Hie Canadian Horticulturi^ 



Vol. XXXVII 



FEBRUARY, 1914 



No. 



Why, When and How Wc Spray 



M. B. Davis, B.S.A., Bridgetown, N.S. (Manager Sunnyside Farm Ltd.) 



Spraying is probably the most scien- 

 tific and complicated operation in con- 

 nection with fruit growing, yet how often 

 it is conducted in a careless manner, re- 

 sulting in poor success and a waste of 

 money. 



The first spraying we make is about 

 the first of March, the dormant spray. 

 This application is made to combat scale 

 insects such as the oyster shell bark 

 louse and the San Jose Scale. It consists 

 of lime-suphur solution of the strength 

 1.03 specific gravity. This has proved 

 an efficient check in the control of the 

 scale insects. In old neglected orchards 

 it should be made every year. 



Our next spraying, or second applica- 

 tion, takes place just as the leaf buds 

 are bursting out green. This time we 

 use lime-sulphur of the strength of i.oi 

 specific gravity and two pounds of lead 

 arsenate to every forty gallons of the 

 lime-sulphur wash. The lead not only 

 acts as insecticide, but it also increases 

 the fungicidal value of lime-sulphur. In 

 fact, lime-sulphur when used alone has 

 not proved a thoroughly reliable fungi- 

 cide, whereas with lead arsenate added 

 it has given consistently good results. 



It might be well to mention at this 

 point the importance of using the tri- 

 plumbic or neutral arsenate of lead in- 

 stead of the acid arsenate. A very large 

 per cent, of the burning found in or- 

 chards whore lime-sulphur has been used 

 is caused by the acid arsenate and not 

 by tlie lime-sulphur. The acid arsenate 

 is a lead which carries a much higher 

 oer cent, of arsenic oxide than does the 

 neutral lead. Hence the reason why 

 nany are gulled into purchasing it, for 

 he arsenic is the product w hich does the 

 wisoning. But, although the neutral 

 ead has less arsenic per pound, it is 

 .afer to use. The acid arsenate, con- 

 aining as it does a certain per cent, of 

 ree arsenic or arsenic acid, is found to 

 Ijive unsatisfactory results. So beware 

 :)f this product when you purchase. 

 THIKD SPRAYING 



Our third spraying and also the fourth 

 ne are probably the most important ones 

 ye make for the control of apple scab. 

 >cab is a disease which spreads by 

 pores, and these spores will germinate 

 nd produce the di.sease in from twelve 

 o twenty-four hours under proper con- 

 litions, which are henf and moisture. A 



fungicide can only prevent the germin- 

 ation of these spores ; it cannot prevent 

 or cure the scab after it has once started. 

 The only way, therefore, to keep fruit 

 clean is to keep the spores from germin- 

 ating on it from the time it is formed. 

 The third spraying, applied as it is just 

 before the buds show pink, prevents 

 these spores from getting a foothold on 

 the pistil or ovule. The fourth spraying, 

 which is made just as the blossoms are 

 falling, will keep the young apple, or 

 fertilized ovule at the base of the pistil, 

 free of disease. These sprayings must 

 be made on time, and that time can only 

 be set by the time the different varieties 

 bloom. 



Many growers find the Gravenstein an 

 apple impossible to keep clean . Why? 

 Because by the time the rest of their 

 trees are in bloom this variety is out, and 

 as they wait for the later ones before 

 spraying, the Gravenstein is missed 

 every time. Get after the early ones by 

 themselves. Don't wait. Be on time 

 and you will see better results. 



It is not so much how to spray, but 

 when to spray, that counts in the pack 

 out in the fall. These sprayings not 

 only assist in keeping the fruit clean, 

 but they ensure you a good crop, for if 

 the young apple becomes affected with 



scab it withers up and falls off. A great 

 deal of the so-called poor pollination or 

 blossoms not setting good is nothing 

 but scab being on the young ovules and 

 sapping out its life. This is another 

 reason why you should get there on the 

 dot. Keep the young fruit and all new 

 surface coated with spray so that no 

 spores will get an opportunity to ger- 

 minate. 



The fifth spraying we make about 

 three weeks after the fourth spraying, 

 and this may be followed by another. 

 Two years ago we sprayed up to Aug- 

 ust loth, and got results from our late 

 sprayings. The latter part of the sum- 

 mer was so damp that the fruit began to 

 spot very late, and people who had spot 

 under control during the first part of 

 the summer became overwhelmed with it 

 later because they neglected to spray. 

 The apples had formed a lot of new sur- 

 face for the spores to develop on, as this 

 new surface was not coated with spray. 

 Orchards which were sprayed well at 

 first and which were clean in July, were 

 dirtier in the fall than orchards neglect- 

 ed at first but cared for later, and it was 

 simply on this account. Do not be afraid 

 to keep up spraying. Let the good work 

 go on, and if you have a damp season 

 drive the spray pumps right along. 



Up-to-date Method* a* Applied in a Nova Scotia Orchard 



—Photo by Eunice Buolianan. 



