Monday, August 3, 2009

A new chapter in the quaking aspen and longhorn beetle story

The longhorn beetles aka aspen or poplar borers (Saperda calcarata) have hatched and lots of animals are after the larvae before they burrow deep into the quaking aspen (Populus tremuloides). This is just another chapter in the fascination ecology of quaking aspen and longhorn beetles. In order to determine how long it takes for the eggs to hatch, I labeled the places where female aspen borers laid their eggs (click here for more information), and I have been periodically checking back in on the egg masses (yes, this is the kind of thing I wonder about).

It turns out, it takes about 2.5 weeks for the larvae to hatch (which is consistent with the literature). I first noticed they hatched when I saw ants congregating around the egg mass locations, pulling the newly hatched larvae out (see photo below).All this activity on the aspen did not go unnoticed. Soon, bald-faced hornets moved in, displacing the ants, feeding on the larvae. And, if you recall, this is where the whole story began, with bald faced hornets chewing bark to mix saliva to make their nests.

It did not take long before any of the surviving larvae burrowed deeper into the cambium, protected from ants or bald-faced hornets. However, still shallow in the trunk or branches of the aspen, they are easy prey for woodpeckers. Last night a hairy woodpecker showed up. You can see in the photo at the beginning of the post and below this male hairy quickly drilled a hole into the aspen and spent the evening eating the borer larvae.


  1. David,

    Thanks for such an interesting post. We have a Bald-faced Hornet nest on the probe portion of our satellite dish right over our walkway.

  2. But anyway these beetles are a necessary element of the nature