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Clover Sickness. 



[JULY, 



Oat plants that are attacked remain short and stunted, 

 the base of the stem is swollen, and the ear does not escape 

 from the sheath. As in the case of " clover sickness " the 

 disease usually commences in isolated patches in different parts 

 of a field. These patches gradually increase in size and 

 encroach on each other, until finally the entire crop is destroyed. 

 A small patch of oats was sown in soil that was sprinkled 

 over with finely cut up clover infected with eelworms, and 

 within nine weeks every oat plant was infected. 



When onions are attacked, which only occurs during the 

 young condition, the base of the stem becomes swollen and 

 the leaves are more or less wrinkled and deformed. Further 

 growth is checked. 



Not infrequently an epidemic caused by eelworms suddenly 

 appears for the first time in a field, or in a district where such 

 disease had not previously occurred. Such unexpected out- 

 breaks are explained when the varied methods by which 

 eelworms may be conveyed from one place to another are 

 taken into consideration. It has been proved that these 

 organisms can pass through the alimentary canal of an animal 

 without injury, hence if a hare or a rabbit eats infected clover 

 the dung may be deposited at a considerable distance from 

 the point where the food was obtained. Again, eelworms 

 in the egg stage can survive a long period of desiccation, and 

 being so very minute are blown from place to place in the 

 form of dust, which on being washed to the ground by rain 

 proves a source of danger. When soil is once infected there 

 is always the danger of conveying the disease to adjoining land 

 by soil adhering to tools, cart wheels, &c. 



The annual loss in this country caused by eelworms is very 

 considerable, but fortunately the remedy against such loss is 

 thoroughly practicable and effective if promptly applied. 



When a crop shows signs of disease, a dressing of sulphate 

 of potash should be applied at once to the diseased patches, 

 taking care to extend the dressing somewhat beyond the 

 obviously diseased plants. 



It may be taken for granted that land that has produced 

 a diseased crop is infected, and as eelworms are able to 

 live in the soil for some years, it is important that such land 

 should be sterilised. This can be done most thoroughly by 



