Sequoia Pitch Moth

Posted by Randy - November 3rd, 2013

Pitch Moth Damage

Broken top and limbs from Pitch Moth damage

Pitch Moth Adult

Pitch Moth Adult

Pitch Moth Larva

Pitch Moth Larva

The Sequoia Pitch Moth is a small clearwing moth that resembles a bee, and lives only a few days as an adult before laying eggs in bark cracks or pruning cuts. The eggs hatch into a grub larvae which chews its way under the bark. The larvae typically live 2 years in the tree before pupating and emerging as adult moths during May-Sept. The tree reacts to the larval invasion by exuding a heavy flow of resin, or sap, which appears as pink-tan globs on the tree’s bark, often around branch junctions or pruning cuts. In our area the moths attack mainly Pines, especially Austrian, Scots, Mugo, and Ponderosa Pines, but will also infest Spruces and Firs.

The Sequoia Pitch moth has, until recently, been described as a ‘cosmetic nuisance’, but it is a real pest that has become a problem in our region. The larvae chew their way around branch junctions, causing girdling injuries and limb dieback, with broken branches and tops, sometimes leading to whole tree removal. The problem is often worsened by monoculture planting, with Pines in long rows for privacy; typically all the trees will be infested with Pitch Moths.

There is no spray or systemic insecticide control that has been found to work on the Sequoia Pitch Moth. On smaller trees it is feasible to manually remove the larvae by carefully digging them out with a knife or screwdriver. Many of the sap globs are found to be old and empty- sometimes with brown pupal casings where the adult moths have emerged. But live grubs will usually be found in some of the fresher sap globs.

There are commercially available pheromone traps that can be hung on your property to attract and kill adult males, but the traps need to be maintained because they fill up rapidly with moths. Kile Tree Service has had some success in improving tree health and structural integrity using a combination of manual larva removal and pheromone traps- please call for a free consultation and estimate.

More info on the Sequoia Pitch Moth can be found here:

UC Davis

 

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