-15- 



It was the scion cultivars which were hit by cold and not 

 the rootstocks. However, many apple trees on M. robusta 5 

 rootstock died this year with those 10 to 15 years of age parti- 

 cularly affected. Trees over 20 years of age on M. robusta 5 

 were not damaged. It looks as if the young M. robusta trees which 

 started to come into bearing were more susceptible to low temper- 

 atures in late winter or early spring. 



The most affected areas in the province were those located 

 along the U.S. Border and the Two Mountains region. The Rouville 

 region proved to be somewhat less vulnerable to winter injury. 

 The Lower St-Lawrence region (below Quebec City) suffered the 

 least from the 1980-81 winter. The presence of a large body of 

 water, the more abundant snow precipitation and the late blooming 

 season of that location are certainly the prevailing factors which 

 may explain the better performance of the fruit trees (apple, 

 plum, pear, cherry) in this area. 



The cultivar Lobo sustained the least winter injury in all 

 regions of the province. Along with Lobo some other cultivars 

 such as Melba, Jersey Mac, Wealthy, Jonamac, Melred, Yellow Trans- 

 parent, Vista Bella and Paulared proved to be cold resistant. 

 However, cultivars such as Mutsu, Red Delicious, Golden Delicious, 

 Northern Spy, Rhode Island Greening and Golden Russet were classed 

 as those most sensitive to winter injury. Cultivars such as Mcintosh, 

 Cortland, Idared, Empire, Spencer, Spartan and Red Haralson fell 

 into the medium class of resistance to cold injury. 



Needless to mention, having experienced such a severe winter 

 this year's apple crop is greatly reduced. Our average production 

 for the past 5 years has been 5.3 million bushels. This year's 

 crop will most likely fall between 2 or 3.5 million bushels. 

 Because of the late spring frosts there also will be a larger 

 percentage of culls (misshapen fruit) this year. Since the trees 

 are weaker than normal there also is a fairly large quantity of 

 apples that were attacked by diseases and insects. 



Special attention had to be given to the cold injured trees 

 during the summer of 1981. Dead limbs were removed to prevent 

 the development of cankers. Painting large pruning wounds or tree 

 crevasses with Bordeau paint appears to have proven very effective. 

 This paint consists of a mixture of 2 pounds of monohydrated copper 

 sulfate or fixed copper (c.o.c.s., etc.), 4 pounds of hydrated lime 

 and two parts of boiled linseed oil. It is important to mix the 

 two powders first and then add the oil. Otherwise the mixture will 

 not be uniform. Moreover the Bordeau paint dries very rapidly. It 

 will harden within 6 hours if exposed to air. Since it is a paste- 

 like mixture it could be easily applied with a brush. Other coat- 

 ings such as interior white latex paint plus mercuric bichloride 

 or plus a fungicide such as sulphur or Thiram have been used and 

 seem to have served the purpose. In several cases a special tree 



