12 



The valleys here considered are those which lie at an altitude of 300 

 to 1,000 feet above the sea level, includino- practically all of the regions 

 in which the peach thrives, and which in the main are cultivated under 

 irrigation. In these valleys commercial fruit growing is, perhaps, 

 more extensively engaged in at present than anywhere else in the 

 Pacific Northwest. 



The extremely favorable conditions, so far as pests are concerned, in 

 these inland valle3^s lies in the absence of any serious fungous disease. 

 Apple and pear scab do not occur;, brown rot is reported from but one 

 locality; blackspot canker is unknown. How far these conditions are 

 due to climate, and how far to comparative isolation, is difficult to 

 determine. The experience of most of the older fruit-growing commu- 

 nities is a warning to the fruit grower that there is little ground for 

 hope of immunity from any particular pest on account of climatic influ- 

 ences. The absence of such serious enemies as peach yellows, brown 

 rot, and plum curculio, not to mention others, is an important factor 

 in successful orcharding in these valleys. 



INSECT ENEMIES. 



The following are the insect pests of most importance: 

 San Jose scale. — The first appearance of this insect in the Northwest 

 seems to have been in the Snake River Valle}^ at Almota. At the 

 present time the insect is abundant in most of the valleys and occa- 

 sional on uplands. The universal practice is to spray in winter with 

 the sulphur-salt-lime wash, which is completely efiective when properly 

 applied. Excepting that such winter applications entail a perennial 

 expense, the advent of the insect has caused little damage. An inci- 

 dental feature gained in peach orchards by these winter sprayings is 

 the control of the peach-leaf curl, which occasionall}^ caused consider- 

 able damage. 



Codling moth. — Taken all in all this is the worst insect pest in the 

 Northwest, and it is more destructive in these inland valleys than else- 

 where. Owing to the long warm season, the insect may be found at 

 almost any time, and in all stages, from May to September. It is 

 commonly believed that in these valle3's the insect has three or more 

 annual broods, but this is by no means demonstrated. The experience 

 of fruit growers has led them to sprav from five to seven times each 

 season to control this insect. The majority of orchardists use Paris 

 green, but others secure as good results apparently with the cheaper 

 arsenite of soda mixture. The sprayings as carried out by most grow- 

 ers are as follows: The first, just as soon as the petals fall; the second, 

 two weeks later; the third, about 'luly 10, and the remaining sprajdngs 

 at intervals of two to three weeks, the last one being in September. 

 A few growers supplement their spraying with the " banding system," 

 and believe that the results secured justify the practice. 



