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Regional pressure

Regional Pest Alert Map

Where the major pests and diseases pressuring trees are established across the lower 48, how severe each one is, and when it peaks. Live alerts drop on when new detections and quarantines hit the news. Every marker links straight to diagnosis and treatment.

Pest pressure

66 hotspots across 22 pests & diseases · 35 live alerts

SevereHighModerateLowLive alert
AlabamaArizonaArkansasCaliforniaColoradoConnecticutDelawareDistrict of ColumbiaFloridaGeorgiaIdahoIllinoisIndianaIowaKansasKentuckyLouisianaMaineMarylandMassachusettsMichiganMinnesotaMississippiMissouriMontanaNebraskaNevadaNew HampshireNew JerseyNew MexicoNew YorkNorth CarolinaNorth DakotaOhioOklahomaOregonPennsylvaniaRhode IslandSouth CarolinaSouth DakotaTennesseeTexasUtahVermontVirginiaWashingtonWest VirginiaWisconsinWyoming

Hotspots are the established range centroids from the Pest & Disease library. Hover or tap a marker for detail, click through for treatment. Live alerts current as of Aug 23, 2026.

Live alerts

35 recent developments

HighQuarantine
Asian longhorned beetle quarantine boundaries revised in Charleston and Dorchester counties, SC

Clemson University announced quarantine boundary revisions in Charleston and Dorchester counties effective August 23, 2026, expanding the Hollywood quarantine area and reducing the Mount Pleasant area based on survey results.

Charleston and Dorchester counties, SC
Aug 23, 2026Asian Longhorned Beetle
HighNew detection
First known oak wilt case in Monroe County found in town of Greece, New York

New York DEC confirmed oak wilt in a red oak in the town of Greece, Monroe County, in mid-June 2026. Officials removed the infected tree and are monitoring nearby oaks near English Road and Vintage Lane.

Town of Greece, Monroe County, NY
Jul 24, 2026Oak Wilt
HighNew detection
Elm zigzag sawfly first detected in Michigan in St. Clair County

Michigan MDARD confirmed the state's first detection of elm zigzag sawfly in St. Clair County on July 21, 2026, identified from samples submitted by an arborist via the Midwest Invasive Species Information Network.

St. Clair County, MI
Jul 21, 2026Michigan EGLE / MDARD
HighRange expansion
Aerial spongy moth treatments planned across four northern Minnesota counties

Minnesota Department of Agriculture announced aerial treatments for spongy moth infestations in Aitkin, Carlton, Pine, and St. Louis counties starting July 14, 2026, targeting confirmed outbreak sites in northern Minnesota forests.

Aitkin, Carlton, Pine, and St. Louis counties, MN
Jul 14, 2026Spongy Moth
HighRange expansion
Southern pine beetle outbreaks continue on Cape Cod and islands, Massachusetts

Southern pine beetle outbreaks ongoing since 2023 are continuing in 2026 on Cape Cod, Martha's Vineyard, and Nantucket, targeting pitch pine. Officials urge reporting of suspected infestations amid continued bark beetle pressure.

Cape Cod, Martha's Vineyard, and Nantucket, MA
Jul 10, 2026Southern Pine Beetle
HighNew detection
Spotted lanternfly confirmed in Jackson County, Michigan

On July 10, 2026, Michigan conservation leaders confirmed spotted lanternfly in Jackson County as well as Lenawee, Macomb, Monroe, Oakland, and Wayne counties, reflecting continued range expansion in southeastern Michigan.

Jackson County, MI
Jul 10, 2026Spotted Lanternfly
HighNew detection
First mass spotted lanternfly sighting of 2026 reported in Bristol, Tennessee

On July 6, 2026, WCYB reported the first mass sighting of spotted lanternfly in Bristol, Sullivan County, Tennessee. Tennessee Department of Agriculture has officially detected SLF in six Tennessee counties so far in 2026.

Bristol, Sullivan County, TN
Jul 6, 2026Spotted Lanternfly
HighNew detection
EAB detected north of Mapleton in Cass County, North Dakota

On July 2, 2026, North Dakota Forest Service confirmed a second EAB detection in Cass County, north of Mapleton and more than 12 miles from the first find in Fargo, indicating local range expansion.

North of Mapleton, Cass County, ND
Jul 2, 2026Emerald Ash Borer
HighRange expansion
Spotted lanternfly now documented in 56 of 67 Pennsylvania counties

As of mid-2026, spotted lanternfly has been documented in 56 of Pennsylvania's 67 counties, showing continued spread across the state since the pest's first detection in Berks County in 2014.

Pennsylvania (statewide, 56 counties)
Jul 1, 2026Spotted Lanternfly
HighNew detection
Spotted lanternfly recorded for first time in Marion County, Ohio

On July 1, 2026, the first spotted lanternfly sighting in Marion County, Ohio was reported. Ohio is under a statewide SLF quarantine, and the insect continues to appear in new locations statewide.

Marion County, OH
Jul 1, 2026Spotted Lanternfly
HighRange expansion
Spotted lanternfly fully established throughout Fairfax County, Virginia

Fairfax County reports that spotted lanternfly, first detected in western Fairfax County in 2022, is now found throughout the county. Officials state that sighting reports are no longer needed due to the established population.

Fairfax County, VA
Jul 1, 2026Spotted Lanternfly
HighRange expansion
Emerald ash borer confirmed in Newberg, Tualatin, and Silverton, Oregon

Oregon officials confirmed EAB in three new locations within the existing multi-county quarantine zone: Newberg (Yamhill County), Tualatin (Washington County), and Silverton (Marion County). Two heavily infested ash trees and six with early signs were found in a Newberg parking lot.

Newberg, Yamhill County, OR
Jun 23, 2026Emerald Ash Borer
HighRange expansion
Spotted lanternfly populations confirmed across southeastern Michigan including Jackson County

MDARD confirmed spotted lanternfly populations across southeastern Michigan, including parts of Jackson County, expanding beyond earlier localized detections. More than 100 locations have been monitored since the first Michigan detection in 2022.

Southeastern Michigan, including Jackson County, MI
Jun 22, 2026Spotted Lanternfly
HighRange expansion
Spotted lanternfly established across Fairfax County, Virginia; exponential growth phase noted

Fairfax County reports spotted lanternflies have proliferated across the D.C. region since arriving in Annandale in 2021. County experts describe the species as still in an exponential growth phase and urge residents to report and kill insects.

Fairfax County, VA
Jun 16, 2026Spotted Lanternfly
HighRange expansion
Southern pine beetle outbreak continues on Cape Cod, Martha's Vineyard, and Nantucket

Ongoing southern pine beetle outbreaks that began in 2023 are continuing in eastern Massachusetts, with pitch pine as the primary host on Cape Cod, Martha's Vineyard, and Nantucket. Activity increases as temperatures warm and reporting of suspected infestations is urged.

Cape Cod, Martha's Vineyard, and Nantucket, MA
Jun 5, 2026Southern Pine Beetle
HighNew detection
EAB confirmed for first time in Young, Montague and Clay counties, Texas

Texas A&M Forest Service detected emerald ash borer adults in monitoring traps in three new Texas counties, announced June 5, 2026. The finds expand EAB's known range in the state.

Young, Montague and Clay Counties, TX
Jun 5, 2026Emerald Ash Borer
HighQuarantine
EAB found in Willmar triggers emergency quarantine of Kandiyohi County, Minnesota

Minnesota Department of Agriculture confirmed EAB in Willmar, outside the prior quarantine area, and enacted an emergency countywide quarantine on June 2, 2026. Movement of firewood and ash material out of Kandiyohi County is now restricted.

Kandiyohi County, MN
Jun 2, 2026Emerald Ash Borer
HighQuarantine
Box tree moth found in Rio Grande triggers Cape May County boxwood quarantine

New Jersey confirmed box tree moth at residences in Rio Grande, Middle Township, Cape May County, in June 2026, placing the county under a boxwood quarantine restricting movement of plant material.

Rio Grande, Cape May County, NJ
Jun 1, 2026Cape May County Herald
HighNew detection
Infested grapevines sold at Napa Costco may have spread glassy-winged sharpshooter

Napa County officials warned on May 26, 2026 that grapevines sold at a Napa Costco between April 21 and May 26 may carry glassy-winged sharpshooter. Of 220 vines from a Fresno County nursery, 157 were unaccounted for and potentially planted across Napa County.

Napa, Napa County, CA
May 26, 2026Napa Valley Focus
HighQuarantine
Statewide spotted lanternfly quarantine in effect across all Maryland counties

The Maryland Secretary of Agriculture issued a quarantine order covering all 23 Maryland counties and Baltimore City. A March 2026 infestation ranking shows heavily infested areas in Baltimore City and central Maryland counties including Baltimore, Howard, and Prince George's.

Maryland (statewide)
Mar 1, 2026Spotted Lanternfly
HighQuarantine
Ohio implements statewide spotted lanternfly quarantine in February 2026

In February 2026, the Ohio Department of Agriculture implemented a statewide quarantine for spotted lanternfly following its spread across multiple counties. Trap installation at parks in Beavercreek, Greene County was planned for July 2026.

Beavercreek, Greene County, OH
Feb 1, 2026Spotted Lanternfly
HighQuarantine
Oak wilt quarantine district active in Ontario and Yates counties, New York

NYS DEC maintains an oak wilt quarantine district in parts of Ontario County towns Bristol, South Bristol, and Naples, and Yates County towns Middlesex and Italy, based on confirmed infection centers identified in 2025, restricting oak material movement.

Ontario and Yates counties, NY (Finger Lakes region)
Jan 1, 2026Oak Wilt
HighNew detection
EAB newly detected in Young, Montague, and Clay counties, Texas

Texas A&M Forest Service confirmed emerald ash borer in Young, Montague, and Clay counties after adult beetles were captured in monitoring traps. These are new county records expanding EAB's known presence in north-central Texas.

Young County, TX
Jan 1, 2026Emerald Ash Borer
HighNew detection
Spongy moth eradication proposed at sites in King and Pierce counties, Washington

Washington State Department of Agriculture proposed spongy moth eradication treatments west of Lake Youngs in King County and in the Lakewood area of Pierce County based on 2025 trapping data showing reproducing populations.

King County and Pierce County, WA
RecentSpongy Moth
ModerateNew detection
Box tree moth detected in Barnstable and Norfolk counties, Massachusetts

A June 26, 2026, UMass Extension update confirmed box tree moth in several Barnstable County communities and in Brookline, Norfolk County, prompting guidance for residents to report suspected finds.

Barnstable County and Brookline, Norfolk County, MA
Jun 26, 2026UMass Extension Landscape Message
ModerateSeasonal outbreak
Spotted lanternfly nymphs active statewide across Maryland under quarantine

A June 26, 2026 notice states spotted lanternfly nymphs are active throughout much of Maryland under an existing statewide quarantine. Residents are urged to destroy nymphs and report sightings to the Maryland Department of Agriculture.

Maryland (statewide)
Jun 26, 2026Spotted Lanternfly
ModerateSeasonal outbreak
Spotted lanternfly egg hatch and nymph activity documented in Worcester and Hampshire counties, MA

Massachusetts MDAR recorded SLF egg hatch in Worcester County as of May 8, 2026 and nymphs active on cultivated grapes in Belchertown, Hampshire County as of June 3, 2026. Nymph abundance increased on tree-of-heaven at UMass Amherst through June 17, 2026.

Worcester County, MA
Jun 19, 2026Spotted Lanternfly
ModerateRange expansion
Aerial treatments planned for three spongy moth management zones in Rochester, Minnesota

Minnesota Department of Agriculture designated three treatment blocks totaling over 36,000 acres in Rochester, Olmsted County, with aerial spraying scheduled for June 24-26, 2026. The treatments aim to slow spread of spongy moth populations in the city.

Rochester, Olmsted County, MN
Jun 18, 2026Spongy Moth
ModerateRange expansion
Spotted lanternfly now found in 56 of Pennsylvania's 67 counties

A Cumberland County notice reports spotted lanternfly has spread to 56 Pennsylvania counties. The pest feeds on sap from over 70 plant species and continues to expand since its initial Berks County detection in 2014.

Cumberland County, PA
Jun 1, 2026Spotted Lanternfly
ModerateSeasonal outbreak
Mountain pine beetle flight expected 2 to 4 weeks earlier than normal in Jefferson County, Colorado

Jefferson County officials observed late-stage mountain pine beetle larvae and pupae in ponderosa and lodgepole pine, with adult flight estimated around mid-June 2026, two to four weeks ahead of schedule. Landowners are advised to deploy verbenone repellent and inspect trees.

Jefferson County, CO
May 26, 2026Jefferson County, CO
ModerateRange expansion
EAB adult found in King City, expanding detections within Washington County, Oregon

An Oregon Department of Forestry specialist found a mature EAB adult in King City in early May 2026, the first detection in that community. King City is within the existing Washington County EAB quarantine zone established after Oregon's first find in 2022.

King City, Washington County, OR
May 25, 2026Emerald Ash Borer
ModerateSeasonal outbreak
Spotted lanternfly egg hatch reported in Worcester County, Massachusetts

Massachusetts Department of Agricultural Resources reported spotted lanternfly egg hatch began in Worcester County as of May 8, 2026. SLF now has established populations in multiple Massachusetts communities.

Worcester County, MA
May 8, 2026Spotted Lanternfly
ModerateQuarantine
Emergency spongy moth quarantine in effect in Coon Rapids, Anoka County, MN

A May 4, 2026 city alert for Coon Rapids, Minnesota, referenced an emergency quarantine in effect associated with invasive spongy moth, indicating a recent detection or elevated risk in Anoka County.

Coon Rapids, Anoka County, MN
May 4, 2026Spongy Moth
ModerateQuarantine
Spongy moth quarantine expanded to Green and Sawyer counties, Wisconsin

USDA APHIS and Wisconsin added Green County and Sawyer County to the spongy moth quarantine area effective May 1, 2026, expanding the regulatory footprint in the state.

Green County and Sawyer County, WI
May 1, 2026Spongy Moth
ModerateQuarantine
Spongy moth quarantine extended to Green and Sawyer counties, Wisconsin

On April 15, 2026, Wisconsin DATCP added Green County and Sawyer County to the state's spongy moth quarantine based on 2025 trapping data, restricting movement of firewood and nursery stock.

Green County and Sawyer County, WI
Apr 15, 2026Spongy Moth
Tracked pests & diseases

14 high-priority threats tracked

Browse all entries
Severe6 entries
Severe
Asian Longhorned Beetle
Anoplophora glabripennis
Localized eradication zones in the Northeastern and Midwestern United States
Peak: Adults active and emerging July through October
Worcester, MA · Long Island / NYC, NY · Clermont County, OH
pestView treatment
Severe
Dutch Elm Disease
Ophiostoma novo-ulmi
Throughout the native range of American elm in the United States and Canada
Peak: Symptoms appear late spring through summer; bark beetle vectors active spring–fall
Minneapolis, MN · Denver, CO · Toronto-border / Buffalo, NY
fungusView treatment
Severe
Emerald Ash Borer
Agrilus planipennis
Eastern, central, and expanding western United States and southern Canada
Peak: Adults fly and lay eggs late May through August; larvae feed under bark spring–fall
Detroit, MI (introduction epicenter) · Chicago, IL · Pittsburgh, PA
pestView treatment
Severe
Hemlock Woolly Adelgid
Adelges tsugae
Eastern United States from the southern Appalachians to New England
Peak: Woolly masses most visible fall through spring; two generations feed Oct–June
Great Smoky Mountains, TN/NC · Shenandoah / Blue Ridge, VA · Catskills / Hudson Valley, NY
pestView treatment
Severe
Oak Wilt
Bretziella fagacearum
Eastern and central United States; severe in the Upper Midwest and central Texas
Peak: Spring and early summer (high infection risk from fresh wounds April–July)
Austin / Texas Hill Country, TX · Minneapolis–St. Paul, MN · Madison, WI
fungusView treatment
Severe
Southern Pine Beetle (Pine Bark Beetle)
Dendroctonus frontalis
Southeastern United States, expanding north; related bark beetles range across the West
Peak: Multiple generations spring through fall; outbreaks peak in summer droughts
Atlanta / north GA · Pine Barrens, NJ · East Texas piney woods
pestView treatment
High8 entries
High
Armillaria Root Rot
Armillaria spp.
Throughout the United States and Canada; a widespread soilborne root pathogen
Peak: Decline visible in summer drought stress; honey mushrooms appear in fall
Seattle, WA · Sierra Nevada, CA · Asheville / southern Appalachians, NC
fungusView treatment
High
Bacterial Leaf Scorch
Xylella fastidiosa
Eastern, southeastern, and central United States (xylem-feeding insect vectors)
Peak: Symptoms most visible mid-summer to fall (July–October)
Washington, DC metro · Philadelphia, PA · Charlotte, NC
diseaseView treatment
High
Bronze Birch Borer
Agrilus anxius
Northern United States and Canada, throughout the range of birches
Peak: Adults emerge and lay eggs late May through July; larvae tunnel under bark
Minneapolis, MN · Denver, CO · Chicago, IL
pestView treatment
High
Fire Blight
Erwinia amylovora
Throughout the United States wherever rosaceous trees grow; worst in warm, humid spring weather
Peak: Bloom through early summer, during warm, wet, humid weather
Yakima Valley, WA · Kansas City, MO · Raleigh, NC
diseaseView treatment
High
Spongy Moth (formerly Gypsy Moth)
Lymantria dispar
Northeastern and Great Lakes United States and eastern Canada, spreading south and west
Peak: Caterpillars feed and defoliate May–June; egg masses laid mid-summer overwinter
Hartford / central CT · Boston, MA · Grand Rapids, MI
pestView treatment
High
Spotted Lanternfly
Lycorma delicatula
Mid-Atlantic and Northeastern United States, spreading west and south
Peak: Nymphs spring–summer; conspicuous winged adults July–November; eggs overwinter
Reading / Berks County, PA (US epicenter) · Philadelphia, PA · Newark / northern NJ
pestView treatment
High
Thousand Cankers Disease
Geosmithia morbida (vectored by Pityophthorus juglandis)
Western United States and pockets of the East and Midwest where black walnut grows
Peak: Beetles active and galleries expand spring through fall; dieback shows in summer
Denver / Front Range, CO · Knoxville, TN · Boise, ID
fungusView treatment
High
Verticillium Wilt
Verticillium dahliae / Verticillium albo-atrum
Throughout the United States; a soilborne fungus persisting for years in soil
Peak: Symptoms appear in summer, often after heat or drought stress (June–September)
Columbus, OH · Minneapolis, MN · Portland, OR
fungusView treatment
Moderate6 entries
Moderate
Anthracnose
Apiognomonia / Discula / Colletotrichum spp.
Throughout the United States; worst in regions with cool, wet spring weather
Peak: Spring, during cool, wet, rainy weather at and just after leaf-out
Portland, OR · Washington, DC · Nashville, TN
fungusView treatment
Moderate
Apple Scab
Venturia inaequalis
Cool, humid regions of the United States and Canada, especially the Northeast and Upper Midwest
Peak: Primary infections in cool, wet spring weather (bud break through early summer)
Hudson Valley, NY · Grand Rapids, MI · Boston, MA
fungusView treatment
Moderate
Bagworms
Thyridopteryx ephemeraeformis
Eastern and central United States, particularly the Midwest and Southeast
Peak: Larvae feed and enlarge bags June–August; bags overwinter with eggs
Kansas City, MO · St. Louis, MO · Oklahoma City, OK
pestView treatment
Moderate
Cankerworm (Inchworm)
Alsophila pometaria / Paleacrita vernata
Eastern and central United States and southern Canada
Peak: Larvae feed and defoliate in spring (April–May) as leaves expand
Charlotte, NC · Richmond, VA · Boston, MA
pestView treatment
Moderate
Cytospora Canker
Cytospora / Leucostoma spp.
Throughout the United States; attacks stressed, drought- or winter-injured trees
Peak: Cankers expand in spring and fall; symptoms most visible in summer dieback
Denver, CO · Salt Lake City, UT · Minneapolis, MN
fungusView treatment
Moderate
Scale Insects
Coccoidea (various species)
Throughout the United States on a wide range of trees and shrubs
Peak: Vulnerable mobile 'crawlers' emerge late spring–summer (species dependent)
Atlanta, GA · Houston, TX · Long Island, NY
pestView treatment
Low2 entries
Diagnose & treat

Every marker traces back to a full diagnostic entry.

Symptoms, range, peak season, severity and treatment options — cross-linked to the tree species each pest attacks. The library is the source this map reads from.