1708 



SPRAYING 



m 



2371. 



Splint broom 

 for applying 

 spray. 



An early de- 

 vice. 



LeBarron, state entomologist of Illinois; William Saun- 

 ders, London, Ontario, Can. ; J. S. Woodward, Lock- 

 port, N. Y.; T. G. Yeomans & Sons, Walworth, N. Y.; 

 Professor A. J. Cook, Agricultural College, Mich. 



Following Paris green came London purple, and then 

 white arsenic. Since that time many different forms of 

 arsenical poisons have been compounded, 

 offered to the public and frequently used. 

 London purple has now been largely 

 dropped by fruit - growers, owing to its 

 variable quality. White arsenic, used in 

 combination with soda and with lime, 

 forms at the present time reliable and 

 widely used insecticides. 



While sucking insects were instrumental 

 in bringing about the invention of many 

 formulae, it has only been within the last 

 twenty-five years that an effective method 

 has been devised for their treatment. Al- 

 though kerosene has been recommended 

 and used to some extent for thirty-five or 

 more years, it was not until Cook recom- 

 mended kerosene in the form of a soap 

 and water emulsion that a desirable, eas- 

 ily prepared oily insecticide was found. 

 About the same time, Dr. Riley, with Mr. 

 Hubbard, of the Department of Agricul- 

 ture at Washington, recommended the use 

 of what is now known as the Riley-Hub- 

 bard formula. 



The potato bug invasion and the dis- 

 covery of the efficacy of Paris green in de- 

 stroying leaf-eating insects did a great 

 deal to stimulate spraying, but due credit 

 should be given plant pathologists for 

 tracing the life-histories of many fungi 

 destructive to cultivated plants. 



fungicides. Early in the eighties dis- 

 eases of grape-vines threatened the ex- 

 tinction of French vineyards. The situa- 

 tion engaged the attention of French investigators. 

 Notable among them were Professor A. Millardet and 

 his co-workers of the Academy of Science, Bordeaux, 

 France. He, with others, discovered partly by acci- 

 dent and partly by experiment that solutions of cop- 

 per prevented the development of downy mildew. 

 After much experimentation, "bouillie Bordellaise" was 

 found to be effective in preventing the growth of downy 

 mildew and other plant parasites infesting the grape in 

 that region. The announcement was definitely made in 

 1885. The following year the European formula for 

 Bordeaux mixture was published in several places in 

 the United States, and immediately there commenced an 

 unparalleled period of activity in economic vegetable 

 pathology. The establishment of the U. S. experiment 

 stations gave added impetus to the movement. The 

 rapidity of the spread of spraying knowledge among 

 fruit-growers is remarkable. Ten years ago it was an 

 unknown art by the rank and file. To-day agricultural 

 clubs and granges purchase their spraying materials 

 by the car-load direct from the manu- 

 facturer. . The American farmer leads 

 his fellow- workers in all parts of the 

 world in the practice of spraying. Al- 

 though Bordeaux mixture was dis- 

 covered in Europe, its application has 

 been made practicable by American 

 inventions. 



The Principles of Spraying. A 

 spray may be effective (a) by hitting 

 the enemy, ( b ) by placing poison before 

 the depredator, and (c) by protecting 

 the plant with a covering unfavorable 

 to the growth of the pest. The cau- 

 tious farmer insures his crop against 

 injury by insect or vegetable para- 

 site by spraying. The fruit-grower 

 asks, "Do I need to spray this year? 

 My trees are not blossoming." Cer- 

 tainly, we answer, spray to protect 

 the foliage from possible injury by in- 

 sect or fungous disease. Healthy foli- 

 age is essential to the production of 2372. A bucket 



SPRAYING 



health and vigor and fruit-buds. Spray this year for 

 next year's crop. 



Insecticides kill by contact or by means of a poisonous 

 principle ; their efficiency depends largely on the time 

 and thoroughness of the application. If applied too soon 

 they may be dissipated before the insects appear; if 

 applied late the injury is only partly prevented, because 

 insects feed less voraciously and are harder to kill as 

 they approach maturity in the larval stage. With the 

 vegetable parasite the case is not essentially different. 

 The tree is covered with a thin coating which destroys 



2373. Knapsack pump. 



spores of fungi resting there and prevents other spores 

 from germinating. Fig. 2370 shows the stage of develop- 

 ment of fruit-bud calling for Bordeaux mixture and Paris 

 green. The keynote to success is thoroughness. Hasty 

 sprinklings are worse than useless; they discourage and 

 disappoint the beginner. Full protection is not afforded 

 unless each leaf, twig and branch has been covered. Time 

 is the next most important factor bearing on success. The 

 early spray is most effective. This applies particularly 

 to the treatment of fungous diseases. Spray before the 

 buds open. Get ahead of the enemy. 



Spraying Machinery. Bordeaux mixture was first 

 applied with a broom (Fig. 2371); now there are not a 

 few steam sprayers in use. Poison distributors were first 

 made in America for the protection of cotton, potato 

 and tobacco. There are five general types of pumps: 



(1) The hand portable pump, often attached to a pail or 

 other small reservoir, suitable for limited garden areas. 



(2) The knapsack pump is carried on a man's back and 

 operated by the carrier. The tank is made of copper, 

 holds five gallons and is fitted with a neat pump which 

 may be operated with one hand while the nozzle is di- 

 rected with the other. Excellent for spraying small vine- 

 yards and vegetable gardens. (3) A barrel pump: a 

 strong force pump fitted to a kerosene barrel or larger 

 tank, suitable for spraying orchard areas up to 15 acres in 

 extent; may be mounted on a cart, wagon, or stoneboat, 

 depending on the character of the ground and size of 



trees. (4) A Gear-sprayer; beingatank 

 provided with a pump and mounted on 

 wheels. The pump is operated by power 

 borrowed from the wheels as they 

 revolve, and transferred by means 

 of chain and sprockets. Suitable for 

 vineyards and low -growing plants, 

 which may be satisfactorily covered 

 by the spray as the machine moves 

 along. For this reason it is not adapted 

 to orchard work. (5) The power 

 sprayer ; power being furnished by 

 steam, gasoline, or compressed air. 

 When the trees are large and the or- 

 chard over fifteen acres in extent, a 

 power sprayer will usually pay. Some 

 of these various types of machinery 

 are shown in Figs. 2372-2379. 



The essentials of a good pump are 

 ( 1 ) durability : secured by having brass 

 working parts (copper compounds cor- 

 rode iron); (2) strength: obtained by 

 a good -sized cylinder, substantial 



