Figure 192. Lophodermella arcuata causes browning of 1-year needles, which is most noticeable just before bud break of current year needles.
Symptoms/signs: This fungus is identified by the dark brown to concolorous,
elongate to elliptical, fruiting structures, which develop on previous
year’s dead and dying needles.
Biology: Fruiting bodies in dead, second
year needles open by means of a longitudinal fissure during warm
wet weather and release colorless spores that have sticky, gelatinous
sheaths. Airborne spores settle and penetrate young, developing
needles. The following spring, diseased needles turn reddish brown
and by July, they are straw colored.
Figure 193. Fruiting bodies of Lophodermella arcuata are the same color as the faded needle.
Effects:Lophodermella arcuata infects only the current year’s
needles, and a single attack results in only partial defoliation
of the host. Repeated consecutive infections are rare, but can lead
to reduced tree growth and vigor.
Similar Insects and Diseases: This is the
only known needle cast disease of white pine in the Southwest.