Banded Alder Borer- Rosalia funebris
Just a few weeks ago, a banded alder borer was spotted by a volunteer during a Restoration Work Party held here at SHADOW Lake Nature Preserve! This beetle was found in SHADOW’s Alder Grove.
Although its striking white and black stripes seem like they come from the tropics, the banded alder borer is a Pacific Northwest native. It is commonly mistaken for a lookalike, the Asian longhorn beetle, a destructive and invasive pest that causes severe tree damage by boring wood. Fortunately, banded alder borer beetles feed on dead wood of trees like alder, ash, and other hardwoods. These eating habits expedite the trees’ decomposing process, an integral part of a healthy an ecosystem. For this reason, the native banded alder borer is not a pest but rather a helpful and welcome Pacific Northwest native insect!
Oddly, one of the best places to spot this beetle is around freshly painted houses during hot summer days. Although scientists are not entirely sure what causes this to occur, some believe that the warm paint emits an attracting scent or “pheromone” that draws the beetles in. Because banded alder borers are somewhat uncommon to see, our volunteer was very lucky to spot this beetle in the wild!
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Native Animal of the Month: Banded Alder Borer
Found one on my fence , Wooden fence next to some old oak Stumps.
Found one on a patio deck in Victoria, BC near the water. It had blue on it as well. Just awesome. Work was being done in the building but not painting.
My husband has been splitting alder wood on our property that had been downed about 5 years ago. He has spotted multiples of these beetles. They have landed on him and on the splitter. Truly awesome to see fly in. We’ll make sure to leave some debris for them to enjoy.
Found many in a delivery of Oak Mulch in Northern California. It is a beautiful insect. Took my breath away, but am a tad concerned it may cause damage to the house, or fence? Still in awe of it though! Magestic looking!
Found one at work in Corvallis Oregon
Found one in my backyard on Van. Island today, awesome markings!