The Carpenterworm

    What will this larva become?  
    A moth. These pests are attracted to a wide range of hardwood tree hosts such as oak, elm, ash and poplar. In Colorado, we have a lot of ash and poplar according to our CSU entomologist Whitney Cranshaw.  People want trees that are fast growing. They want protection from the wind. 

    Their lifecycle ranges between 3 to 4 years. Carpenterworms form a central cavity with side tunnels inside the tree. These can extend into the sapwood and eventually the heartwood. They emerge in spring about the month of May. You will notice exit holes along the bark. Early signs of detection are small damp spots on the bark.

    Carpenterworms are widespread throughout the US and Canada. The best way to manage these borers will be to hang pheromone traps on the species of trees listed above. Then you know they are present and can coincide your spraying with their egg laying and adult activity. Trunk sprays are recommended. 

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