-2- 



abundant predatory enemies are the lady beetle, Stethorus punctum, and the 

 predatory mite Seius pomi, although thrips and a predaceous bug are also 

 active enemies. 



ilormal winter eggs are bright red and summer eggs are pale straw 

 color. Any white appearing or dull light colored "eggs" are usually the 

 shells from hatched mites or eggs from which the contents have been sucked 

 by predatory enemies. Heavily infested trees are seldom badly infested the 

 following year because the natural enemies are very active late in the season 

 and the mites usually migrate from badly bronzed foliage which lacks suitable 

 food. An adjacent block of trees is more likely to be infested the second 

 year. 



Red mites are strongly influenced by weather and although an abundance' 

 of winter eggs will provide a source for an early infestation, unfavorable 

 weather or a plentiful supply of natural enemies may prevent noticeable damage 

 to the foliage, before midsummer. On the other hand, mites spread by the wind 

 or by birds may develop by late summer into a destructive infestation on trees 

 which bore relatively few winter eggs. Hot dry weather is favorable to rapid 

 multiplication of red mite, and rain and cool weather delay the increase of 

 this pest. Heavy rain storms such as thunder showers frequently knock thou- 

 sands of mites from the leaves and may prevent an infestation from becoming 

 serious. 



Lime sulfur (liquid) 1-50 kills red mite and when this material was 

 generally used in pre-blossom sprays many potential infestations were pre- 

 vented. Wettable sulfur or sulfur dust does not kill red mite effectively; 

 in fact, it kills the natural enemies of the red mite mors easily than it 

 does the pest. The available summer sprays are not very satisfactory. Ro- 

 tenone sprays and dusts are too expensive; soap is d\fr?cult to apply, and 

 nicotine is not effective. Last year, modified forms vf DN sprays and dusts 

 appeared very promising and it is hoped that they will supply the answer to 

 this troublesome problem. On the basis of our present knov^rledge, hov;ever, 

 the wise fruit grower will apply a dormant or delayed dormant spray on trees 

 Vi'hich bear a heavy population of v;inter eggs of the red mite and spray most 

 of his orchard in this way about once in each 3 years. To date, the summer 

 troatmcnts should be considered as emergency sprays which should be used only 

 to prevent excessive bronzing of the foliage. W. D. Vifhitcomb 



Co dlin g Moth , - A pple Enem y No. 1 



The codling moth is the most serious insect pest of apples in the 

 country. It is claimed tliat this insect causes a loss of 12 to 15 million 

 dollars annually to the commercial apple crop. In addition, it is estimated 

 that we pay 3 to 5 million dollars a year to spray the orchards of the country^ 

 ■to check this pest. The apple is the favored host and all varieties are at- 

 tacked, but pears, peaches, and quinces may be infested. 



The codling moth passes the winter as a full-grown larva within a 

 tightly woven cocoon. These cocoons may be fnund under rough bark, around 

 old pruning scars, and other crevices on the trees. They are often found in 

 old boxes in or around packing houses and storage sheds. Prop poles, piled 



I 



