Hemlock Woolly adelgid
description
Transcript of Hemlock Woolly adelgid
HEMLOCK WOOLLY ADELGID
Tennessee Division of Forestry
Background History of HWA Hemlock woolly adelgid (HWA) (Adelges
tsugae) is a non-native insect pest that kills native eastern and carolina hemlocks (Tsuga canadensis & Tsuga caroliniana)
HWA was first discovered in Virginia in 1951 and as of 2012 has spread to 18 eastern states where it has significantly altered or reduced native hemlock populations
Background History of HWA in Tennessee
In Tennessee HWA was discovered in Sevier & Blount counties in 2002 and has since spread west to the Cumberland Plateau
Much of the hemlock population in the Blue Ridge eco-region of our state has already been lost or is severely threatened by this pest
Since 2002, HWA has spread to 36 Tennessee counties
HWA Threats HWA is the single greatest threat to
hemlock health and sustainability in the eastern US and is comparable to Dutch Elm Disease and American Chestnut Blight in potential impacts
If left untreated, HWA can kill a hemlock tree within 3 to 7 years of infestation
HWA Threats Hemlock forests play a vital role in riparian areas as
they: - prevent erosion on steep banks which helps to prevent
disruptive water quality issues - provide shelter for many wildlife species - keeps water temperatures moderate in cold winter
months and cool during hot summers days for aquatic species
HWA can potentially destroy these values and forever change the forest landscape!!
Why Hemlocks are Important to Tennessee
Aesthetic Value Economic Value
Environmental Value Personal Value
HWA Spread Methods Wind Birds and animals Transplant of trees from
infested areas Purchasing infested nursery
stock People
Most Visible Sign of HWA
Healthy
Stages of Hemlock Decline
Slight defoliation Mortality
3 7
Years
How Does HWA Kill Trees? Nymphs and adults insert a
stylet near the base of needles and feed on sap and nutrients
May inject a saliva into the tree to disrupt plant growth
Multiply rapidly- no natural predators
Sheer numbers feeding on a hemlock results in loss of vigor and eventual death (3 to 7 years)
Biological Controls: Predator Beetles
Pros: Best chance for long-term
control of HWA Can be used on large
inaccessible areas Good for treating moderate
to heavy HWA infestations Three different species of
beetles are being raised at UT
Cons: Expensive: beetles can cost
between $2-$3 each & most areas require thousands of beetles for introduction
Successfully introduction requires extremely specific site conditions
Only nearby rearing facility is the University of Tennessee and for public lands only
Two companies in Pennsylvania and North Carolina are selling beetles for private landowners
Laricobius nigrinus beetle being release on state forest land
Chemical Information-Imidacloprid
Imidacloprid: For light to moderate infestation Treatment life is between 3-8 years,
depending on tree Must be kept out of direct sunlight
Chemical Information-Imidacloprid
Imidacloprid is a Neonicotinoid insecticide are synthetic derivatives of nicotine, an alkaloid compound found in the leaves of many plants in addition to tobacco.
Could affect honey bees and aquatic invertebrates
Treatment Methods Use: Soil Drench, Soil Injection, Stem Injection and Foliage Spray
Chemical Information-Dinotefuran
Dinotefuran (Safari): For moderate to heavy infestations Do not apply within 20 feet of direct water
source, or to areas where surface water is present or to areas below the mean high water mark
For trees in forests that are pollinated by bees or other invertebrates, make applications post-bloom
Chemical Information-Dinotefuran
Must be kept out of direct sunlight Treatment life is between 1-3 years,
depending on tree Could affect shrimp and aquatic
invertebrates Treatment Methods Use: Soil Drench, Soil
Injection, Foliage and Bark Spray
*Please be sure to read and follow all label instructions when using any pesticides.
Methods Available to Treat HWA
Soil Drench Soil Injection Stem Injection Foliage Spray or Basal Spray
Soil Drench Equipment
Kioritz Soil Injector
Soil DrenchingCons:
Have to move back leaf and duff litter to expose roots to drench
More room for chemical amount error
Should not be used on steep slopes
Can not be used at least 5 foot from a water source for Imidacloprid and 20 feet for Dinotefuran
Pros: Very easy to use Versatile system Lightweight Can use both HWA chemical
products for this system
Soil Drench Equipment
Soil InjectionPros:
Can give an accurate amount of chemical to a tree
Can use both HWA chemical products for this system
Versatile system
Cons: Sometimes injector clogs up
and must be cleaned and needs maintenance
Hard to find Kioritz Soil Injectors are no longer being produced but other soil injectors are becoming available
Can not be used at least 5 foot from a water source for Imidacloprid and 20 feet for Dinotefuran
NU-ARBOR 1-Two Root Injector
Kioritz Soil Injector
Stem InjectionPros:
Can be used by trees next to a water source
Can give a accurate amount of chemical to a tree
Less weight compared to other treatment methods
Cons: Can only use Imidacloprid
chemical in injector Equipment costs more
than other HWA treatment methods
Must drill holes in trees to apply chemical but newer systems are becoming less invasive
Creates wounds around the base of the tree
Trees need to have greater than 50% live crown left for successful treatment
Arbor-Jet Stem Injector
Bark Spray
Pros: Good for treating moderate
to heavy infestations No drilling holes in trees to
apply chemical
Cons: More potential for
chemical exposure and drift
Can only use Dinotefuran chemical in this system
Do not apply to wet bark, during rainfall or if rain is expected within 12 hours.
Can not be used within the 20 feet of a water source
D.B. Smith Contractor Series Sprayer
Foliage SprayPros:
Good for treating foliage on small hemlocks with trees less than 30 feet in height
Good for treating light-heavy infestations
Cons: Can not be used at least 5
foot from a water source for Imidacloprid and 20 feet for Dinotefuran
More potential for chemical exposure and drift
Best to begin applications before the onset of high pest populations
Foliar applications are best made in late spring or from July through September when the insect is not covered by protective wool
Field King™ Backpack Sprayer
Treating Light Infestation Full foliage, good green
color in needles Products-Imidacloprid,
Dinotefuran Methods-Soil injection,
soil drench, foliage spray and stem injection
Best time to treat-Spring and Fall but can be done year-round depending on weather and soil conditions
Treating Moderate Infestation Thinning foliage, poorer
color, needles starting to drop
Products-Imidacloprid, Dinotefuran
Methods-Soil injection, soil drench, foliage, bark spray and stem injection
Best time to treat-Spring and Fall but can be done year-round, depending on weather and soil condition
Treating Heavy Infestation Foliage very thin or
missing in places, gray green, die back is starting or occurring
Products-Imidacloprid, Dinotefuran
Methods-Soil injection, soil drench, bark spray and stem injection
Best time to treat-Spring and Fall but can be done year-round, depending on weather and soil condition
Equipment Cost of Each Method
Soil Dench Between $7.95-$8.18(One 5 gallon jug or one 48 ounce Nalgene bottle)
Stem Injection Between $394-$400(Hypo-Hatchet® Tree Injector or Arbor-Jet Quick Jet) Other systems cost up to $1,500 or more
Soil Injector Between $495-$1,700
(NU-ARBOR 1-Two Root Injector or HTI Soil Injector)
Foliage/Bark Spray Between $38.75-
$67.95(D.B. Smith Contractor Series Sprayer or 4-Gallon Capacity Field King™ Backpack Sprayer)
*Please note prices will vary with sales tax, shipping cost local availability and any extra accessories you may need to buy
Cost Comparison of Chemicals
Cost Range Per Unit (commonly sold sizes; not including shipping and handling)
Inches of Tree Diameter Treated Per Unit
Cost Range Per Inch of Tree Diameter (not factoring for double dosing trees ≥ 24
inches in diameter)
Generic Brands of 75% Water Soluble Imidacloprid (75% WSP/WSB)
$34-$50/pouch of 4 at 1.6g per bag
192 inches/pouch of 4 at 1.6g per bag
$0.17-$0.26/inch of diameter (when purchasing pouches of 4)
Generic Brands of 21.4-22.6% Flowable Imidacloprid (2F/2L) $105-$180/gallon Up to 3,840 inches/gallon $0.05-$0.14/inch of diameter
Imidacloprid Tablets(Cortect brand only) $112-$180/bottle of 250 125 inches/bottle of 250 $0.90-$0.1.44/inch of diameter
Imidacloprid 5% Injectable Chemical (Ima-Jet brand only) $250-$302/Liter 250 inches/Liter $1.00-$1.21/inch of diameter
Dinotefuran 20SG Soluable Granule (Safari brand only) $357-$390/3 pounds 468 inches/3 pounds $0.76-$0.85/inch of diameter
Steps for Private Landowners Treating HWA
1. Determine your goals and objectives for your forest as well as for your hemlocks. Treating your hemlocks should be a long term commitment that may involve multiple treatments. Developing a comprehensive forestry management plan is highly encouraged
2. Inspect trees to determine level of HWA infestation present: none, light, moderate or heavy.
3. Assess site conditions (soils, terrain, slopes and accessibility of site)
Steps for Private Landowners Treating HWA
4. Collect tree data (record for each trees dbh and number of trees per acre for site)
5. Based on steps 2-4, determine treatment strategy (chemical type, amount of chemical, labor and treatment method)
6. Estimated cost of Treatment
7. Develop long term budget for continue treatment for HWA
*NOTE: It is the user's responsibility to read and follow all label instructions when using any pesticide materials.
For more information or technical assistance please contact:
Heather Slayton615-218-4377
[email protected] visit
www.protecttnforests.org