Pine Tip Moth
May 14th, 2019
Austrian, Bristlecone, Mugo, Pinyon, Ponderosa, and Scotch pines.
This insect attacks only the new growth at the ends of the branches. The affected shoot turns brown, shrivels, and may crook over. The damaged shoot is hollow and is easily broken off.
Eggs are laid on the buds of new shoots in April and hatch about the time that shoots emerge from the buds into a smooth, ½” long, yellowish-orange caterpillar. The caterpillar bores into the shoot and hollows it out. In August it spins a cocoon, overwinters until spring, and emerges as a reddish-brown moth to lay eggs.
Pine Tip Moth damage is not very harmful to the tree but is visually displeasing. Preventively spraying when needles have elongated to ½ – ¾” gives 75% to 95% control. Timing is very exact and some trees experience needle elongation sooner than other trees depending on location, weather, etc. If it is important for a tree to maintain a good appearance a preventative treatment is necessary every year.