uid=HFR,o=lter,dc=ecoinformatics,dc=org all public read doi:10.6073/pasta/4de496ce2e8e3d0ce1242edfd1a0b4bd Franklin Sullivan https://orcid.org/0000-0002-2499-8245 Mark Ducey https://orcid.org/0000-0002-2027-1188 Michael Palace https://orcid.org/0000-0002-3505-2906 David Orwig https://orcid.org/0000-0001-7822-3560 Researcher Bruce Cook Researcher 2023 English

In September and October 2013, variable radius plot sampling (Bitterlich, 1984) was completed within the extent of the ForestGEO plot. Thirty-nine randomly selected plots were located approximately using a handheld Garmin GPSmap 76CSx handheld GPS unit (error± approx. 5 m). Actual plot centers were recalculated post hoc by calculating the centroid of the UTMx,y locations of tagged trees in the Prospect Hill Tract plot space relative to the x,y locations of the same trees in the local coordinates of the variable radius plot. At each plot, a 4.59 m2/ha basal area factor prism was used to sample trees 5 cm and greater DBH; the sample trees thus represent a size-weighted sample of the full population of the trees over 5 cm DBH on the tract (Kershaw et al., 2016, ch. 9). At each sampled tree, we recorded species and tag number (except where they had fallen off or not been measured for census yet), as well as measured the distance and bearing from plot center, DBH, tree height, crown base height, and crown radius toward and away from plot center. This pair of crown radii can be used to estimate crown area without bias, irrespective of crown shape (Gregoire and Valentine, 1995). Crown radii and tree height measurements were made using a laser range finder with a viewfinder and integrated tilt sensor (DISTO D5, Leica Geosystems). Crown radii were measured by using the viewfinder to determine when the observer was under the dripline of the tree crown toward and away from plot center, and by measuring the distance to the stem using a laser range finder which was subsequently adjusted for the distance between stem face and stem center. Allometric equations for tree height, crown depth, and crown radius were developed in R (version 3.0.1) using a mixed effects modeling approach in the lme4 package. Developed equations were applied to MegaPlot census data. For more details on analysis and application, see Sullivan et al. 2017.

Bitterlich, W., 1984. The relascope idea: relative measurements in forestry, 1st ed. Commonwealth Agricultural Bureaux, Slough, UK. Gregoire, T.G., Valentine, H.T., 1995. A sampling strategy to estimate the area and perimeter of irregularly shaped planar regions. For. Sci. 41, 470–476. Kershaw Jr., J.A., Ducey, M.J., Beers, T.W., Husch, B., 2016. Forest Mensuration, fifth ed. Wiley, New York. Sullivan, F. B., Ducey, M. J., Orwig, D. A., Cook, B., Palace, M. W. 2017. Comparison of lidar- and allometry-derived canopy height models in an eastern deciduous forest. Forest Ecology and Management 406: 83-94.

Harvard Forest

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(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu https://ror.org/059cpzx98 pointOfContact 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. National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210. hf339-01-hf-tree-2013.csv Harvard Forest tree data hf339-01-hf-tree-2013.csv 59786 9b9ae3903f598ad28a49012ef682910f 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p33/hf339/hf339-01-hf-tree-2013.csv date date YYYY-MM-DD 1 day NA missing value plot randomly assigned name randomly assigned name NA missing value species genus/species 6 letter codes (4 genus, 2 species) genus/species 6 letter codes (4 genus, 2 species) NA missing value si.offset.e east offset relative to SW corner meter 0.0000001 real NA missing value si.offset.n north offset relative to SW corner meter 0.0000001 real NA missing value tree.easting calculated position from SW corner in UTM coordinates number 0.001 real NA missing value tree.northing calculated position from SW corner in UTM coordinates number 0.001 real sensor.est.e estimated easting position of plot center from tree position, distance and bearing from observer in UTM coordinates number 0.0001 real NA missing value sensor.est.n estimated northing position of plot center from tree position, distance and bearing from observer in UTM coordinates number 0.001 real NA missing value dbh diameter at breast height centimeter 0.1 real NA missing value height top tree height in meters, measured w/ hypsometer meter 0.1 real NA missing value cbh height in meters of the base of the crown meter 0.1 real NA missing value rad.in radius measured of tree crown towards plot center meter 0.01 real NA missing value rad.out radius measured of tree crown away from plot center meter 0.01 real NA missing value distance distance of tree pith from plot center meter 0.01 real NA missing value bearing azimuth from plot center to tree degree 1 natural NA missing value east.center easting component of position relative to plot center number 0.000000001 real NA missing value north.center northing component of position relative to plot center number 0.000000001 real NA missing value tag if available, MegaPlot tag number of tree if available, MegaPlot tag number of tree NA missing value 374 hf339-02-species.csv species codes hf339-02-species.csv 359 a5b3c10bc7a40f8ddbb4c5d345f67fb3 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p33/hf339/hf339-02-species.csv species.code species code species code NA missing value species.name genus and species name genus and species name NA missing value 14 biodiversity informatics plot short-term measurement https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf253