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Finger- an d-Toe in Turnips. 



for example, as potato disease. It does, however, readily spread 

 from the first point of attack in various ways. For instance, it 

 may be borne in soil which sticks to the plough, to the wheels ot 



Specimen of Turnip {slightly reduced in size) in advanced stage of attack by 

 Finger-and- Toe. 



carts or other agricultural implements, or to the feet of workers, 

 horses, or sheep. Suppose that a small patch of turnips in a 

 large field is affected by finger-and-toe, a certain amount of soil 

 will be borne from this patch and dropped elsewhere on the field 

 every time a plough, harrow, cultivator, or scuffler crosses it, and 

 wherever such soil is dropped a new centre of infection is 



