Light yellow spots on the needles, later on broad, light to white-yellow cross bands, then large parts of the needles yellow; finally the whole needle reddish brown to violet; needle cast, the current year's needles remaining unattacked; green aphids with red eyes; sooty moulds on the needles.
Affected tree species
Common on various species of spruce; possibilities of errors: mainly early stage of the spruce needle rust Chrysomyxa abietis; especially young trees may be weakened severly and may decline by secondary damaging agents.
Curative measures Insecticides controlling aphids(see official register of Plant Protection)before the time of flushing or during the activity of the aphids in spring.
Sitka spruce aphid damage on Picea pungens, massive browning of needles
Sitka spruce aphid damage on Picea pungens, loss of needles, spreading upwards on the tree
Sitka spruce aphid: green body and red eyes
Yellowing of needles caused by Sitka spruce aphids