Oregon

288 active alerts in this region

TreeIssues monitors plant and tree health threats across Oregon. Below you will find current alerts for pests, diseases, fungi, and invasive species that have been detected in the state. Alerts are sourced from USDA, USFS, and Oregon state agricultural agencies. Each alert includes severity ratings, affected species, symptoms, and recommended treatments.

Mountain Pine Beetle

CRITICAL

Insect

A 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.

Affecting 9 regions

Dutch Elm Disease

CRITICAL

Disease

A 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.

Affecting 45 regions

Fire Blight

HIGH

Disease

A bacterial disease that primarily affects members of the rose family, including apple and pear trees. It can destroy entire orchards in a single season. Bacteria spread rapidly during warm, wet spring weather through blossoms and wounds.

Affecting 32 regions

Thousand Cankers Disease

HIGH

Disease

A disease complex involving the walnut twig beetle and an associated fungus that has caused significant mortality of black walnut, particularly in western states. Thousands of small cankers coalesce to girdle branches and the trunk.

Affecting 15 regions

Armillaria Root Rot

HIGH

Fungus

One 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.

Affecting 36 regions

Verticillium Wilt

HIGH

Fungus

A soilborne fungal disease that affects hundreds of plant species including maples, elms, redbuds, and many other trees. The fungus invades through roots and colonizes the vascular system, blocking water transport. Symptoms often appear suddenly on individual branches. Maples are particularly susceptible. Olive-green to brown streaking in the sapwood is diagnostic.

Affecting 27 regions

Phytophthora Root Rot

HIGH

Fungus

A group of water-mold diseases that attack the roots and root collar of many tree species. Phytophthora thrives in wet, poorly drained soils. It destroys fine roots and can girdle the trunk at the soil line. Affected trees show a general decline that is often misdiagnosed as drought stress. Oaks, dogwoods, rhododendrons, and many other species are susceptible.

Affecting 31 regions

Bronze Birch Borer

HIGH

Insect

A 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.

Affecting 26 regions

Oregon

Mountain Pine Beetle

Dutch Elm Disease

Fire Blight

Thousand Cankers Disease

Armillaria Root Rot

Verticillium Wilt

Phytophthora Root Rot

Bronze Birch Borer

Ips Bark Beetles

Sudden Oak Death

Anthracnose

Apple Scab

Dothistroma Needle Blight

Seven-spotted Lady Beetle

Eye-spotted Lady Beetle

Painted Lady Beetle

Echo Azure

California Tortoiseshell

Painted Lady

Feralia februalis

Western Boxelder Bug

Blue-green Sharpshooter

Lichen Agaric

Asian Longhorned Beetle Damages hardwood trees by tunneling deep into trunks and branches

Asian Lady Beetle

Convergent Lady Beetle

Western Polished Lady Beetle

Casey's Lady Beetle

Gray Hairstreak

Western Tiger Swallowtail

Cinnabar moth

Pale Swallowtail

Isabella Tiger Moth

Clodius Parnassian

Two-spotted Grass Bug

Sawadaea bicornis

Rockweed

Red Admiral

Hedge Nettle Stink Bug

Wrinkled Cortinarius

Psychedelic Ovoid Mushroom

Brown-eyed Wolf Lichen

Feather Boa Kelp

Japanese Wireweed

Flame-shouldered Dart

Rhododendron Leafhopper

Short-stemmed Russula

Peony Red Spot

club-like tuning fork

alpine jelly cone

Common Red Soldier Beetle

Campyloneura virgula

Loxosporopsis corallifera

Margined Burying Beetle

Sulphur Moth

Spotted Tussock Moth

Simple Wave

Barberry Geometer Moth

Pale Glyph

North American Common Water Strider

Meadow Spittlebug

Northern Red Belt

woolly bird's nest fungus

pale oyster

The Prince

Little Rockweed

Sea Palm

studded sea balloon

Sea Cauliflower

seersucker kelp

winged kelp

Southern stiff-stiped kelp

sea cabbage kelp

Ornate Checkered Beetle

Guenée's Carpet Moth

Flat Pompom Kelp

Desmarestia herbacea

dense-clumped kelp

Banded Alder Borer