STATE POMOLOGICAL SOCIETY. 113 



which the spores are matured and bring about infection, is 

 when the buds which contain blossoms and leaves, begin to 

 show pink. That is the stage, just before the blossoms open, 

 when you usually have the first infection from apple scab. The 

 spores on the ground are shot into the air, and carried by the 

 breeze through the orchard. Some of them falling on these 

 leaves or blossom stalks infect the tissue, form a scab spot and 

 bring about the injury. 



Now the ideal time to make the first application for scab — 

 you have already made the dormant spray for other things — 

 is just when those blossom buds are beginning to spread apart; 

 the leaves will all be turned back and the blossoms will have 

 just pulled apart; the middle blossom at least will show pink, 

 the others usually do. Now the ideal period does not last 

 more than a day or two at most, so that to spray effectively, 

 most effectively, you should be able to spray your entire or- 

 chard, or at least all the varieties that are in that condition 

 within one or two days' time. There are very few orchardists 

 who have orchards of any size, who are prepared to do this. 

 We have figured that no orchardist should expect to effectively 

 spray his trees with less than one power machine for ten acres 

 of orchard, 

 --. Question: Why not spray the ground. 



Prof. Whetzel: Because the spores are inside of the leaves 

 and the spray mixture will not reach tlie spores. The water 

 will go through the leaf but the poisons that kill the spores 

 will be left on the outside, filter out, and the spore case in 

 which these spores are contained will open up and shoot the 

 spores into the air just the same. We have found that you 

 may soak a bunch of diseased grapes in strong blue vitriol, and 

 it will yet continue to produce active spores. There is nothing 

 to be gained by spraying the ground. Your first spray should 

 be thorough and eft'ective. It should be put on as a fine spray 

 with at least 200 lbs. pressure. It should be put on ahead of 

 the rain periods that come at that time, not after the rains. 

 You should spray against the wind when you put it on. I 

 won't stop to explain that now because it would take too long, 

 but the most efficient way to spray is against the wind. The 

 next application should be made just after the blossoms fall. 

 When two-thirds of the blossoms are off the trees the average 



