846 EXPERIMENTAL FARMS 



5 GEORGE v., A. 1915 



warm moist weather following the midsummer drought and the occurrence of this 

 Jate infection in orchards that had been well sprayed raises the question as to whether 

 an additional summer spraying will not be necessary in seasons like the recent one. 

 According to the best orchard practice at present, three sprayings are given with com- 

 mercial or home-boiled lime-sulphur, the first being applied just before the blossoms 

 burst, and should test with the hydrometer 1-030 specific gravity; the second (testing 

 1-009) is applied just before the blossoms open; the third (testing 1-008) is put on 

 just after the blossoms fall, but while the calyces still remain open. The fourth 

 application which may he necessary in damp summers should be given as soon as 

 indications of the scab appear on leaves, where it usually first shows itself. 



Black Rot (Sphceropsis malorum Pk.). — This fungus is responsible for the greater 

 part of our apple rot, especially on fallen fruit. In our climate it is most seriously 

 prevalent in the fruit on the tree, but it attacks windfalls and apples in storage. It is 

 far less prevalent in well pruned and sprayed orchards, and a great deal can be done 

 to lessen the infection of the fruit by keeping the trees free from fungus. Infec- 

 tion takes place from spores derived from old rotten fruit and also from spores formed 

 in cankers, sun scald areas, and dead twigs. If care is taken in priming to remove 

 these sources of infection as far as possible, and to destroy fallen fruit, the effects 

 of Black Rot on the fruit will be materially lessened. 



Sun Scald. — Frequent cases of this form of injury are met with. It is sometimes 

 seen on apple trunks, but may also be found on the larger limbs. Sun scald often 

 follows an attempt to put an old neglected orchard into bearing condition. The trees 

 are cut off so as to take away all the limbs above convenient spraying and picking 

 height, and if this pruning is injudiciously done many of the large limbs are left 

 exposed. In early spring the upper sides of these limbs are heated by the hot midday 

 sun, and eitlier because of frost which follows at night or because of inability to ob- 

 tain water from the still frozen soil theses- exposed areas are killed. The liability to 

 scald may be greatly lessened by a coat of whitewash applied to the trunk and limbs. 

 This reflects the heat from the surface and thus avoids exposure to extremes of 

 temperature. 



Collar Rot is another form of injury to apt)le, pear, plum- and peach tree, 

 brought about by winter conditions. The loss due to it from year to year is far more 

 than is generally recognized, and it is apt to occur on trees just when they should 

 have a long bearing period before them. Late cultivation which retards ripening of 

 the tissues is conducive to the trouble, and it is worst in wet undrained soils, soils 

 lacking in humus, and those which are hard and earthy. Mulches of straw and ma- 

 nure or even soil give a protection against collar rot. Whiile numerous cases of collar 

 rot have been met with in apples, pears also suffer considerably, and Japanese plums 

 are quite susceptible to it under the conditions mentioned. 



PEAR. 



Pear Blight {Bacillus amylovoru^ De Toni). — 'This disease has made such 

 serious inroads to the pear orchards of the Niagara peninsula that many of 

 thei. more susceptible varieties have been given up as a profitable crop, and 

 the entire acreage of pears has been greatly reduced in spite of the uniformly good 

 prices that this fruit brings. The disease varies in virulence from year to year ac- 

 cording to weather conditions which greatly affect its spread, and it is also worse in 

 some districts than in others. In the recent summer the St. Catharines region had 

 little or none, while quite a few orchards at Beamsville, Grimsby, and Stoney Creek 

 were badly attacked. Control measures involve rigorously cutting out all parts af- 

 fected by blight as soon as it appears, and it is especially advisable to go over the trees 



Ottawa. 



