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.
66 hotspots across 22 pests & diseases · 53 live alerts
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 Oct 17, 2026.
53 recent developments
USDA APHIS expanded the ALB quarantine in Charleston County, adding 16.5 sq miles in Mount Pleasant and 25.2 sq miles in Hollywood, effective September 4, 2026, following confirmed infested trees found in both areas.
New York agriculture officials confirmed box tree moth in Nassau County on Long Island in mid-September 2026, the first detection outside the state's existing 34-county upstate quarantine. Additional surveys and coordinated trapping with USDA APHIS were initiated.
Washington State Department of Agriculture and USDA APHIS confirmed the first emerald ash borer detection in Walla Walla County near College Place, with larvae and D-shaped exit holes found in ash trees. USDA confirmed specimens on October 14, 2026.
NC Cooperative Extension reported established spotted lanternfly infestations in Forsyth, Davidson, and Guilford counties, with additional sightings in Rockingham, Caswell, Rowan, Mecklenburg, and Caldwell counties as of October 2026.
Local reporting described an exponential increase in spotted lanternfly populations in parts of Greater Columbus this summer. The pest has spread widely through Franklin County, which is under Ohio's statewide quarantine.
Michigan officials confirmed a spotted lanternfly population near Niles in Berrien County, the first confirmed population in southwest Michigan, identified through monitoring by a regional invasive species management cooperative.
Minnesota Department of Agriculture confirmed emerald ash borer in Lincoln and Pipestone counties on Sept 21, 2026, with emergency quarantines restricting firewood and ash material movement from both counties.
UMass Amherst reported continuing southern pine beetle outbreaks on Martha's Vineyard, Nantucket, and Cape Cod, affecting pitch pine. Outbreaks began in 2023 and monitoring continued through the 2026 season.
New York State confirmed box tree moth in Nassau County in mid-September 2026, marking the first Long Island detection and first find outside the existing 34-county quarantine area.
MDARD confirmed a spotted lanternfly population in Berrien County, a major grape-producing region, and a newly confirmed population in Washtenaw County as of September 10, 2026. Confirmed counties now include Berrien, Jackson, Lenawee, Macomb, Monroe, Oakland, Washtenaw and Wayne.
Texas A&M Forest Service confirmed emerald ash borer in Delta, Erath, Hardin, Walker, and Wood counties by September 5, 2026, representing continued spread identified through the state's 2026 purple-trap monitoring program.
Emerald ash borer was found in an ash tree near Minnesota Avenue and 4th Street in Hayward, making it the seventh municipality in Sawyer County with a confirmed infestation.
EAB was found in Bismarck in late August 2026 during ash tree removals, the first detection in central North Dakota. Burleigh County is now under quarantine restricting movement of hardwood firewood and ash material.
Box tree moth was first confirmed in New Jersey on June 10, 2026 in Cape May County and later in Cumberland County. By Aug 27, 2026 a quarantine covering Cape May, Cumberland, and Atlantic counties was in place, with all life stages active in southern New Jersey.
About 8,000 parasitoid wasps were released at Ki-Chi-Saga Park in Chisago County on August 26, 2026 as biological control against EAB. Emerald ash borer is now confirmed in 60 Minnesota counties.
Maryland expanded its box tree moth quarantine effective Aug 24, 2026 to Caroline, Cecil, Kent, and Queen Anne's counties, bringing the total to eight Maryland counties under quarantine after confirmed infestations.
Oklahoma Forestry Services reported emerald ash borer in Atoka County, adding to infestations in seven other Oklahoma counties. Officials issued warnings and published an updated EAB map on August 23, 2026.
Rhode Island DEM reported on August 20, 2026 that spotted lanternfly is established statewide, with over 1,000 reports in July and over 1,500 in August, indicating rapidly increasing populations across the state.
Washington state confirmed emerald ash borer in Vancouver after a specimen was identified in early August 2026. A statewide firewood quarantine was initiated the week of August 19 to contain the outbreak.
Texas A&M Forest Service confirmed emerald ash borer in Delta, Erath, Hardin, Walker, and Wood counties on August 20, 2026, bringing new-county detections in Texas to eight for 2026.
Nebraska's July 2026 forest health report, released August 12, confirmed emerald ash borer in 20 counties, with new counties being added each year as the pest spreads through urban and rural tree populations.
New Jersey Department of Agriculture reported renewed summer spotted lanternfly infestations across parts of New Jersey as of August 12, 2026. Adults are feeding on sap from over 70 plant species and laying egg masses that fuel recurring outbreaks.
Maine DACF reported in an August 11, 2026 bulletin that EAB was found in Bristol, Lincoln County marking the first detection there, and in Jackman, Somerset County, well outside the existing quarantine area. The state indicated the quarantine will be expanded.
By late July 2026, spotted lanternfly infestations in Hampshire County, Massachusetts grew from 3 communities in August 2025 to 10 cities and towns, with confirmed spread into Sunderland in Franklin County.
Larvae found in a dying ash tree in northeast Colorado Springs were confirmed as EAB on Aug 6, 2026, marking the first detection south of Parker and Highlands Ranch in Colorado.
Allegheny County recorded 104 citizen spotted lanternfly reports from January through June 2026, the highest of any Pennsylvania county. The pest is now confirmed in 56 of Pennsylvania's 67 counties.
USDA APHIS confirmed box tree moth at private residences in Cape May County, New Jersey, prompting a local quarantine order with movement restrictions on boxwood plants.
As of July 28, 2026, confirmed spotted lanternfly infestations were reported across Columbia, Dutchess, Greene, Orange, Putnam, Rockland, Sullivan, Ulster, and Westchester Counties in New York's Hudson Valley.
Detection traps at more than a dozen sites in Portland during summer 2026 showed no further spread of emerald ash borer beyond the area first confirmed in summer 2025; the city lifted its ash-tree pruning moratorium September 30, 2026.
Beech leaf disease was confirmed in more than 200 American beech trees at Saddler's Woods in Camden County. The New Jersey DEP confirmed the disease is now present in all 21 New Jersey counties.
USDA APHIS expanded Maryland's federal box tree moth quarantine to four Eastern Shore counties following confirmations in Caroline and Cecil counties on July 24 and Queen Anne's County on August 7, 2026. The quarantine restricts interstate movement of boxwood plants and plant material.
A Colorado report from October 4, 2026, described widespread ponderosa pine mortality linked to mountain pine beetles, with active responses including pheromone packets, insecticide injections, and removal of infested trees.
Wisconsin's Plant Disease Diagnostics Clinic identified oak wilt in a black oak sample from Eau Claire County during the September 26 to October 2 reporting period. No outbreak size or control program was described.
Maryland Department of Agriculture and USDA APHIS expanded the box tree moth quarantine into Harford County effective September 24, 2026, bringing the state total to nine quarantined counties. The expansion followed confirmation of the pest in Kent County.
Michigan confirmed box tree moth in Genesee County via USDA trapping near the quarantine perimeter, making it the 14th Michigan county under quarantine. Movement of regulated boxwood material out of the area is now restricted.
Penn State Extension reported in September 2026 that beech leaf disease caused by the nematode Litylenchus crenatae mccannii was affecting areas across Pennsylvania, with trunk injections, soil treatments, and foliar sprays in use.
Luzerne, Lackawanna, Wyoming, Bradford, Sullivan, and Venango counties remain under spotted lanternfly quarantine. As of September 4, 2026, Pennsylvania had not added any new counties to the quarantine list in 2026.
UMass Amherst reported Asian longhorned beetle remains a concern in Worcester, Shrewsbury, Boylston, West Boylston, and parts of Auburn, associated with the longstanding Worcester County quarantine area.
UMass Extension reported a significant outbreak of giant tar spot caused by Rhytisma acerinum on Norway maple in Massachusetts, with the disease causing premature leaf shedding especially in shaded trees. The report was published September 3, 2026.
UMass Extension documented Verticillium wilt on American elm in Massachusetts, confirmed by lab culture of symptomatic branches as of September 3, 2026. The report warns Verticillium can kill American elms, especially when combined with drought stress.
Ohio Department of Agriculture and USDA released roughly 4,000 acres in Tate Township, Clermont County from the ALB quarantine on August 23, 2026. About 37.8 square miles in the county remain under quarantine.
Ohio extended a statewide spotted lanternfly quarantine in February 2026, restricting movement of trees and nursery stock. Franklin County has been under quarantine since 2023 and continues to report active infestations.
Michigan Invasive Species Program and USDA APHIS issued a statewide alert on August 10, 2026 urging residents to check trees for Asian longhorned beetle signs including round exit holes and bark scars. August is designated Tree Check Month for heightened surveillance.
Minnesota DNR reported on August 10, 2026 that forest tent caterpillars damaged about 60,000 acres of trees in Aitkin County and surrounding counties, up from 41,200 acres in 2025. A larger outbreak in 2027 is being monitored.
Spruce budworm caused severe defoliation in northeastern Oneida County and southeastern Vilas County as of Aug 5, 2026, with budworms expanding onto hemlock and tamarack near Sugar Camp, Oneida County.
Effective August 4, 2026, USDA APHIS added Ashtabula, Clark, Cuyahoga, Lake, Lorain, Lucas, and Preble Counties, Ohio to the federal box tree moth quarantined area following confirmed detections in 2025.
USDA APHIS removed 7.4 square miles from the Asian longhorned beetle quarantine in Nassau and Suffolk Counties, New York on July 30, 2026, following completed host-tree surveys and eradication activities. Portions of the quarantine in both counties remain in effect and eradication continues.
The Wisconsin Plant Disease Diagnostics Clinic reported Cytospora canker in juniper from Dane County during the October 10-16 reporting period. The report is a routine diagnostic finding with no regional outbreak characterization.
The Wisconsin Plant Disease Diagnostics Clinic reported Verticillium wilt in aralia and Japanese maple samples from Walworth and Dane counties during the October 10-16 reporting period. The reports are routine diagnostic findings with no regional outbreak characterization.
Pennsylvania DCNR reported spongy moth populations declined in 2026 after a 2021-2026 outbreak; aerial suppression treated 3,160 acres in 2026, down from an average of 155,072 acres annually during the outbreak period.
USDA APHIS removed the Town of Shrewsbury (21.8 sq mi) in Worcester County from the Asian longhorned beetle quarantine after completing final host-tree surveys. Nearby areas of Worcester County remain under quarantine.
USDA APHIS removed 6.2 square miles in southeastern Tate Township from the Asian longhorned beetle quarantined area after final surveys of host trees. The remainder of Tate Township remains under quarantine.
Wisconsin forestry officials reported in early August 2026 that aspen leaf beetles were causing light to moderate defoliation of young quaking aspens in Vilas and Oneida counties, with scattered young white pines also experiencing significant defoliation.
14 high-priority threats tracked
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.