Pine and Spruce Insects

Spruce Bud Scale

Spruce bud scale (Physokermes piceae) attacks mainly Norway spruce but it will attack other spruces. This scale is small and is often clustered in-groups of 3 to 8 at the base of new shoots. Their size and color often allows them to be over looked or mistaken as buds. They are round and reddish-brown in color. Lower branches are more often attacked than higher branches. Severe infestations can produce sufficient honeydew to develop so that sooty mold will grow. In addition severe infestations can cause lower branches to die especially on trees that are already weak or stressed. There is only one generation per growing season. The immatures over-winter on the under side of the needles. In the spring the females move onto the twigs to complete their development. Crawlers usually appear in June.

Check with your local land grant university (Cooperative) Extension Service for recommended insecticide. Apply when hills-of-snow hydrangea is in bloom. Summer oils will turn blue spruces green.

Written by James Schuster, Extension Educator, Horticulture, and reviewed by Dr. Phil Nixon Extension State Specialist, Entomology, University of Illinois at Urbana-Champaign.