Origin:
There are many native species in North America, along with the imported European Pine Shoot Moth.
Biology:
At least 2 dozen species of these native moths occur in North America, along with at least one species native to Europe, Rhyacionia buoliana – the European Pine Shoot Moth. This species is reported from southwestern Canada, the Pacific Northwest, Utah, and most of the northeastern U.S. It occurs throughout Europe as well as into South America. The larvae bore into the new shoots of pines and fir trees, causing the death of that shoot. They also may feed within older tissues and cause distortion and twisting of the ends of the stems. They do not kill trees, but do cause disfigurement and abnormal growth, including the growth of many new stems. The larva spins a bit of silk around the base of the needles and burrows in to feed inside, eventually pupating within the shoot. There is a single generation each year with the late stage larva overwintering.
Identification:
Adult moths have a wingspan of about ¾ inch, depending on the species. The forewings are a mixture of rusty red or orange and gray patches, with occasional silvery markings. The forewings are long and have the outer end curved.
Characteristicts Important to Control:
Pruning of infested tips of pines that are small and in sparse plantings will be helpful, but not useful for tall trees or dense forests. The release of parasitic wasps has so far been unsuccessful in North America for the damaging European species. Insecticide applications timed to the emergence of adult moths may help to kill first instar larvae before they are able to enter the shoots.
