The Pro"blen of "Mcintosh Drop ." 



A rather intensive investigation in the College Orchards in Am- 

 herst hps revealed that dropping just prior to harvest vrries from year to 

 year with the same tree, from tree to tree within the same hlock, RJid from 

 limh to limt in an individual tree. The actual cause of dropping can he 

 directly traced to the development of r-n ahscission zone on the spur. But 

 the petrticiilar conditions which initiate the formation of this highly 

 specialized layer are not exactly known. It is tho-ught "by many pomologists 

 that environmental conditions at critical periods must exercise important 

 influences. Thus, high temperatures during a particulpj period increased 

 the dropping of Mcintosh in New Jersey in 193^ over some other years. Tlien 

 again, the farther south an orchard is located in the Mcintosh "belt, the 

 more severe the dropping prohlem. Massachusetts is thus more or less 

 favored in location. Here at Amherst we have not "been able to correla.te 

 definitely ajiy particiilar environmental condition or conditions with 

 severity of pre-harvest dropping. However, we have found that seed con- 

 tent is important, pro'ba"bly as it influences the formation of vp.scular 

 tissue. As a general rule, the early drops contain fewer fully developed 

 seeds than those apples that hold on, suggesting the significance of pro- 

 per and sufficient pollination of the apple "blossom. To give just one 

 exajnple, using data, from a. twelve-yepx tree, the apples that dropped from 

 the 10th to the 15th of Septem'ber contained on the average less than five 

 seeds. Those that dropped during the next five days revealed approximately 

 six seeds per a,pple, and those that hung on until after the 20th of 

 September averaged more than eight seeds. 



In addition to greater color development, a further vital consi- 

 dera.tion is that an apple usually increa.ses in size as long as it remains 

 on the tree, within certain limits, of coiirse. Thus, data from ajiother 

 tree in the same "block reveal that those apples that htmg on the tree until 

 the last of September had increased over 355" i'^ voliime over those that 

 dropped during the first week. Naturally, the practical importance to the 

 grower is evident. If he could delay picking without seriously increas- 

 ing the amount of dropping, the advantage would "be tremendous, 



(Lawrence Southwick) 

 Bees and Mcintosh Pollination 



Seven years a^o this spring, a New Englajid grower of Mcintosh 

 wondered about the importance of bees and cross pollination in the setting 

 of a. crop. And so "tents" of. tobacco cloth were placed over two promising 

 15-year old trees just before the blossoms opened. Two similar, nearby 

 trees were selected as checks,- As a result of this test, bees were en- 

 tirely excluded from the first tree during the blooming period, while a, 

 bee or two must have entered the second tent throught a hole which was 

 later discovered. In the ca.se of the third and fourth trees, the bees 

 were able to carry on their work without ajy interference. All trees bloomed 

 heavily. 



