48 EXPEBIMENTS "WITH EEFEEENCE TO THE POTATO DISEASE. 



outside row pi'oduced at the rate of 20 tons per acre of sound 

 tubers, the proportion diseased was nearly II per cent, less than 

 in the rows acljoining, to which nothing was applied. In the 

 rows Nos. 2 and 3 the per centage of diseased tubers was above 

 the average. 



The rows 4, 5, 6 had nothing applied. Their produce was 

 diseased to the extent of 24 per cent. ; still, the quantity of 

 sound tubers amounted to 11 tons 3 cwt. 70 lbs., which is a fair 

 crop. 



Salt, Lime, and Charcoal. — The results are given, Nos. 7, 

 8, 9, Table I. The quantities employed were, salt 3 lbs., lime 



I bushel, and charcoal, powdered, -^-^ bushel to 3 rows, or 5 cwt. 

 23 lbs. salt per acre, the quantities of lime and charcoal being 

 the same as were employed for the rows 1, 2, 3, and applied 

 in the same way ; but tlie salt was scattered over the ground 

 previously to cutting out the drills for tlie sets, in order that 

 it miglit be mixed with the soil ; in fact, this experiment dif- 

 fered only from the first as regards the salt ; and it appears by 

 the results Nos. 7, 8, 9, and their average, that the salt had not 

 proved a beneficial addition. In the beginning of July it was 

 observed that in these three rows the stems and foliage were of 

 a paler green than in those adjoining. The average produce of 

 sound tubers was at the rate of 10 tons 9 cwt. 33 lbs., being less 

 by 2 tons 3 cwt. 22 lbs. than the average of sound produce in 

 the rows to which nothing was applied. The portion diseased 

 was 4 per cent, above the average, and 5 per cent, in excess of 

 that where oidy lime and charcoal were employed. 



To row 10 nothing was applied. The total produce was at 

 the rate of 22 tons 15 cwt. 85 lbs. per acre, of which 17 tons 

 10 cwt. 105 lbs. was the proportion sound, nearly one-third 

 above the average. 



Young tubers of the Ash-leaved Kidney were planted in rows 



II and 12. Hot weather and the excitability induced by the 

 disease occasioned premature vegetation in many of the tubers 

 produced by plants of early potatoes grown in the kitchen 

 garden in the summer of 1846. Instead of remaining dormant 

 till the following spring, they pushed stems above ground the 

 same autumn. Some of these young plants were taken up 

 before frost and planted in a frame, wliere they formed tubers 

 early in 1847 ; but these were of an imperfect character, evincing 

 a strong disposition to send out runners, as is the case with some 

 wild potatoes. Disease likewise appeared amongst them at an early 

 stage of their growth. They were then taken up, and the sound- 

 est exposed to light till the time of planting in the open ground. 

 The two rows 11 and 12 were planted with these tubers, a gene- 

 ration younger than those usually planted. Many of them failed 



