Populations of this defoliating caterpillar surged in 2014

in Colorado Springs.  You can see groups of partially or totally defoliated trees in many areas.  Especially noticeable were Spruce trees with a distinctive orange colorations along the Academy Blvd. corridor and a

large area of Gray Fir trees on Cheyenne Mountain below NORAD.  Blue Spruce, Douglas Fir and White Fir trees are hosts to this insect.These caterpillars feed on new needles, partially eating them and causing the remaining portion of the needles to turn an orangish-brown.  Eventually larvae move to feed on older needles, stripping the branches.  After the initial season of feeding, a tree can usually put out new growth the following year, but with repeated defoliation a tree will die.

It is important to spray for this insect. Chemical
controls should be applied shortly after egg hatch in late May or early June.  A biological option; Bacillus thuringiensis, is also available.  It is a bacterium that feeds on caterpillars. Timing is critical and it is not as effective.

Tussock moth overwinters in the egg stage near the female’s pupal case.  Eggs hatch in late May and larvae move to feed on new growth, often in the top of the tree. They feed heavily from June into July, growing into large caterpillae, distinguished by tufts of hair. They pupate by August and the nondescript adult moths mate and then lay eggs.  Many of you will see a new recommendation for this on your annual proposal!If you would like your trees checked, please call our Colorado Springs office at 719.444.8800 for a free evaluation.