146 INSECT PESTS 



gular patches of dark olive green on the tops of the 

 leaves. Later on, when these leaves fall, black spores 

 will be formed, and these will disperse and eventually 

 find a home on the bark and fruit, specimens of the latter 

 with the fungus on them being shown. It is only when 

 fruit is bruised and the skin broken that Scab becomes 

 really detrimental, or when it fastens itself on young 

 fruit and retards the growth. The food value of the 

 apple shown in the sketch is scarcely reduced by the 

 Scab, but its market price, at all events in pre-war days, 

 might be seriously altered. Bordeaux on the trees in 

 spring will prevent this disease getting a serious hold. 



The leaf shown on the right wiU be seen to be covered 

 with regular round spots. This is the Apple Leaf Spot 

 {Sphceropsis malorum), a fungus which causes also a brown 

 rot of the fruit. The secret of spore production is shown 

 in the microscopic section of a leaf through the middle 

 of a spot, and as it is magnified about fifty times it will 

 be understood how easily these tiny bodies may be wafted 

 about from place to place. All fallen material should 

 be carefully gathered up and destroyed, whilst Bordeaux 

 mixture should be used where necessary in the spring, 

 just after the petals have dropped. (See Plate 36.) 



The cultivation of field Strawberries is so important 

 in these days that a passing reference must be made of 

 a common injury that the plants suffer in the form of 

 a fungus called SphcBrella fragarice, or Strawberry Leaf 

 Spot, which assumes the aspect shown in the illustration, 

 the colour of the spots being first brown or reddish- 

 brown, and later a white spot appearing in the centre 

 of the ruddy patch. The white spot itself is bounded by 

 a red ring, which gives this disease the popular name of 

 Bird's Eye Spot. The effect of Strawberry Leaf Spot is 

 to materially reduce the yield of fruit and weaken the 

 plants for the following season, but it may be prevented 

 by careful watching and an early spraying with either 

 liver of sulphur or Bordeaux, to be repeated at intervals 



