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Host: Ponderosa pine
Symptoms/Signs:
Lophodermella cerina infects the needles of seedlings,
saplings, and the lower crown of larger trees. Current year needles
are infected and turn brown and die by early summer of the following
year. Following bud break, green current year needles and brown
previous year needles give the tree a distinctive appearance. The
brown needles are “cast” prematurely compared to normal
needle drop. Successive years of infection occur only with favorable
weather conditions and results in thin crowned trees.
Biology: Fruiting bodies are short, oval,
light brown, and easily overlooked. The spores mature after the
needles have been cast. They infect new needles shortly after bud
break. Spores germinate and infect needles directly through the
epidermis. Infected needles extend normally and are usually killed
by the fungus before the next year’s needles emerge.
Effects:
Although rare, growth loss is the primary long-term effect
of needle cast. Successive years of infection are usually the result
of repeated abnormally high rainfall in spring and early summer.
Though trees can be killed if infection is repeated for several
years in a row, they are more often predisposed to other pests.
Similar Insects and Diseases: From a distance,
trees with needle cast symptoms may be mistaken for those affected
by winter damage, salt
damage, or needle miners.
On close inspection, needle cast needles are completely brown with
dark fruiting bodies present. Winter damage, salt damage, and needle
miner needles often have brown needle tips with green bases.
References: 71,
82, 92
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