ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 



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Overwintering eggs at the bases of the needles of infested 

 plants produce tiny, light green mites in early spring. Through 

 a series of molts the mites mature into larger, darker green, or 

 almost black individuals, with spinelike hairs that curve back- 



Fig 44— Spirea aphid: infestation of this green plant louse on a spirea 

 shoot. After sucking sap from the shoots of spirea for a short time in 

 spring, this aphid develops a Avinged form that migrates to other host 

 plants. 



ward over their robust bodies. The mites can be seen as moving 

 specks on a white piece of paper or dish that has been held under 

 infested branches struck sharply with the hand. This species 

 has a number of generations in a season. 



Control Measure 9 (end of circular) as soon as mites are de- 

 tected, usually in April or May. 



