^<o The Potato. 



''hoeinr/" and ''''earthing ?<p," tliereh/ cutting off the minute tubers 

 tmderneath the surface, which no care of the master can avert, 

 that renders this method so unproductive. 



The third method is a modification of the two preceding. 

 The sets are planted in rows singly, and the rows are kept just 

 the same distance apart ; but the earth is harrowed over with a 

 fine harrow as soon as the sets are clearly distinjjuishable in the 

 rows, and so left. This method is usually practised in ground 

 that has been carefully cleaned, and is far more productive than 

 the second. As it is, however, the interest of tlie proprietor to 

 have his ground, when abandoned by the "potato merchant," left 

 clean as well as manured, the second system only finds favour in 

 his eyes, and is fast superseding the other two. 



We will next examine how long the same potatoes can be 

 grown successfully in the same ground. It has been averred that 

 the potato soon wears out, and that a renewal of both seed and 

 soil is essential to its well-doing. 



In September, 1819, through the kindness of a friend, I obtained 

 from Mr. Prettyjohn, near Kingsbridge, two bags of " golden 

 pink eyes " potatoes. They were immediately planted between 

 the rows of young apple-trees, standing at 5 feet apart, in two 

 lines 18 inches apart from each other, and the same distance set 

 from set, in a nursery of little more than half an acre in extent. 

 And there they remained for twenty-six years (1819 to 1845); 

 growing well and producing abundantly ; yielding from 20 to 25 

 bags per annum, besides those wiiicli, in digging, were planted 

 again for the next year's crop. 



They were manured with about 16 cartloads of stable manure 

 and 4 hogsheads of lime per annum ; were usually dug up in the 

 early part of August, and planted again immediately ; and 

 until 1845 were free from any disease. In the autumn of that 

 year the nursery was destroyed, and numbers of the tubers were 

 found to be diseased. 



Now, in the last week in July, 1845, standing on an emi- 

 nence on the north-east, and looking southwardly over a long 

 orchard of 4 acres in extent, of wliich the nursery before alluded 

 to formed the southern extremity, I was surprised at seeing a 

 broad band of blackened leaves running diagonally across the 

 orchard, bearing the direction of south-west to north-east, 

 and in which band the apple-trees looked as if they had been 

 scorched by fire. Within the lines of the band there did not 

 appear to be a green leaf; the smell was foetid and very dis- 

 gusting. Passing downwards by the road fence to make a closer 

 investigation, I found that the band of blackened leaves was 

 about 1000 feet wide, resolvable into three, like stripes on a 

 ribbon : of considerable intensity in the middle, shading out at 



