uid=HFR,o=lter,dc=ecoinformatics,dc=org
all
public
read
doi:10.6073/pasta/2f32cf0b0a84f6890209b2547fa54b21
Tree Seed Dispersal in Hemlock Removal Experiment at Harvard Forest 2005
Sydne
Record
https://orcid.org/0000-0001-7293-2155
Aaron
Ellison
https://orcid.org/0000-0003-4151-6081
2023
English
Throughout the northeast, the hemlock woolly adelgid (Adelges tsugae) threatens eastern hemlock (Tsuga canadensis) through direct mortality resulting from infestation followed by defoliation and indirect mortality in the form of pre-emptive logging. The efficacy of regeneration of vegetation following hemlock decline depends upon advance regeneration of seedlings and saplings, seed dispersal, and recruitment. In this study, we investigated (1) whether the basic parameters of height of release and wind velocity affected seed dispersal distance and (2) tested the fit of a basic ballistic model of seed dispersal to empirical data in areas both with and without canopies. We collected empirical data from seed dropping and seed rain experiments at Harvard Forest. Height and wind velocity only affected seed dispersal distance in open areas. Predicted values of dispersal distance generated by the basic ballistic model did not provide a good fit to observed dispersal data. Poor fits of the ballistic model to the data were due to the model’s inability to account for rare, long distance dispersal events. More complex models with additional parameters are necessary to model non-localized seed dispersal.
hemlock
hemlock woolly adelgid
seed dispersal
wind
LTER controlled vocabulary
disturbance
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=hf120
Prospect Hill Tract (Harvard Forest), Simes Tract (Harvard Forest). Coordinates based on WGS84 datum.
-72.22
-72.17
+42.55
+42.47
200
420
meter
2005
2005
genus
Acer
species
platanoides
genus
Betula
species
lenta
genus
Quercus
species
rubra
genus
Tsuga
species
canadensis
complete
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
Seed Dropping Experiment
The open area data were collected in the parking lot of Shaler Hall on 28 of October 2005. The closed canopy data were collected in the forest at the Prospect Hill Tract on 18 November 2005. The study species for the seed dropping experiment were Acer platanoides L. (Norway maple) and Quercus rubra L. (red oak). Seeds were dropped at a range of heights between 0.5 m and 17.0 m. We recorded wind velocity simultaneously as seeds were released and the distance seeds traveled from the point of release.
Seed Rain Experiment
The study site was comprised of two 90 x 90 m adjacent plots that are part of the hemlock woolly adelgid, large-scale hemlock removal experiment at the Simes Tract of Harvard Forest. One plot consisted of a control stand (Plot 3) that is dominated by Tsuga canadensis L. (eastern hemlock) and the other plot (Plot 2) consisted of a commercially logged treatment in which all T. canadensis over 20 cm in DBH and all economically profitable hardwoods were logged and removed in the winter and spring of 2005. A total of 57 seed traps were placed every ten meters along three 180 m long transects that traversed the plots from east to west on 17 September 2005. Seeds were collected from traps every two weeks from 14 October to 13 November 2005. The design of the seed traps was biased towards collecting the light, wind dispersed seeds of B. lenta, which began dehiscing from trees in mid-October. Observed dispersal distances of seeds were calculated by mapping the location of trapped seeds in relation to the nearest B. lenta individual. Predicted values of dispersal distances were calculated using a basic ballistic model of seed dispersal.
Harvard Forest Long-Term Ecological Research
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.
hf120-01-maple.csv
maple
hf120-01-maple.csv
1566
c7f9c28599c395053abcf79ed370db56
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p12/hf120/hf120-01-maple.csv
canopy.type
canopy condition (open versus closed) at the location where we dropped seeds
Closed
closed canopy refers to a forested area in the Prospect Hill Tract
Open
open canopy refers to the parking lot behind Shaler Hall
height
height in meters at which we dropped each seed
meter
0.01
real
NA
missing value
wind.velocity
wind velocity in meters/second taken with a digital anemometer as we dropped each seed
metersPerSecond
0.01
real
NA
missing value
distance
distance in meters that each seed travelled from the point at which we dropped it
meter
0.01
real
NA
missing value
73
hf120-02-oak.csv
oak
hf120-02-oak.csv
1742
9a5807708692fb731abc48de48252db8
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p12/hf120/hf120-02-oak.csv
canopy.type
canopy condition (open versus closed) at the location where we dropped seeds
Closed
closed canopy refers to a forested area in the Prospect Hill Tract
Open
open canopy refers to the parking lot behind Shaler Hall
height
height in meters at which we dropped each seed
meter
0.01
real
NA
missing value
wind.velocity
wind velocity in meters/second taken with a digital anemometer as we dropped each seed
metersPerSecond
0.01
real
NA
missing value
distance
distance in meters that each seed travelled from the point at which we dropped it
meter
0.01
real
NA
missing value
81
hf120-03-birch.csv
birch
hf120-03-birch.csv
2244
ec6cb78715f10c10ba35be143777f3cd
1
\r\n
column
,
https://harvardforest.fas.harvard.edu/data/p12/hf120/hf120-03-birch.csv
date
date when we collected seeds off of seed traps
YYYY-MM-DD
transect
transect that seed trap was placed along
A
Transect A
B
Transect B
C
Transect C
distance
distance in meters of placement of seed trap along transect. Zero meters was at the
western edge of the Hemlock Removal Experiment plot 3. The transect extended east
through plot 3 til the eastern edge of the Hemlock Removal Experiment plot 2.
meter
1
natural
NA
missing value
seeds
number of seeds collected from a trap on a particular date
number
1
whole
NA
missing value
114
plot
community
short-term measurement
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf107
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf105
https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf106