1906.] 



Bean Pod Canker. 



411 



top dressing is not altogether correct. If applied in warm 

 months, in May to oats and barley and in June and July to 

 roots, its effect is usually small, but if applied in February to 

 winter crops its action in many cases — perhaps as a rule — is 

 satisfactory. 



This fertiliser cannot be used with equal advantage for all 

 crops. It acts badly as a rule on roots. The best and most 

 certain results may probably be obtained by broadcasting in 

 the spring on rye or wheat. A slight yellowing of the 

 vegetation may result, but this usually disappears, and the 

 effect approximates to that of sulphate of ammonia. 



The pods of scarlet runners and French beans suffer most in 

 this country from the attacks of this parasite. In America it is 

 said to be parasitic on the living rind of 

 ^Canker^ cucumbers, vegetable marrov/s, water- 

 melons and musk-melons. 



On the pods the first indication of the disease is the appear- 

 ance of scattered small dark-coloured specks surrounded by a 

 reddish line. These spots gradually increase in size, and often 

 run into each other, forming irregularly-shaped patches which 

 become sunk below the general level of the surface. In due 

 course the sunken brown patches become more or less covered 

 with a thin whitish crust, consisting of a dense mass of spores 

 or reproductive bodies of the fungus. When mature these 

 spores are carried by rain, insects, &c., and infect neighbouring 

 plants. 



Pods that are attacked when quite young often become 

 variously bent and contorted. The parasite often passes quite 

 through the pod and attacks the beans. If such infected beans 

 are used for seed the crop shows the disease at an early stage of 

 growth, and is killed before the flowering season is reached. 



Although the appearance of the disease on the pods is 

 accepted as the first evidence of its existence by the gardener, 

 nevertheless it usually appears first on the stem, where it forms 

 brownish sunken patches. If such patches are confined to one 

 side of the stem the plant is not killed outright, and the injury 



