Cerambycidae

Saperda

Populus fremontii

Arizona

California

Idaho

Nevada

New Mexico

Texas

Utah

Populus nigra

Alabama

Arkansas

Colorado

Connecticut

Delaware

Florida

Georgia

Illinois

Indiana

Iowa

Kansas

Kentucky

Louisiana

Maine

Maryland

Massachusetts

Michigan

Minnesota

Mississippi

Missouri

Nebraska

New Hampshire

New Jersey

New York

North Carolina

North Dakota

Ohio

Oklahoma

Oregon

Pennsylvania

Rhode Island

South Carolina

South Dakota

Tennessee

Vermont

Virginia

Washington

West Virginia

Wisconsin

Wyoming

Populus spp

Populus tremula

Alberta

British Columbia

Ontario

Saskatchewan

Populus trichocarpa

Populus tristis

Alaska

Montana

Salix spp

Saperda populnea

Saperda populnea

Oval twig gall, length 1.5 to 2 inches, beetle

Plant Galls and Gall Makers

Saperda populnea

Long-horned beetles, (Saperda populnea L. or a closely related species) cause spherical or spindle-shaped stem galls (2 cm in diameter) on black cottonwood and on willows. Infestations are often heavy; the shape of the tree may be somewhat disfigured as a result. Adult females lay eggs in late spring in holes that they chew in the bark. When the egg hatches, the larva mines the cambium and then turns into the wood where it excavates a gall chamber. Growth from the wounded cambium causes the swelling. One or two adults emerge from each gall after one to two years of larval development. The adults feed on poplar leaves.

Common insect and mite galls of the Pacific Northwest

Saperda populnea
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Hosts: cottonwoods and willows

Galls of this beetle are recognized by the hemispherical cuts (scars) made by adult beetles into which eggs are inserted between the phloem and xylem tissues. 

Plant Galls of the Western United States

HOST PLANTS
Salicaceae, oligophagous

Populus nigra, tremula, trichocarpa; Salix alba, aurita, caprea, x fragilis, apponum. 



Plant Parasites of Europe