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nutrition program was followed to help the tree to recover. A 

 few growers who used soil injections with root feeding solutions 

 claimed that it did help a great deal. In many cases irrigation 

 has also helped tremendously. 



The winter of 1980-81 did more harm to pear, plum and cherry 

 trees than it did to apple trees. The pear cultivars or selections 

 which suffered most from cold injury were Bartlett, Beurre Bosc, 

 Highland, 0-361, H-68- 31-1- 12 , HW-603, Baierschmidth , Larwick, 

 Sierra, HW-601 and Magness. On the other hand the cultivars Flemish 

 Beauty, Clapp's Favorite, Guyot, Enie, Caspar #5, Krol Sobiensky, 

 Pioneer, Phileson, Soothworth and Luscious were quite resistant to 

 cold injury. Najou, Aurora, Kieffer and Patten were of medium cold 

 hardiness. Of 30 cultivars of plums evaluated only a few seem to 

 be cold resistant. These are Mont Royal, Stanley, Grenville, 

 Kahinta, Damas and Reine Claude. Among the sour cherry cultivars 

 Meteor, Suda Hardy and English Morello seem to be more cold hardy 

 than North Star and Montmorency. 



In general the trees which bore a bumper crop of fruits in 

 1980 proved to be quite tender to cold injury during the winter 

 of 1980-81. The trees which were weak and the ones located in 

 frost pockets or the ones growing in poorly drained areas behaved 

 the same way. Many Mcintosh trees that were girdled (scored) 10 

 days after full bloom in 1980 died during the winter of 1980-81. 

 Almost all the trees which had been pruned in November, December 

 and January died. Severe summer pruning during June and July of 

 1980 created a weak resistance to cold stress. Deer damaged trees 

 in many instances appeared as severely injured by the winter injury 

 as those that were summer pruned. In many cases excessive herbicide 

 applications caused the death of fruit trees. Thus factors that 

 interfered with tree maturity during the summer and fall of 1980 

 had an important bearing on cold tolerance during this last test 

 winter . 



White plastic mouse guards protected the bottom of many trees 

 as well as did a heavy coat of snow. The trees pruned with the 

 new TTS (Tip top shape) pruning method were less injured by cold 

 than others. 



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