-7- 



Hatching scarts soon after fruit buds start to show green, later than the 

 grain aphid, but earlier than rosy aphid. In 7-10 days hatching is complete 

 and the nymphs are sucking sap from the new growth of leaves, stems and flower 

 parts. At this time, the green ap^ple aphid usually is outnumbered by the grain 

 aphid and no injury is seen. 



The growth of these first generation nymphs into stem mothers is completed 

 in 2 to 3 weeks, sometime about Pink or a few days earlier. These stem mothers 

 are a uniform pale green easily distinguished from grain and rosy aphids. 



Shortly before bloom the stem mothers, without mating start to produce 

 living young. This process may continue for a month or more at a rate of 1 to 

 3 (naximum 10) nymphs per day. 



From 60 to 75 per cent of these second generation nymphs develop wings, 



migrate to new leaves, terminals, or threes and there produce living young 



the beginnings of new colonies. The wingless forms in each generation simply 

 produce living young, thus greatly increasing the numbers of aphids at their 

 original colony site. 



From 10 to 17 generations have been recorded in a season, all of them on 

 apple or related plants. 



Thus we see, in the green apple aphid, a much less complicated life cycle. 

 All the generations may occur on apple. Also, they contain only winged and wing- 

 less, non-mating females, capable of bearing living young, except for the fall 

 generation of sexual, wingless forms that mate and lay the overwintering eggs. 



The green apple aphid will bear close-watching until maturing terminals 

 slow down their rate of increase. 



Control 



SPRING ; "Insurance" programs carried out over the x^hole farm w ill prevent 

 all worry about green apple aphid until July. The severity of reinfestation 

 will then depend upon the nearness and abundance of untreated host plants in 

 the vicinity, weather conditions, varieties, presence of succulent water 

 sprouts, abundance of natural enemies on nearby host plants and in the orchard, 

 and your spray program. 



Early spring control of all aphids is strongly recommended for lead 

 schedule orchards. The dinitros would be the least destructive to beneficial 

 insects. 



Any one of the "insurance" programs suggested for rosy aphid should be 

 adequate for early green apple aphid control in all orchards on the organic 

 insecticide schedule. 



SUMMER ; The summer build-up of green apple aphid becomes noticeable in 

 June and may continue well into July in favorable seasons. 



