Forest Pests that have the Potential to Impact the Adirondack Forest

Forest Pest Damage and Effects	Trees Species Affected	Damage and Effects	Tree Signs & Symptoms	Year detected in US	Likely Original Source of Pest	Future	Likely Method to Invade Adirondacks
Asian Longhorned Beetle Anaplophora glabripennis	Sugar, red, silver & Norway maples, boxelder. Also: alder, birches, elms, horsechestnut, poplar & willows	Beetle larvae girdle and weaken trees by boring into stem and branches destroying phloem and xylem.	Tree decline with death in 2-5 years.	NY-1995 IL-1997 Likely arrival in 1980’s	Contaminated solid wood packaging material (pallets and shipping crates) from Asia.	NY outcome dependent on eradication efforts and strong public policy. No longer found in Illinois.	Transport of larvae in contaminated firewood and spread to surrounding forests.
Emerald Ash Borer Agrilus planipennis	Ash (Fraxinus spp.)	Beetle larvae girdle trees by boring beneath the bark destroying phloem and xylem.	Tree decline with death in 2-3 years.	MI-2002 Likely in state for 6-10 years prior to reported date.	Contaminated solid wood packaging materials (pallets and shipping crates) from Asia.	Eradication efforts ongoing, but still expanding range east across the Great Lake region. Currently 150 miles west of NYS (350 mile west of Adk’s) May enter NYS in the next several years.	Southern and westerly winds carrying beetle or by transport of larvae in contaminated firewood and spread to surrounding forests.
Sudden Oak Death (Oomycetes) Phytophthora ramorum	Oaks, coastal redwoods, Doug-fir and many other species including ornamentals (rhododendron)	Causes foliage wilting and cankers which affects phloem and xylem transport by clogging vessels.	Tree decline within 1-3 years.	CA-1995 [Europe ‘93]	Previously unknown species, with 2 strains – one from California and the other from Europe - both exist on the US west coast.	Numerous cases where contaminated nursery stock was transported to the east coast. Northern red oaks are reported to be susceptible.	Transport of contaminated nursery stock with spread to surrounding forests.
Hemlock Woolly Adelgid Adelges tsugae	Hemlocks - both eastern and Carolina hemlocks	Adults feeds on phloem of small twigs.	Tree decline with in 2-5 years.	OR-1924 VA-1951 PA-1969	Asia, although long resident in western North America.	Parasitic beetles have been introduced since 1999 with some positive results (or was it the effect of the wet weather?).	Sticky white wooly masses of adult, nymphs, or eggs transported by sticking to and transported by animals (esp. birds), cars and campers. Also transported by infected nursery stock and by wind.

Prepared by B. Grisi, NYS Adirondack Park Agency, with revisions by NYS DEC, Cornell Cooperative Extension and SUNY ESF, May 2005.
Notes:
1. SOD caused by Phytophthora ramorum. Phytophthora, is a family of notorious pathogens linked to the Irish potato famine and the die-off of Port Orford cedars in Oregon.

Forest Pests that have Significantly Impacted Adirondack Forest

Forest Pest	Trees Species Affected	Damage and Effects	Tree Signs & Symptoms	Method of Spread	Year Detected in US	Likely Original Source of Pest	Outcome
Beech Bark Disease (scale Cryptococcus fagisuga and fungus Nectria coccinea combination)	American beech	The disease results when bark, attacked and altered by the beech scale, is invaded by the Nectria fungus which affects cambium layer to cause general health decline of infected trees.	White wax secreted by the beech scale shows on the bark as the first sign of the disease followed by roughened areas of bark and slow steady tree decline.	Spores transported by wind and animals.	ME - 1932 WV - 1980 OH - 1985 MI - 2001	First identified in Europe in 1849. Accidentally spread to Nova Scotia in 1890 and from there, to the Canadian Maritime Provinces and Maine.	Widespread decline and mortality of beech in the northeastern US forests. Most all beech trees in the Park, greater than 4 inch dbh, have BBD, but continue to be a significant component of the deciduous forest. BBD significantly reduces tree vigor, growth, form, mast production and commercial value.
Chestnut Blight (fungus) Cryphonectria parasitica	American chestnut	Fungus causes sunken canker which girdles the tree.	Typically kills everything above canker in one year.	Fungus spreads very rapidly in nature by wind, rain, birds, and other animals.	NYC-1904	Asian fungus first reported in NYC in 1904.	It was reported that 1 in 4 trees in the Eastern Deciduous Forest were Chestnuts prior to the Blight. By 1950 nearly all mature American chestnuts trees were killed. American chestnut trees still exist in the Park but all succumb to the Blight by the time they reach about 4 inches dbh.
Dutch Elm Disease (fungus) Ophiostoma ulmi	American elm	Fungus grows and reproduces in the xylem and blocks water movement in the tree.	Leaves start to wilt and turn brown. The disease kills individual branches and eventually the whole tree in 1 to 5 years.	The elm bark beetle feeds on trees and transports the fungus from tree to tree. Also by root contact in the soil.	1930’s	Diseased logs from Europe.	Most all mature American elm trees in the US were killed. Only young trees and isolated pockets of mature trees exist. Most American elms succumb to the DED by the time they reach about 4 inches dbh.

Forest Pests that Continue to Significantly Impact Adirondack Forest

Forest Pest	Trees Species Affected	Damage and Effects	Tree Signs & Symptoms	Method of spread	Year detected in US	Likely Original Source of Pest	Result
Armillaria (fungus) Armillaria spp.	Hundreds of species	Root fungus lives as a parasite on living hosts. Affects phloem and xylem transport and causes general health decline in infected trees.	White mycelial mats beneath bark. Loss of foliage (flagging) on upper branches.	Natural component of temperate and tropical forests. [ Also exists as a saprophyte on dead woody material ]			May be symptomatic of ‘maple decline.’ Infected trees may succumb quickly or live on in a weaken state.
Common Pine Shoot Beetle Tomicus piniperda	Scots, white, red, and jack pines with spruce, fir and larch as alternative hosts	Adult beetles enter one-year-old or current year shoots in the upper branches to feed, hollowing out 1-4 inches of the shoot, killing the shoot.	Infected branch shoots bend at the point of entry, yellow and eventually break off.	Adult beetles are weak flyers, but are transported by wind	OH - 1992	Native to Europe and Asia	Exists from Great Lake States to NY – all under active quarantine to limit spread. If infected, the destroyed tip shoots may damage tree form and future growing stocks.
Gypsy Moth Lymantria dispar	Oaks are the preferred hosts, but also: apple, basswood, birch, poplar and willow	Caterpillar feeds on foliage and weakens trees by defoliation. Several years of repeated defoliation stresses trees and can lead to death.	After 2-3 years of defoliation some trees are weakened to a point where they cannot recover. As food sources dwindle, GM populations crash (with the help of introduced parasites) and recovery of the healthier trees occurs. Tree growth is significantly reduced during periods of defoliation.	Long distance spread occurs when egg masses are transported by vehicles. Short distance spread results when small caterpillars are blown by the wind.	MA -1869 Accidentally reintroduced several times with slightly different strains	Europe and Asia Introduced to develop a strain of silk moth that was resistant to disease to begin a commercial silk industry.	Over 20 parasites introduced to control GM. After a significant outbreak, forest composition is altered to less-susceptible tree species (i.e. fewer oaks). Has the potential to be a significant pest in areas where there are large concentrations of oaks. Largely controlled by an introduced insect pathogen, Entomophaga mamaiga
Forest Tent Caterpillar Malacosoma disstria Hubner	Aspen and sugar maples preferred – many other species also.	Caterpillar feeds on foliage and weakens trees by defoliation. Several years of repeated defoliation stresses trees and can lead to death.	Outbreaks typically last 3 years, then subside due to diminished food sources and a surge of native predators, parasites and disease. Although defoliation kills few trees, tree growth is significantly reduced during periods of defoliation.	Adult moths are transported by wind.	Native insect	Reported in colonial times	Outbreaks are cyclic, occurring every 10-20 years. A significant outbreak is occurring in St. Lawrence County and is ‘blowing’ east into the Park.

Prepared by B. Grisi, NYS Adirondack Park Agency, with revisions by NYS DEC, Cornell Cooperative Extension and SUNY ESF, May 2005.
Notes:
1. Beech bark disease, chestnut blight and Dutch elm disease, reported in prior chart, are still active in the Park.
2. Healthy trees are able to resist pest attacks for a longer period of time. Trees in a weakened condition from drought or other pest problems will succumb quickly.
3. Forest pests active in the Park include: anthracnose, armillaria, ash yellows, Asian longhorn beetle, bark beetles, beech bark disease, brown spruce longhorn beetle, cedar longhorn beetle, cedar-apple rust, common pine shoot beetle, cytospora canker, diplodia tip blight, eastern tent caterpillar, elm spanworm, elongate hemlock scale, emerald ash borer, fall cankerworm, fall webworm, forest tent caterpillar, hemlock looper, hemlock wooly adelgid, hypoxylon canker, leafspot, nun moth, oak wilt, peach bark beetle, pear thrips, pine false webworm, red pine decline, red pine shoot moth, Siberian moth, sirex woodwasp, spring cankerworm, spruce bark beetle, spruce budworm, spruce canker, tar spots, white pine weevil, white pine rust....

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