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Host: Ponderosa pine
 Symptoms/Signs:
Insect appearance varies between species. R. bushnelli
adults have a wingspread of 10 to 15 mm; forewings are mottled yellowish
gray and reddish brown. Larvae are yellowish with black heads, and
about 9 to 12 mm long when mature. R. neomexicana adults
have a wingspan of about 0.24 mm. Forewings are irregularly banded
with transverse bars of dark gray, blackish and brick-red scales
on the inner two-thirds of the wing. Larvae are usually orange in
color with dark brown to light tan head capsules and are about 12
to 16 mm long when fully developed.
 Biology:
Larvae mine inside new shoots in spring and early summer,
killing them. Both lateral and terminal shoots are attacked. Larvae
initially mine needles and then bore into the shoot. Pitch tents,
frass, and silk webbing are all signs of tip moth activity. Once
in the shoots, larvae feed between the pith and the bark, eventually
hollowing out the shoot.
Effects: Larvae mine in the phloem and xylem
of lateral and sometimes terminal shoots. Small trees, less than
2 m are most susceptible. Shoots are killed by the attacks. Repeated
attacks slow growth and cause crooks, forks, multiple stems, and
spike tops. Tip moths rarely kill established trees outright, but
attacks can affect survival of young planted seedlings.
Similar Insects and Diseases: See western
pineshoot borer.
References: 23,
43
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