10 May, 1919.] Apple Culture in Victoria. 289 



If the ingredients in the Bordeaux be of good quality, ])roperly 

 mixed, and in relation to strength a.s judiciously applied as is necessary 

 in the case of lime-sulphur, the writer's experience is that vorv little 

 damage follows its application, even after the fruit has set. 



The following extract is taken from an article* written b_y W. 

 Laidlaw, B.Sc, Biologist, and C. (•. Brittlebank, Vegetable Pathologist, 

 concerning their spraying experiments for ''black spot" in the Gipps- 

 land district: — 



"Experiments in the treatment of black spot were made on six 

 different varieties, all of w^liich are commionly grown throughout 

 the State. 



The disease was very ]irevalent in the orchard where the experi- 

 ments were conducted, in wet years the bulk of the apple crop 

 being so badly affected as to be unsaleable. 



The past season's rainfall was above the average at Drouin. The 

 spraying season — September and October — was exceptionally wet. 

 During these months there were 43 wet days and 11^ inches of 

 rain fell. I^otwithstanding this excessive rainfall, the experiments 

 were very successful, as will be seen by the results. 



Last season we confined our experiments to the lime-sulphur 

 ■spray principally, using the commercial product. Three different 

 brands were used, and each gave equally good results. The cost 

 of m'aterial works out at 3d. per tree. 



The dates on which the different varieties were sprayed are 

 given below, not as a guide, but as showing the time when the buds 

 were more green than pink, vp'hich was the condition of the trees 

 when the first spray was applied. The second spray "w^as given 

 when the centre flowers of the blossom cliLSter were fully open. 



We are of opinion that the time of spraying is more important 

 than the fungicide used, provided the mixtures are properly made 

 and tested. Wliile making this statement, we must point out that 

 the result obtained from lime-sulphur last season was very much 

 better than that obtained from Bordeaux, 6-4-40. The foliage 

 looked healthier, and remained longer on the trees; the skin of 

 the fruit had a better colour, and was clearer and sappier looking. 



We would like to impress on growers the necessity of having all 

 the cultivation done before spraying is commenced. The reason 

 for this is that the resting spores have developed in the fallen 

 diseased leaves of the previous season, reaching niiaturity at the 

 time the apple trees are coming into blossom. 



Under favorable weather conditions, they are thrown out' in 

 countless numbers, and are carried by air currents into the young 

 leaves and fruits, where they germinate and infect the crop. Cul- 

 tivation should not be resumed till all danger of infection is past. 

 This period will vary in different districts and under different 

 Aveather conditions. 



* Published in Join-nal of Agrirulture (Victoria), August, 1918. 

 5110.— 2 



