Southwestern Pine Tip Moth
The larval stage of this pest most often damages Austrian, mugo, scots and ponderosa pines.
Tips of pine trees are brown and curled. Upon closer inspection, small holes can be visible at branch tips. Enlarge below image for better view of damage.
Moth adults emerge in midspring after spending the winter as pupae at the base of tree trunks. Eggs are laid on the twig terminals during the “candling stage” of pine tree shoots. Larvae hatch out of the eggs and tunnel into needles and feed. Larvae drop to the ground around August-September and pupate. There is only 1 generation per year.
Young larvae do minimal damage as they just feed on individual needles. As they mature, they move into the shoots and feed inside. This causes the shoots to “crook.” After multiple generations of infestation, tree growth is stunted.
In most instances, natural enemies knock the population of southwestern pine tip moth back in check. However, there are insecticide applications available to kill larvae if necessary. Timely pyrethroid sprays or systemic acephate have shown to be effective treatments.
For more information on pine tip moths, see Colorado State University extension bulletin 5.529: http://www.ext.colostate.edu/pubs/insect/05529.html