272 PRINCIPLES OF GARDENING. [CH. VIII. 



Francis Constable, Esq., of Burton Constable, 

 had a field that had been in grass twenty years : 

 this he pared, burned, and sowed ^vith turnips, 

 obtaining a crop perfectly free from the disease. 

 Two white crops were then taken, after which 

 turnips were again sown ; and a considerable portion 

 of the crop was then infected ^. 



I have myself tried the efficacy of common salt 

 in preventing the occurrence of this disease. Its 

 tendency to keep the soil moist, and to irritate the 

 animal frame, certainly checks the inroads of the 

 weevil, and its generally beneficial effects as a 

 manure enables the plants better to sustain them- 

 selves under the weakening influence of the disease ; 

 but it is not a decisive preventive. The following 

 results of one of my experiments was read to the Hor- 

 ticultural Society of London, October 16, 1821 : — 



*' Some cauliflowers were planted in a light sili- 

 ceous soil, which had pre\dously been manured with 

 well putrefied stable maniu'e ; and over one-third of 

 the allotted space was sown salt, at the rate of twenty 

 bushels per acre ; immediately before the planting, 

 in the beginning of July, 1821, the previous crop 

 had been brocoli ; fifty-four plants were set on the 

 two-thirds unsalted, and twenty-six on the one-third 

 salted ; the result has been, that of the fifty-four un- 



^ Spence's Observations on the Disease in Turnips, tenned in 

 Holdemess, " Fingers and Toes." 



