Tree Health in Montana
A comprehensive state guide for Montana is coming soon. Below are current tree health alerts tracked for this state.
View all Montana alertsCurrent Threats in Montana
Mountain Pine Beetle
INSECTA native bark beetle responsible for massive die-offs of lodgepole, ponderosa, and whitebark pines across western North America. Climate change has expanded its range northward and to higher elevations. Outbreaks have affected tens of millions of acres.
Ips Bark Beetles
INSECTA genus of bark beetles that attack stressed and weakened pines throughout North America. While they typically colonize dying trees, drought and overcrowding can trigger outbreaks that kill healthy timber.
Dutch Elm Disease
DISEASEA devastating vascular wilt disease spread by elm bark beetles that has killed millions of American elms since the 1930s. The fungus blocks water-conducting vessels, causing rapid wilting. It fundamentally changed the American urban landscape.
Powdery Mildew
FUNGUSA widespread group of fungal diseases that produce a distinctive white powdery coating on leaves and shoots. It affects hundreds of tree, shrub, and plant species. Unlike most fungi, it thrives in warm, dry conditions with high humidity.
Armillaria Root Rot
FUNGUSOne of the most widespread and destructive forest diseases in the world, caused by a complex of honey mushroom species. It attacks stressed trees through root contact and can persist in dead stumps for decades, infecting nearby healthy trees.
Dothistroma Needle Blight
FUNGUSA fungal disease of pines that causes premature needle loss and can significantly reduce growth and vigor. It affects many pine species but is especially damaging to Austrian, ponderosa, and Monterey pines. It has increased in severity with climate change.
Cytospora Canker
FUNGUSA common fungal disease of spruce and other conifers that causes branch dieback, typically starting from the lowest branches and progressing upward. Colorado blue spruce and Norway spruce are especially susceptible. The fungus enters through wounds or stressed tissue. White resin bleeding on bark is a hallmark sign. Stressed trees are most vulnerable.
Bronze Birch Borer
INSECTA native North American wood-boring beetle that attacks birch trees, especially paper birch and European white birch in landscape settings. Larvae feed under the bark in a serpentine pattern, disrupting nutrient and water transport. Dieback starts at the top of the crown and progresses downward, the opposite pattern of many other pests.
Asian Longhorned Beetle Damages hardwood trees by tunneling deep into trunks and branches
INSECTAsian Longhorned Beetle Damages hardwood trees by tunneling deep into trunks and branches - identified by USDA APHIS as a pest threat.
conical brittlestem
FUNGUSconical brittlestem observed in the wild. Research-grade iNaturalist observation.
Asian Lady Beetle
INSECTFound alive but in terrible shape. Was swimming around in the water bowl we put out for feral cats here. Also appeared to have had a run in with a spider web, as it had something stuck all over it. Got a lot of suggestions for fungi and parasitoids that target ladybeetles, so maybe its appearance is more a function of a disease or parasite process taking place. It was definitely having trouble getting adound, but could be due to having been in the water for a long time and/or having bits of web
Police Car Moth
INSECTPolice Car Moth observed in the wild. Research-grade iNaturalist observation.
Black Damsel Bug
INSECTBlack Damsel Bug observed in the wild. Research-grade iNaturalist observation.
Cedar-Apple Rust
FUNGUSA fungal disease requiring two hosts to complete its life cycle: eastern red cedar (juniper) and apple or crabapple trees. It causes economic losses in apple orchards and aesthetic damage to landscape cedars.
Black Witch
INSECTFound trapped inside our screen porch at 10 pm. Took a photo then helped it get outside.
Bronze Ground Beetle
INSECTBronze Ground Beetle observed in the wild. Research-grade iNaturalist observation.
Punctured Tiger Beetle
INSECTPunctured Tiger Beetle observed in the wild. Research-grade iNaturalist observation.
Transverse Lady Beetle
INSECTTransverse Lady Beetle observed in the wild. Research-grade iNaturalist observation.
Thirteen-spotted Lady Beetle
INSECTThirteen-spotted Lady Beetle observed in the wild. Research-grade iNaturalist observation.
Seven-spotted Lady Beetle
INSECTThis is a picture of a Coccinella septempunctata at Fort Armistead Park in Baltimore City, Maryland.