102 REPORT OF STATE BOARD OF HORTICULTURE. 



Speaking of frosts, we learned that it is impossible to locate 

 any spot exempt from it, but all orchards are not always in- 

 jured, as the blooming varies materially even in orchards 

 close to each other. Frosts, however, seldom do any damage, 

 except during pollination ; after the fruit has set it will stand 

 quite a freeze, Mr. McPherson, Horticultural Commissioner 

 for Idaho, tells us that often in sj)ring fruit and leaves are 

 frozen stiff, but for some unknown reason they generally thaw 

 out without injury. 



INSECTS AND DISEASES. 



Of insects there are the San Jose scale, green aphis, and 

 red spider, which, however, are easily controlled now by ap- 

 plying remedies given by our bulletin and reports ; but by 

 far the greatest enemy is the codling moth, of which they 

 have some three and one-half broods per season, owing, no 

 doubt, to the warm nights which prevail during the season. 

 The band system is used extensively, and spraying followed, 

 religiously, but the best results have only been obtained by 

 those who persistently watched and examined the band every 

 week, as the larvae develops in about that period, and sprayed 

 almost continuously — many growers going over their orchards 

 twice and three times in succession when the apple has at- 

 tained the size of a hazelnut and before the calyx closes, so 

 as to fill this place full of poison for any codling moth larv8& 

 which may find its way there, the usual point of attack, many 

 orchardists going so far as to pick off all wormy fruit. 



We further found that along the foothills of the Grande 

 Ronde Valley, notably near Cove, the codling moth has not 

 obtained foothold, very few apples there being wormy. This 

 is no doubt attributable to the cool nights prevailing there the 

 year round. As regards the development of the moth, there 

 is a vast difference between the Grande Ronde and the Snake 

 River districts. The codling moths are more severe in the 

 Boise River Valley and its tributaries than any part of the 

 fruitgrowing district of the Northwest. In the Grande Ronde 

 Valley, however, the injuries from it are as light as anywhere, 

 except directly on the coast line, where the moth does not 

 propagate at all, which is evidently due to climatic conditions. 



As stated before, we have been unable to find any apple 

 scab or pear blight, or even the dreaded apple canker or dead- 

 spot, but have found the crater blight of the pear quite seri- 

 ous, and unless taken in hand at once and stamped out it 



