11 Pkb., 1918.] Diseases of Fruit Trees. 105 



Black Spot or Scab in Apples and Pears. — Spray trees as soon as 

 buds separate from one another, so that the spray can run down the 

 flower stalk, using either Bordeaux Mixture (6.4.50 formula) or Copper 

 Soda Spray (6.8.50 formula — 6 lbs. blue stone, 8 lbs. washing soda, 50 

 gallons water) ; for late or summer spraying, using this at half strength. 



Shot Hole of Stone Fruits. — Spray with Bordeaux Mixture or 

 Copper Soda before flowers open. Spraying as soon as leaves have 

 fallen is advised for trees that have suffered badly from attacks of this 

 disease. 



Peach Curl. — Spray with Bordeaux Mixture as soon as buds swell 

 in spring, and just before the leaf buds burst. A spraying with blue- 

 stone (1 lb. in 25 gallons of water) has given good results when imme- 

 diately followed by an oil apray at strength of 1 in 25. 



Shot Hole of A pricot. — Spray with Bordeaux Mixture or Copper 

 Soda spray when the buds ai'e showing pink. 



Armillaria. — This is a root-killing fungus, and is very destructive 

 to trees in certain soils, such as some of the red and sandy soils that 

 have a cement sub-surface, especially on land that has not been 

 thoroughly cleaned of roots of native trees previous to planting. Several 

 remedies are recommended for coping with this disease, among which 

 Sulphate of Iron, Bordeaux Mixture, and Bordeaux Paste are the prin- 

 cipal. One thing that should be borne in mind is that summer treat- 

 ment is likely to prove dangerous to the tree. Bordeaux Paste is 

 applied after baring the roots, which, if done in hot summer weather, 

 must be injurious to the tree. Again, if drenching with a fungicide to 

 the soil sufficient to reach the disease on the roots is given in hot weather, 

 when the roots are in a most active condition due to the rapid transpira- 

 tion of water by the leaves, trouble is likely to result, and probably the 

 tree will die. The best time to make root applications is during the 

 winter months, or after heavy rains in autumn. 



Bordeaux Paste is made as follows: — 



Sulphate of Copper (Bluestone), 1| lbs. 

 Quicklime, 1 lb. 

 Water, 2 gallons. 



Remove soil and apply to roots with a brush. 



Bordeaux Mixture, 6.4.50, sprayed on roots. 



Sulphate of Iron, 1 lb. in 4 gallons of water, sprayed on roots. 



In preparing Bordeaux Mixture three vessels are used, preferably 

 of wood (iron vessels must on no account be used in its preparation). 

 Formula, Bluestone, 6 lbs. ; Quicklime, 4 lbs. ; Water, 50 gallons. Dis- 

 solve the bluestone in a barrel with 25 gallons of water, and in another 

 barrel slake the lime and make 25 gallons of lime-water. These two lots 

 of 25 gallons should be poured evenly into a third vessel, keeping it 

 well stirred at the same time. A test can be made on this mixture by 

 inserting a clean knife-blade into it for a minute or two ; if the steel 

 bronzes it shows the presence of free copper in the solution', and a little 

 more lime should be added until the knife-blade shows clean. In bad 

 seasons, it may be of advantage to lessen the water to 40 gallons, both 

 in the Bordeaux Mixture as well as in the Copper Soda spray. In the 

 preparation of the latter spray, the same method is adopted as in the 

 Bordeaux, only tiie washing soda takes the place of lime. In the pre- 

 paration of any spray, good, soft water should be used. Bordeaux 



