PREVENTION OF THE APPLE SCAB 



k 4 ^ I ^ HERE is no question of more vital 

 X interest to the general fruit grower 

 than that of the apple scab. The prime 

 question is, Under vhat conditions of care 

 and management of orchards can it be re- 

 duced 'o a minimum? The bottom of this 

 question has not yet been reached, conclu- 

 sions up to this time being empirical, rather 

 than based on sufficiently wide facts." 



These remarks, made to The Horticul- 

 turist recently by Mr. A. W. Peart, of Bur- 

 lington, led to an attempt being made to ob- 

 tain the views, on this subject, of a number 

 of well known authorities, including both 

 practical growers as well as experimenters. 

 The majority of those heard from, it will be 

 seen, advocate thorough spraying and judi- 

 cious thinning as the best means of prevent- 

 ing the scab. 



" I have," writes Joseph Tweddle, of 

 Fruitland, " obtained the desired results in 

 regard to preventing apple scab by thin- 

 ning the bearing parts of the tree to let in 

 plenty of light and air, and by spraying 

 all parts of the tree. Spray thoroughly 

 with Bordeaux once before bloom and at 

 least twice after. Give the second applica- 

 tion just after the bloom falls, the third two 

 weeks later, and follow with a fourth, should 

 long continued rains of two days or more 

 take place. The mixture should be applied 

 quickly after rain, from each side of the tree 

 as the wind changes. It is necessary that 

 the work should be done thoroughly." 



iVluch the same views were given by Mr. 

 W. H. Dempsey, of Trenton, who states 

 that he has had good results from the Bor- 

 deaux mixture in keeping the apple scab in 

 check whenever it was applied carefully 

 and at the proper time. Mr. Dempsey has 

 noticed that Fameuse apples sprayed care- 

 fully just before the bloom opened gave 

 better results than those sprayed only after 

 the bloom had fallen. It is not safe to neg- 

 lect spraying, which should be done three 

 times, once before bloom and twice after. 



The practice of Mr. .-\. E. Sherrington, 

 of Walkerton, is to give clean and thorough 

 cultivation to impart a vigorous and thrifty 

 growth. With this, judicious pruning is 

 done annually so as to let the light and air 

 circulate freely through the trees. Last, 

 but by no means least, Mr. Sherrington 

 sprays thoroughly and systematically. He 

 does not believe in drenching the trees, but 

 in applying tlie spray in as fine a mist as 

 possible. Were more growers to do this, 

 ^Ir. Sherrington believes, the apple scab 

 would be reduced to a minimum. 



WHAT THE EXPERIMENTERS SAY. 



The views of several well known experi- 

 menters secured, include those of Prof. L. 

 R. Taft, of the Michigan Agricultural Col- 

 lege, Lansing, Mich. ; Prof. John Craig, of 

 the Cornell College of Agriculture, Ithaca. 

 N. Y., and Prof. H. L. Hutt, of the Agri- 

 cultural College, Guelph, Ont. Their 

 opinions are here given : 



Prof. L. R. Taft : The extent of the in- 

 jury to apple trees by scab is determined, to 

 a large degree, by the climatic conditions, 

 alt-.ough the age and condition of the trees 

 have much to do with it. Our growers, 

 who have practiced thorough spraying of 

 their apple orchards with Bordeaux mix- 

 ture, have had comparatively little trouble 

 from it. Orchards on rolling land and 

 with trees pruned so as to give fairly open 

 heads are much less injured than those on 

 low land or in hollows. When the trees 

 are sprayed it is advisable to make at least 

 one application before the blossoms open, 

 preferably at the time the petals begin to 

 show. A second spraying should be given 

 as soon as the petals begin to fall, and a 

 third at the end of about two weeks. Ordi- 

 narily this will suffice until the latter part 

 of July, when a spraying of Bordeau mix- 

 ture and an arsenite is advisable to prevent 

 injury by the apple scab as well as the at- 

 tack of the second brood of codling moths. 



Some of our growers are making use of 



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