Frank A. Hale, Jamie Yanes Jr., and Harry E. Williams, University of Tennessee

Taxonomy

Domain	Eukarya
Kingdom	Animalia
Phylum	Arthropoda
Subphylum	Hexapoda
Class	Insecta
Subclass	Pterygota
Infraclass	Neoptera
Superorder	Paraneoptera
Order	Hemiptera
Suborder	Sternorrhyncha
Infraorder	Aphidomorpha
Superfamily	Aphidoidea
Family	Aphididae
Subfamily	Lachninae
Tribe	Eulachnini
Genus	Cinara

Scientific Name

Cinara strobi

Common Name

white pine aphid

Introduction

The white pine aphid Cinara strobi (Fitch) occurs wherever Eastern White Pines are grown. This pest uses its needle-like mouthparts to suck sap from twigs and branches. Severely infested parts of trees turn yellow and drop their needles. White pine aphid adults are large (6 mm long), long-legged, and spider-like in appearance. The body is shiny dark brown with a white stripe down the middle of the back. White powdery spots on the sides are often present. During the fall, winged females lay blackish eggs, end-to-end, in a row of eight or more on the needles. This aphid usually overwinters in the egg stage; however, if the weather is mild, some individuals from the last generation survive through the winter. Eggs hatch in the spring and resulting wingless females produce living young. As the season progresses, several over lap ping generations may occur. By late summer, large populations may be present. Droughty weather at this time will increase needle drop. Each new generation moves to fresh sites on the tree to feed. Adults of the last generation of the summer produce overwintering eggs in the fall. Heavy infestations of aphids may kill young trees or may cause reduced growth. As the aphid feeds, it excretes honeydew. This sticky sub stance is the excrement from the aphid. A black sooty mold is commonly found growing on the honeydew. Sooty mold reduces the quality of trees and may reduce the amount of sunlight available to the leaves. Ants may also be found feeding on the honeydew. These ants feed on honey dew and protect aphids by discouraging the natural enemies of the aphids. This protection aids in the buildup of aphid populations.

Control Measures

White pine aphid infestations may be prevented by treating trees with dormant oil before growth starts in the spring. Do not use oil until the temperature stays above 4°C for 24 hours. Control of spring and summer infestations can be achieved through chemical controls. Please consult your state extension service for the appropriate produce recommendation. Treat individually infested trees when more than 30 percent of the shoots have aphid colonies.