Hosts

In Alaska, spruce aphid infests spruce species, especially Sitka spruce. Neither tree size nor age influences whether a tree will be infested with spruce aphids; however, tree location is important. In Alaska, spruce in coastal areas and trees stressed by urban and landscape situations are particularly susceptible to damage caused by spruce aphid. Spruce aphids can be found at higher elevations in Alaska if other environmental factors are favorable.

Known distribution

Spruce aphids have been present in Southeast Alaska for decades. A few notable populations have also been detected throughout the years along Prince William Sound, the south side of the Kenai Peninsula, and the Kodiak Archipelago. In 2015, spruce aphids and spruce aphid damage were detected on the south side of Kachemak Bay and in Homer, representing the first record of these aphids on the western side of the Kenai Peninsula. In 2016, damage continued in these areas and was also noted on several islands of the Kodiak Archipelago.

map of Homer Kenai area infested sample areas that increase over time — During surveys conducted between spring and fall of 2016, sites with spruce-aphid infested trees were mapped. Not all locations were surveyed during each trip. (Dubois, G. and S. Swenson. 2016. Homer Spruce Aphid Monitoring and Expantion. Trip Report filed October 17, 2016. R10-S&PF-FHP-2016.)

map of Southeast and Southcentral Alaska with colored dots — This map shows areas of spruce aphid damage statewide that were mapped between 1981 and 2015. Recent activity is designated by year. Southeast Alaska has seen several spruce aphid outbreaks at various locations in the decades since the pest was first established there.