Page 6 



BETTER FRUIT 



February, 1921 



Orchard Spray Program for 1921 



THERE are two objects in spraying. 

 One is to coat all parts of the tree 

 or fruit so thoroughly that no 

 fungus or insect can find any spot that 

 is not protected by a layer of poison. 

 The other is to destroy the pests or par- 

 asites present by hitting them with the 

 proper kind of poison at a stage when 

 they are defenseless against it. Spray- 

 ing is a preventive. It cannot cure 

 damage already done. 



Spraying cannot be effective unless 

 adapted to the life-habits of the para- 

 site and the condition of the tree and 

 fruit. Yet many growers apply sprays 

 uselessly at times when little real good 

 can be done and then fail to spray at 

 the critical periods when they could get 

 results. Other growers fail to do the 

 work thoroughly enough to reach all 

 insects, or to coat all susceptible parts 

 of the tree. Slill others use wrong ma- 

 terials. Success can be expected only 

 from the thorough application of the 

 right sprays at the right time. 



General Hints. 



Care of the Young Orchard: If free 

 from disease and insect pests when 

 planted, young orchards seldom re- 

 quire any regular schedule of sprays. 

 Thorough inspections should be made, 

 however, at frequent intervals. All 

 kinds of fruits should be watched for 

 the invasion of San Jose scale or other 

 scale insects, aphids, borers, bud wee- 

 vils, fruit caterpillars and Armillaria 

 root rot. In apple orchards look also 

 for mildew, anthracnose, fire blight, and 

 wooly aphis; in pears, for fire blight, 

 slug, and blister mite; in peaches, for 

 leaf curl, mildew, blight, and twig 

 miner; in prunes and plums, for leaf 

 spit, spider mite, bark beetles and 

 borers; in cherries, for bacterial gum- 

 mosis, leaf spot, slug, and shot-hole 

 borer. When any of these troubles are 

 found, follow out the recommendations 

 outlined for them in the regular spray 

 schedule. 



Pruning: Pruning should be con- 

 ducted in such a way as to let light and 

 air into the interior of the tree. This 

 favors rapid evaporation of moisture 

 from leaf and fruit, and thus tends ma- 

 terially to hinder fungous infections. 

 While pruning, inspect the trees for 

 San Jose scale, woolly aphis, and other 

 pests and diseases. Remove all mum- 

 mied fruits from the orchard. Where 

 bacterial gummosis or fire blight is 

 present always sterilize pruning instru- 

 ments and cuts with some good disin- 

 fectant to prevent spreading the dis- 

 ease. 



Spray Outfit and Nozzle: An ade- 

 quate (Hillil is necessary for best re- 

 sults. In power spraying a pressure of 

 175 to 225 pounds is advisable with 

 rod and nozzle equipment. The angle 

 nozzle of the disc type, using a disc 

 with ;i small opening, gives general sat- 

 isfaction. This delivers the fine, misty 

 spiny desired and affords ease of ma- 

 nipulation in applying the spray from 

 different directions. Two of these noz- 



By H. P. Barss and A. L. Lovett 



zles on a Y at the end of a rod, by de- 

 livering more solution, increase the 

 speed and thoroughness of application. 



Use a Tower: In spraying larger 

 trees satisfactory control of insects and 

 diseases in the upper third of the trees 

 is next to impossible without the use 

 of a tower. 



Advantages of the Spray Gun: The 

 new "Spray Gun" type of nozzle has 

 met with general favor. This is a very 

 compact outfit, easy to manipulate and 

 delivering a large quantity of liquid. 

 Powerful pressure is essential for the 

 proper functioning of a spray gun, a 

 force of 250 to 300 pounds being ad- 

 visable. Engine troubles commonly de- 

 velop, with the use of the gun, from 

 speeding up the engine where the 

 power and capacity are insufficient to 

 maintain a reserve when in action. The 

 spray gun does its best work on the 

 highest powered outfits. With such an 

 outfit in the hands of a careful manipu- 

 lator, spray may not only be applied 

 practically as well as with the exten- 

 sion rods, but much more rapidly and 

 with less fatigue. 



Lime-Sulphur Injury: Lime-sulphur 

 should not, as a rule, be applied after 

 early June, in apple orchards, because 

 of the burning that often results when 

 hot, bright weather prevails. Self- 

 boiled lime-sulphur is recommended as 

 a substitute under conditions where or- 

 dinary lime-sulphur is liable to injure. 

 Even as dilute as 1 to 45 lime-sulphur 

 may cause injury in warm weather to 

 prune fruit and foliage and it is unsafe 

 to use on peach foliage at any time. 



Local Variations: Climate has a tre- 

 mendous influence on the severity of 

 insect and fungous attack and on the 

 time when the attacks occur. Hence 

 the marked variations in climate from 

 season to season and the difference in 

 temperature, rainfall, etc., in different 

 sections of the state will naturally 



make some modifications in the time of 

 application and number of sprays re- 

 quired to obtain best results. The rec- 

 ommendations in this article are adapt- 

 ed most closely to the average condi- 

 tions prevailing in the large fruit 

 growing areas from the Cascades west 

 and from the Valley of the Umpqua 

 north. To the east and south, where 

 rainfall is less abundant, fungous dis- 

 eases will, in general, be less severe 

 and will require fewer fungicidal 

 sprays for control. This favorable cir- 

 cumstance need not be true of insect 

 pests and their control. Some fruit 

 sections are so fortunate as to have the 

 services of a trained specialist familiar 

 with the diseases and insect pests and 

 with local conditions. Growers so fa- 

 vored, should by all means obtain the 

 available, consult the college. 



Pointers on Spray Materials. 



Many varieties of commercial spray 

 materials are on the market, some of 

 them for general use, many of them for 

 special purposes. Most of these mate- 

 rials are very good when properly used; 

 some are of questionable value when 

 price and purpose are considered, and 

 a few are really dangerous. As a rule 

 the commercial preparations of the 

 various spray materials recommended 

 in this article are standardized, are 

 more convenient to use, and often as 

 cheap as the home-made sprays when 

 the labor and equipment necessary for 

 home preparation are considered. It is 

 important that the material, if a com- 

 mercial product, be pure and fresh. It 

 should be in the original unopened con- 

 tainer and should not have been allowed 

 to dry out or to freeze. 



Lime-Sulphur: Wherever the word 

 "lime-sulphur" is used in this article it 

 refers to the ordinary commercial con- 

 centrated lime-sulphur solution, testing 

 approximately 32 degrees Baume. The 



Applying Spray from Horse-Drawn Rig. 



