The Role of Citizen Scientists in Monitoring the Hemlock Woolly Adelgid (Adelges tsugae) in New Hampshire

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The Role of Citizen Scientists in Monitoring
the Hemlock Woolly Adelgid (Adelges tsugae) in
New Hampshire

• Debra Kimball (dlk_at_cisunix.unh.edu)
• M.S. Graduate, Environmental Education
• Department of Education
• University of New Hampshire

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• The Hemlock Ecosystem
• Eastern hemlock is one of the most shade
  tolerant and long lived tree species in the E.
  US.
• Hemlock is usually located on northern
  exposures, steep riparian slopes, and edges of
  wetlands
• Provides critical habitat for many plant and
  animal species
• Important in maintaining aquatic habitat,
  shading streams, regulating stream flow,
  moderating water temperatures, and shading
  vernal pools
• black throated green and blackburnian warbler,
  and acadian flycatcher primarily associated with
  hemlock forests
• winter shelter for deer and other mammals
• Stream water quality affected as hemlock stands
  die near riparian areas gt increased N leaching

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Problem

• The hemlock woolly adelgid (Adelges tsugae) is a
  small aphid-like insect that has caused extensive
  damage to eastern hemlock (Tsuga canadensis)
  stands from Georgia to Massachusetts.
• New Hampshire currently relies on the public
  to recognize HWA infestation and report it to the
  county forester, DES Division of Forests and
  Lands, or UNH Cooperative Extension

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Range of HWA Infestation
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• Biology of A. tsugae
• The hemlock woolly adelgid is parthenogenetic
  (only females occur)
• Produces 2 generations/year
• Sistens-9 month cycle, progrediens- 4 month cycle
• Together they lay about 200 eggs/year
• Best time to see woolly ovisacs between November
  and June
• Feeds during cooler part of year inactive in
  summer months
• injects stylet into xylem ray paremchyma cells,
  likely injecting a toxic saliva
• Reddish brown nymphs can be carried to other
  trees via wind and animals
• Causes rapid desication and foliage discoloration

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Hemlock Woolly Adelgid - Depletes needle of
stored nutrient supplies and photosynthate
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Field and Lab Measurements
Hemlock Health New Growth Foliar
Transparency Dieback Live Crown Ratio
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Hemlock Woolly Adelgid Life Cycle
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Heavy infestation
Note grey foliage
Adelgid ovisacs on twig at base of needle
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Hemlock Decline
Productivity Reduced Needles desiccate and
drop Dieback of limbs and entire branches
Mortality typically within 4-6 years
Widespread mortality expected
J. Pontius 5/04
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Hemlock Decline Rating System
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Hypotheses

• Citizen scientists will be able to monitor for
  the presence of hemlock woolly adelgid through
  out the state of New Hampshire using simple
  protocols
• Student groups can provide reliable ground truth
• for hemlock foliar health
• Student data will find a relationship between
  geographic and site location(slope and aspect) of
  a stand and infestation rates or hemlock health

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Objectives

• Develop training protocols to collect data for
  a state monitoring system of HWA
• monitor stands for the presence or absence of
  HWA, growth rates, foliar health, and site
  characteristics
• Determine accuracy of plant stress glasses in
  detecting damaged needles and compare to
  hyperspectral data
• Determine the relationship between geographic
  and site location(slope and aspect) of a stand
  and infestation rates or hemlock health

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Methods

• 1. Select ten schools/groups to monitor the
  health of their hemlock stands by determining
• Location, GPS coordinates
• Presence of HWA or other pests
• (Report any occurrence of HWA to State DES or
  UNH Extension)
• Size and composition of stand
• Select 5 trees to monitor overall health
  (include height, DBH, canopy closure, live
  crown ratio, new needle growth, stress glasses
  results)
• Slope and Aspect

• 2. Acquire Landsat TM satelite datasets and
  hyperspectral datasets (pre and post infestation)
• Have students compare above datasets to yearly
  ground truth data
• 3. Develop a Hemlock Health monitoring guide for
  easier identification of signs of HWA and other
  hemlock pests
• Send out printed copies to selected schools and
  put on Forest Watch and DES? websites

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• Anticipated results and summary
• A citizen scientist monitoring system for the
  presence of hemlock woolly adelgid and hemlock
  foliar health through out the state of New
  Hampshire will assist researchers
• Ground truth data for hemlock foliar health
  will be valid and useful in checking remotely
  sensed data (Forest Service)
• Student data may find a relationship between
  geographic and site location(slope and aspect) of
  a stand and infestation rates or hemlock health

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Websites of Interest

• http//www.fs.fed.us/na/morgantown/fhp/hwa/other_l
  inks.htm main site
• http//www.fs.fed.us/na/morgantown/fhp/hwa/pdfs/mc
  clure_hwa.pdf
• http//na.fs.fed.us/wv/hwa/ bibliography
• Contact in NH- 603/271-7858

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Pawtuckaway State Park, NH

• Unless an effective biological or chemical
  control is found that can be released on a
  massive scale that coincides with the range of
  HWA, hemlock may be eliminated across broad
  portions of its range in a few decades (Orwig
  and Foster 1999)

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Timeline