uid=HFR,o=lter,dc=ecoinformatics,dc=org all public read doi:10.6073/pasta/354ae980bb525f356ffe39073ecc584d David Foster https://orcid.org/0000-0003-1171-3762 Audrey Barker Plotkin https://orcid.org/0000-0002-4473-9785 Ann Lezberg Researcher David Orwig https://orcid.org/0000-0001-7822-3560 Researcher 2023 English

Most of the central New England landscape was cleared for agriculture in the mid-19th century and then naturally reforested into "secondary forests" with the abandonment of agricultural land. Some sites, often poorly drained, remained forested, but were usually subjected to intensive fuelwood cutting or logging and are termed "primary forests." The Hemlock Woodlot was never cleared for agriculture, but has a history of cutting and natural disturbance. The hemlock woodlot is located in the center of Harvard Forest's Prospect Hill Tract, adjacent to a spruce-blackgum swamp. Soils are moist and rocky, with a thick organic layer. Hemlock dominates tree species composition (62% by basal area), with hardwoods and scattered large white pine comprising the remainder. Most of the trees are 100-150 years old, with a few hemlock trees up to 230 years old. While the site was never cleared for agriculture, it was logged several times and chestnut blight removed a chestnut-dominated overstory in the 1910s. The 0.72 ha stem-mapped plot is at the center of a 4-ha hemlock-dominated forest. This plot serves as a major reference site and is part of a network of hemlock forests that are being intensively sampled as the hemlock woolly adelgid arrives.

hemlock land use permanent plots tree maps vegetation dynamics LTER controlled vocabulary populations disturbance land use LTER core area Harvard Forest HFR LTER USA HFR default

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.

Creative Commons Zero v1.0 Universal https://spdx.org/licenses/CC0-1.0.html CC0-1.0 https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf031 Prospect Hill Tract (Harvard Forest). Coordinates based on WGS84 datum. -72.18 -72.18 +42.54 +42.54 355 355 meter 1989 2019 genus Tsuga species canadensis eastern hemlock ongoing Information Manager Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 hf-im@lists.fas.harvard.edu Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu

In 1990, the 120m x 60m plot was established with a 10m x 10m grid. The long axis of the plot runs approximately East-West and the 0,0 point is the northwest corner. All trees greater than or equal to 5 cm dbh were mapped using a technique in which inter-tree distances were measured to the nearest centimeter (Boose, E.R., E.F. Boose and A.L. Lezberg. 1998. A practical method for mapping trees using distance measurements. Ecology 79:819-827). For each tree, species, canopy position, health, and diameter were recorded. Trees with multiple stems originating from a single base were measured as separate individuals if the stems forked at less than 1.3m high. Tree diameter and condition was re-measured in 1999, 2009, 2014 and 2019; hemlock vigor was also recorded. In 2002, sapling density and understory cover was sampled in three 20x20m subplots in or adjacent to the stem-mapped plot. In 2002 a nitrogen cycling study was initiated in the same three 20m x 20m plots. Hemlock woolly adelgid was detected on 20% of the hemlock trees examined in 2009. In 2014, adelgid infested 98% of hemlock trees examined, and the forest canopy was noticeably thinning.

Harvard Forest

324 North Main Street Petersham MA 01366 USA

(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. hf031-01-tree.csv tree data hf031-01-tree.csv 106831 40140cf9f498fe6df857b820ae5569e9 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p03/hf031/hf031-01-tree.csv tree tag number (#1-744 present in 1989; 800 and up recruited in 1999, 2009 or 2014) tree identifier x x-coordinate within grid (meter; 0,0 is northwest corner; X is the 60m axis of the plot) meter 0.01 real NA missing value y y- coordinate within grid (meter; 0,0 is northwest corner; Y is the long axis of the plot) meter 0.01 real NA missing value cc canopy class CD codominant D dominant I intermediate S suppressed spec species code ACRU Acer rubrum BEAL Betula alleghaniensis BELE Betula lenta BEPA Betual papyrifera CADE Castanea dentata FAGR Fagus grandifolia HAVI Hamamelis virginiana PIRU Picea rubens PIST Pinus strobus QURU Quercus rubra TSCA Tsuga canadensis UNK unknown dbh90 diameter at breast height in 1990 centimeter 0.1 real NA missing value cond89 tree condition in 1989 D dead L living M moribund cond93 tree condition in 1993 D dead L living M moribund dbh99 diameter at breast height in 1999 centimeter 0.1 real NA missing value cond99 tree condition in 1999 D dead G tree could not be located L living M moribund vigor99 tree vigor in 1999 1 0-25% foliar loss 2 25-50% foliar loss 3 50-75% foliar loss 4 75-99% foliar loss 5 dead dbh09 diameter at breast height in 2009 centimeter 0.1 real NA missing value cond09 tree condition in 2009 D dead L living vigor09 tree vigor in 2009 1 0-25% foliar loss 2 25-50% foliar loss 3 50-75% foliar loss 4 75-99% foliar loss 5 dead hwa09 presence/absence of hemlock woolly adelgid in 2009, assessed on two branches. Only trees with branches within reach were assessed (49 of the 309 live hemlocks in the plot in 2009) 1 present 0 absent dbh14 diameter at breast height in 2014 centimeter 0.1 real NA missing value cond14 tree condition in 2014 D dead L living vigor14 tree vigor in 2014 1 0-25% foliar loss 2 25-50% foliar loss 3 50-75% foliar loss 4 75-99% foliar loss 5 dead hwa14b1 presence/absence of hemlock woolly adelgid in 2014, first branch. Only trees with branches within reach were assessed (41 of the 284 live hemlocks in the plot in 2014) 1 present 0 absent hwa14b2 presence/absence of hemlock woolly adelgid in 2014, second branch. Only trees with branches within reach were assessed (41 of the 284 live hemlocks in the plot in 2014) 1 present 0 absent ehs14 presence/absence of elongate hemlock scale. Only trees with branches within reach were assessed (41 of the 284 live hemlocks in 2014) 1 present 0 absent cond16 tree condition in 2016 D dead L living vigor16 tree vigor in 2016 1 0-25% foliar loss 2 25-50% foliar loss 3 50-75% foliar loss 4 75-99% foliar loss 5 dead hwa16b1 presence/absence of hemlock woolly adelgid in 2016, first branch. Only trees with branches within reach were assessed (41 of the 271 live hemlocks in the plot in 2016) 1 present 0 absent hwa16b2 presence/absence of hemlock woolly adelgid in 2016, second branch. Only trees with branches within reach were assessed (41 of the 271 live hemlocks in the plot in 2016) 1 present 0 absent ehs16 presence/absence of elongate hemlock scale. In 2016 Only trees with branches within reach were assessed (41 of the 271 live hemlocks in 2016) 1 present 0 absent dbh19 diameter at breast height in 2019 centimeter 0.1 real NA missing value cond19 tree condition in 2019 D dead L living vigor19 tree vigor in 2019 1 0-25% foliar loss 2 25-50% foliar loss 3 50-75% foliar loss 4 75-99% foliar loss 5 dead hwa19b1 presence/absence of hemlock woolly adelgid in 2019, first branch. Only trees with branches within reach were assessed (28 of the 244 live hemlocks in the plot in 2019) 1 present 0 absent hwa19b2 presence/absence of hemlock woolly adelgid in 2019, second branch. Only trees with branches within reach were assessed (14 of the 244 live hemlocks in the plot in 2019) 1 present 0 absent ehs19 presence/absence of elongate hemlock scale in 2019, first branch. Only trees with branches within reach were assessed (28 of the 244 live hemlocks in the plot in 2019) 1 present 0 absent megatag tree tag number for those trees that fall within the 35-ha Forest Dynamics Plot tree tag number note notes from 1989, 1993 and 1999 notes from 1989, 1993 and 1999 note2009 notes from 2009 notes from 2009 note2014 notes from 2014 notes from 2014 note2019 notes from 2019 notes from 2019 767 invasive plot long-term measurement https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf029 https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf048 https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf083