Assessing mortality and regeneration of larch (Larix laricina) after a 1999-2004 landscape level outbreak of the larch sawfly (Pristiphora erichsonii) in Alaska (Project WC-EM-08-03)

Larch sawfly (LSF) (Pristiphora erichsonii) is an invasive defoliator in Alaska. Based on aerial survey data, this insect has impacted an estimated 600,000 to 700,000 acres of eastern larch (Larix laricina) stands in Alaska during a 6-year period between 1999 and 2004. Mortality of larch within the sawfly-defoliated area was 80 percent or more (aerial survey data) in the majority of affected larch stands. Consecutive years of larch defoliation on the poorest sites resulted in 100 percent mortality.