x 30m hemlock history plot located on Slab City, Compartment 9
   • SC10: 30m x 30m hemlock history plot located on Slab City, Compartment 10
2. Tree: all trees are tagged in the field with their number. Number system not continuous.
3. Species: first two letters of genus and species name of tree
   • ACRU: Acer rubrum
   • BEAL: Betula alleghaniensis
   • BELE: Betula lenta
   • BEPA: Betual papyrifera
   • FAGR: Fagus grandifolia
   • FRAM: Fraxinus Americana
   • FRPE: Fraxinus pensylvanica
   • PIST: Pinus strobes
   • PRSE: Prunus serotina
   • QURU: Quercus rubra
   • TSCA: Tsuga canadensis
   • UNK: Unknown
4. CC95: crown class rating, noted in 1995
   • D: dominant and codominant
   • C: intermediate
   • I: suppressed
   • S: second layer (umbrella shaped hemlocks)
5. dbh95: diameter at breast height (1.37m) in 1995 (centimeter )
6. dbh02: diameter at breast height (1.37m) in summer 2002 (centimeter )
7. vigor02: vigor
   • 1: 0-25% foliage loss
   • 2: 25-50% loss
   • 3: 50-75% loss
   • 4: 75-99% loss
   • 5: dead
8. X: corresponds with the X axis of the plot, which ranges from 0-30 m (meter )
9. Y: corresponds with the Y axis of the plot, which ranges from 0-30 m (meter )
10. Notes: notes about whether a tree is dead, fallen, or unusual