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Life History 



Wingless, egg-laying females and wingless males are produced 

 during late September and October. After mating, overwintering 

 eggs are deposited by the females. The shiny, oval, black eggs are 

 indistinguishable from those of the rosy and grain aphids. They 

 are most abundant on water sprouts and the vigorous growth termin- 

 als of both old and young trees. Soon after the fruit buds start 

 to show green in the spring, the eggs begin to hatch, which is ear- 

 lier than for the rosy aphid but later than for the grain aphid. 

 Hatching is complete in 7-10 days and the young nymphs begin to 

 suck sap from the new growth of leaves, stems and flower parts. 

 The first generation nymphs develop into stem mothers in 2 to 3 

 weeks, about pink or slightly earlier. The stem mothers are a uni- 

 form pale green easily distinguished from the darker banded yellow- 

 ish-green grain aphids and the rosy aphids. 



Shortly before bloom the stem mothers, without mating, begin 

 to produce living young. Walking about and eating simultaneously 

 while giving birth to their young, they are small prolific aphid 

 factories. Production of living young continues for a month or 

 longer at the rate of 1 to 3 (maximum 10) nymphs per day. The 

 majority of these second generation nymphs develop wings and mi- 

 grate to other parts of the tree or new trees and there again pro- 

 duce living young--the beginnings of new colonies. 



About half of the next generation and some of the later gener- 

 ations may develop wings, and these forms give birth to living 

 young, all of which are females. The wingless forms 

 on the tree continue to produce living female nymphs 

 increase the number of aphids on the original colony 

 are produced only in the fall. 



which remain 

 which greatly 

 si te . Males 



In a single season, 10 to 17 generations may develop depending 

 on weather conditions. All generations may occur on apple trees, 

 whereas the apple grain aphid and rosy aphids spend much of their 

 time away from apples on alternate hosts. 



Control 



Spri ng 



Insurance programs carried out in the early part of the grow- 

 ing season will prevent aphid buildup until late June or early July 

 The severity of rei nfes ta ti on will then depend upon the nearness 

 and abundance of untreated host plants in the vicinity, weather 

 conditions, varieties, the presence of succulent water sprouts, 

 natural enemies on nearby host plants and in the orchard, and the 

 spray program. Early spring control of all aphids is strongly rec- 

 ommended . 



For best aphid control, use Guthion*or ethion with oil or a 

 formulated ethion-oil mixture at hgif.inch green, or Guthion* or 

 demeton up to pink. 



