Hemlock Understory Vegetation Plots



	Hemlock Understory Vegetation Plots HF048 EML Publications Archive Data hf048-01: o-layer hf048-02: substrate hf048-03: herb hf048-04: shrub hf048-05: seedling hf048-06: sapling hf048-07: species distribution Overview Lead: David Foster, David Orwig Investigators: Audrey Barker Plotkin Contact: Audrey Barker Plotkin Start date: 2002-01-01 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: plot, community Study type: long-term measurement LTER core area: disturbance Keywords: hemlock woolly adelgid, Tsuga canadensis, understory vegetation Release date: 1999 EML version: knb-lter-hfr.48.8 Revisions: data updated 2009-05-20 Related links: Ecosystem Response to Hemlock Woolly Adelgid in Southern New England Hemlock History 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. Nearly all saplings were hemlock; sapling densities ranged from 183-1645 stems/ha. Understory flora characteristics were sampled in 10- 1m2 subplots within each overstory plot. Across all sites, herb and shrub cover was very low, reflecting the dense shade and deep organic layer present in these hemlock stands. Species richness ranged from 6-15 understory species found in each 20x20 or 30x30m plot. Methods: In 2002, we set up two transects running north-south through each of the following plots for understory vegetation sampling. Five 1 m2 subplots were spaced evenly along each transect. We labeled the NW corner, unless otherwise marked. Transects are marked with string and yellow tent stakes (no string at Jenkins plots), and plots are marked with pink flags. We estimated percent cover for herbs, shrubs, and seedlings to the nearest one percent. We counted the number of seedlings by species. A seedling is a tree less than 1.3m tall. If rocks or coarse woody debris covered a significant portion of the plot, their percent cover was recorded. In addition, the depth of the organic soil layer was measured to the nearest 0.5 cm at the NW corner of each subplot. We searched each plot and compiled a species list for the entire 20m x 20m or 30m x 30m area. Saplings were tallied by species across the plot. A sapling is a tree greater than 1.3m tall but less than 8cm in diameter. They were noted live or dead. 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, Orwig D. 1999. Hemlock Understory Vegetation Plots. Harvard Forest Data Archive: HF048. Detailed Metadata hf048-01: o-layer Plot: plot code HG1: 20m x 20m plot within hemlock woodlot mapped plot on Prospect Hill Tract, Compartment 2 (the one with the huge O layer closest to BG swamp) HG2: 20m x 20m plot within hemlock woodlot mapped plot (has lots of hemlock seedlings) HG3: 20m x 20m plot just outside hemlock woodlot PH2: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 2 PH7: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 7 SC1: 20m x 20m plot hemlock plot on Slab City Tract, Compartment 9 SC2: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC3: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC9: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 9 SC10: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 10 Subplot: number of 1m2 subplot Depth02: depth of organic soil layer to the nearest 0.5 cm in 2002 (centimeter ) hf048-02: substrate Plot: plot code HG1: 20m x 20m plot within hemlock woodlot mapped plot on Prospect Hill Tract, Compartment 2 (the one with the huge O layer closest to BG swamp) HG2: 20m x 20m plot within hemlock woodlot mapped plot (has lots of hemlock seedlings) HG3: 20m x 20m plot just outside hemlock woodlot PH2: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 2 PH7: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 7 SC1: 20m x 20m plot hemlock plot on Slab City Tract, Compartment 9 SC2: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC3: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC9: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 9 SC10: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 10 Subplot: number of 1m2 subplot Type: substrate type rock: rock tree stem: tree stem woody debris: woody debris Cover02: percent cover of each substrate type in 2002 (dimensionless ) hf048-03: herb Plot: plot code HG1: 20m x 20m plot within hemlock woodlot mapped plot on Prospect Hill Tract, Compartment 2 (the one with the huge O layer closest to BG swamp) HG2: 20m x 20m plot within hemlock woodlot mapped plot (has lots of hemlock seedlings) HG3: 20m x 20m plot just outside hemlock woodlot PH2: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 2 PH7: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 7 SC1: 20m x 20m plot hemlock plot on Slab City Tract, Compartment 9 SC2: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC3: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC9: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 9 SC10: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 10 Subplot: number of 1m2 subplot Species: species code GAPR: Gaultheria procumbens MIRE: Mitchella repens NEMO: Nemopanthus mucronata RHRO: Rhododendron roseum VAAN: Vaccinium angustifolium VIAL: Viburnum alnifolium\ Cover02: percent cover of herbs to the nearest 1% in 2002 (dimensionless ) hf048-04: shrub Plot: plot code HG1: 20m x 20m plot within hemlock woodlot mapped plot on Prospect Hill Tract, Compartment 2 (the one with the huge O layer closest to BG swamp) HG2: 20m x 20m plot within hemlock woodlot mapped plot (has lots of hemlock seedlings) PH2: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 2 PH7: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 7 SC1: 20m x 20m plot hemlock plot on Slab City Tract, Compartment 9 SC2: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC3: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC9: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 9 SC10: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 10 Subplot: number of 1m2 subplot Species: species code GAPR: Gaultheria procumbens MIRE: Mitchella repens NEMO: Nemopanthus mucronata RHRO: Rhododendron roseum VAAN: Vaccinium angustifolium VIAL: Viburnum alnifolium\ Cover02: percent cover of each species within the 1m2 subplot to the nearest 1% in 2002. For species present but with cover less than 1%, cover is assigned to be 0.5% (dimensionless ) hf048-05: seedling Plot: plot code HG1: 20m x 20m plot within hemlock woodlot mapped plot on Prospect Hill Tract, Compartment 2 (the one with the huge O layer closest to BG swamp) HG2: 20m x 20m plot within hemlock woodlot mapped plot (has lots of hemlock seedlings) HG3: 20m x 20m plot just outside hemlock woodlot PH2: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 2 PH7: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 7 SC1: 20m x 20m plot hemlock plot on Slab City Tract, Compartment 9 SC2: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC3: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC9: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 9 SC10: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 10 Subplot: number of 1m2 subplot Species: species code ACRU: Acer rubrum BESP: Betula spp. PIRU: Picea rubens PIST: Pinus strobus PRSE: Prunus serotina QURU: Quercus rubra TSCA: Tsuga canadensis UNK: Unknown Density02: number of each species of seedling within the 1m2 subplot in 2002 (numberPerMeterSquared ) Cover02: percent cover of each species within the 1m2 subplot to the nearest 1% in 2002. For species present but with cover less than 1%, cover is assigned to be 0.5% (dimensionless ) hf048-06: sapling Plot: plot code HG1: 20m x 20m plot within hemlock woodlot mapped plot on Prospect Hill Tract, Compartment 2 (the one with the huge O layer closest to BG swamp) HG2: 20m x 20m plot within hemlock woodlot mapped plot (has lots of hemlock seedlings) HG3: 20m x 20m plot just outside hemlock woodlot PH2: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 2 PH7: 30m x 30m hemlock history plot located on Prospect Hill Tract, Compartment 7 SC1: 20m x 20m plot hemlock plot on Slab City Tract, Compartment 9 SC2: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC3: 20m x 20m plot Jenkins plot on Slab City Tract, Compartment 9 SC9: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 9 SC10: 30m x 30m hemlock history plot located on Slab City Tract, Compartment 10 TSCA live: numbers of live Tsuga canadensis individuals (number ) TSCA dead: numbers of dead Tsuga canadensis individuals (number ) ACRU live: numbers of live Acer rubrum individuals (number ) ACRU dead: numbers of dead Acer rubrum individuals (number ) FAGR live: numbers of live Fagus grandifolia individuals (number ) FAGR dead: numbers of dead Fagus grandifolia individuals (number ) hf048-07: species distribution Type: vegetation type F: ferns / lycopods H: herbs / shrubs T: trees Species: species name (scientific and common) HG1: presence or absence of each species in the plot 0: absent 1: present HG2: presence or absence of each species in the plot 0: absent 1: present HG3: presence or absence of each species in the plot 0: absent 1: present PH2: presence or absence of each species in the plot 0: absent 1: present PH7: presence or absence of each species in the plot 0: absent 1: present SC9: presence or absence of each species in the plot 0: absent 1: present SC10: presence or absence of each species in the plot 0: absent 1: present SC1: presence or absence of each species in the plot 0: absent 1: present SC2: presence or absence of each species in the plot 0: absent 1: present SC3: presence or absence of each species in the plot 0: absent 1: present
Home \| Research \| Information Resources \| Publications \| Professional & Education Opportunities \| Staff & Contacts \| Site Map & Search @2008 The President and Fellows of Harvard College Faculty of Arts and Sciences of Harvard University Questions and comments e-mail – hfweb@fas.harvard.edu