520 ANNUAL REPORT OF THE Off. Doc. 



Very few persons iu the State have found the past season fav- 

 orable for the potato crop, continued drouth through the most of 

 the growing season being tlie cause. The most destructive en- 

 emies in usprayed fields are blight and the Colorado beetle. When 

 thoroughly and frequently sprayed there need be no loss from either. 



Many persons have learned to control potato scab, the most 

 favoreid way being to soak the seed for one hour and a half in a 

 solution of two onces of corrosive sublimate to sixteen gallons of 

 water. Formalin, or formaldehyde, can be used in the same way, 

 one pint to sixteen gallons of water. 



A few of our reports recommend planting potatoes in checks, 

 thirty by thirty inches up to forty by forty inches, but most persons 

 prefer to plant in rows varying from twenty-four to forty-two inches 

 apart. Thirty-six inches is most favored and is well adapted to 

 cultivation and spraying with two horse tools. Some growers plant 

 as close as ten inches in the row, others up to twenty inches, more 

 correspondents preferring twelve inches than any other distance. 

 A good number named fifteen inches, which we believe to be about 

 right under most conditions. 



SPRAYING. 



We are glad to report that spraying for insects and fungi seems 

 to be steadily increasing, but we are sorry indeed to report the de- 

 plorable fact that seventy per cent, of our correspondents tell us 

 that spraying is not thoroughly done. Until this condition is over- 

 come and the percentage at least reversed, our State cannot expect 

 to make much progress in its war against these enemies. We will 

 venture the assertion that fruit growers in the Hood River Valley 

 of Oregon could report 100 per cent, of thoroughness and that in 

 this very matter of thoroughness lies the secret to their great suc- 

 cess. 



Reports seem to indicate that only in districts where fruit grow- 

 ing is followed, at least to some extent commercially are grow- 

 ers awake to the possibility of controlling the codling moth. We 

 are much interested in the extent to which arsenate of lead has 

 replaced Paris green as a spray for this insect. Its adhesiveness 

 is, of course, the feature which recommends it so strongly. Many 

 jK'rsor.s use arsenate of lead combined with Bordeaux deriving ex- 

 cellent results from both. 



Scale seems to be held in check, at least to a considerable de- 

 gree. We believe that the sections from which failure is reported 

 are lacking in thoroughness of work. Many of our careful men 

 write, "We no longer dread San Jos6 Scale." 



In answer to the question ''What is the most satisfactory and 

 effective scale spray you haA'^e used?" the answers were as follows: 

 Lime-sulphur wash 2G, Commercial Soluble oils 23, divided as fol- 

 lows; Scalecide 17, Target Brand Scale Destroyer 3, unclassified 

 3. Two persons recommend the use of kerosene. It is not our pur- 

 pose to make any recommendation but rather to emphasize again 

 our belief that in careful and thorough spraying lies the key to 

 success in controlling San Jos^ Scale. In a great many cases an 

 effort to economize material has resulted in most dismal failure. 

 We are frequently told that soluble oils should be sprayed with 

 very fine nozzles and we believe it is a matter of vital importance 

 in their use. 



