|
        Home | Contact
You are here: NJ Forest Service > Forest Health
Forest Health in New Jersey
State Forestry Services surveys New Jersey's forests both from the ground and the air for various insects and diseases. While hundreds of insects and diseases damage our forests, foresters suppress only those that spread quickly and will not weaken on their own. Often the worst pests and diseases are non-native and introduced to our forests accidentally. Without their native predators, these pests will thrive and spread.
Southern
Pine Beetle
(Dendroctonus frontalis)
  Details
This fast-moving bark beetle killed over 14,000 acres of southern NJ pines in 2010 alone.
Susceptible Species
SPB attacks
all species
of pine
including pitch, shortleaf, Virginia, white,
loblolly, and red.
Signs of Infestation
Pitch tubes, exit holes, fading crown, S-shaped galleries under bark
Affected Areas
Pine forests in southern New Jersey
More information Southern pine beetle from State Forestry Services
Gypsy
Moth
(Lymantria dispar)
Details
Larvae feed from May-June. Often confused with Eastern tent caterpillar. The high gypsy moth population
in
New Jersey can be attributed to reduced activity
of the fungal parasite Entomophaga
maimaiga. The reduced activity is due to lack of
precipitation.
Susceptible Species
Prefers oaks and but also attacks many deciduous trees and shrubs
Signs of Infestation
Defoliation, oval egg masses, caterpillars
Affected Areas
Statewide
More information Gypsy moth from the US Forest Service
Hemlock
Woolly Adelgid
(Adelges tsugae) 
Details
Nymphs and adults feed on sap from the tree's twigs. This
insect has infested all 26,000 acres of Hemlock stands
to some
degree
in New Jersey.
Some hemlock stands have been destroyed, while others have
only low HWA infestations.
Susceptible Species
Eastern hemlock
Signs of Infestation
Egg masses, dying limbs
Affected Areas
Statewide
More information Hemlock woolly adelgid from the US Forest Service
Eastern Pine Looper
(Lambdina pellucidaria)
Details
After overwintering in the soil beneath the host tree, moths emerge in May and June to lay eggs on the tree's needles. By mid-summer, the larvae hatch and eat notches out of the needles.
Susceptible Species
Pine species
Signs of Infestation
Brown needles, defoliation
Affected Areas
Ocean and Eastern Burlington Counties
Emerald
Ash Borer
(Agrilus planipennis)
  Details
The invasive destructive insect, Emerald Ash Borer, has been found in nearby states Maryland, New York, and Pennsylvania.
Susceptible Species
White ash, green ash
Signs of Infestation
D-shaped exit holes, woodpeckers
Affected Areas
Not yet found in NJ
More information Emerald ash borer from the US Forest Service
Asian
Longhorned Beetle
(Anoplophora glabripennis)
Details
The larvae of this invasive species feeds on the heartwood
Susceptible Species
maples, willows, poplars, ash,
horse chestnuts, elm, and buckeye trees
Signs of Infestation
3/4" to 1 1/4" adults, 3/8" exit holes, oozing sap, sawdust
Affected Areas
Union and Middlesex Counties
More information Asian longhorned beetle from the US Forest Service
Sudden
Oak Death
(Phytophthora ramorum)
Details
Plant pathogen found in CA, OR, WA, FL, GA
Susceptible Species
75 Species including many oaks
Signs of Infestation
Brown leaves, large bleeding cankers
Affected Areas
Not yet found in NJ
More information Sudden oak death from the USDA APHIS
Bacterial Leaf Scorch
(Xylella fastidiosa)
Details
The bacterium
is transmitted to healthy trees by feeding leafhopper and
spittlebug insects
moving from diseased herbaceous plants, such as goldenrod,
blackberries, and clover, to healthy trees. This disease
continues to be a serious health threat to urban shade trees
in NJ.
Susceptible Species
Red, pin, and scarlet oaks, sycamore, elm.
Signs of Infestation
Brown discoloration along leaf margins.
Affected Areas
South-western New Jersey
More information Bacterial leaf scorch from the US Forest Service
Beech Bark Disease
(Nectria coccinea)
  Details
Fungus invades through bark wounds created by aphid-like insects
Susceptible Species
American Beech, European Beech
Signs of Infestation
Sparse foliage, woolly scales, ooze on trunk, small red fungal fruiting bodies
Affected Areas
Northern New Jersey
More information Beech bark disease from the US Forest Service
Scarlet Oak Sawfly
(Caliroa quercuscoccineae)
Details
Repeated defoliation may affect vigor or kill the tree
Susceptible Species
Red and white oaks
Signs of Infestation
Skeletonized or transparent leaves, defoliation starting in upper crown, larvae feeding on leaves
Affected Areas
Northern New Jersey
More information Scarlet oak sawfly from the USDA Forest Service
Thousand Cankers Disease
Details
A tiny bark beetle, the walnut twig beetle when combined with the Geosmithia fungus result in tree dieback and mortality. Found as close as Bucks County, PA.
Susceptible Species
Black walnut
Signs of Infestation
Branch dieback, many small cankers on branches and bole, tiny bark beetles, circular or oblong cankers under bark, tiny entrance and exit holes
Affected Areas
Not found in NJ yet
More information Thousand cankers disease from the USDA Forest Service
|
