Chrysomelid beetle larvae chew on willow leaves – leaving these patterns of skeletonization behind. Photo by Carri LeRoy 

Willows across the Pumice Plain of Mount St. Helens provide more than just riparian vegetation! They provide shelter, habitat and food to a variety of insects. Insects like Chrysomelid beetle larvae chew their way through willow leaves!

The poplar & willow stem-boring weevil, Cryptorhynchus lapathi, was introduced to Mount St. Helens in 1989. Photo by Carri LeRoy 

Another insect that utilizes the willows is the stem-boring weevil, which is native to Europe but was introduced to Mount St Helens in 1989! The tiny long-nosed guys, show up a lot in our studies as they cause branch death and mortality of willows.    

Galling herbivores like this likely galling midge show variation in activity across the Pumice Plain of Mount St. Helens. Photo by Carri LeRoy

Insects like galling midges have specialized feeding behaviors that require willow leaves as a host. They create new microhabitats for their young via galling. Stay tuned to learn more about the aquatic macroinvertebrates that colonize willow leaves that fall into streams!