THE MANURING OF MARKET-GARDES CROPS. 1025 



of nearly 2^ tons per acre over the first five years, and nearly 3 tons per 

 acre over the last three years. 



The effect of potash is even greater on the tops than on the roots, as 

 will be seen from the following short table :— 



JERUSALEM ARTICHOKES (TOPS ONLY). 



Average yield of tops 

 per acre over five years 



tons cwt. 



Without Potash 6 8 



With Potash I 9 9 



This has been evident every year, though it is only during the last 

 five years that we have actually weighed the tops as well as the roots. 

 The difference is worth recording in view of the fact that in some countries 

 Jerusalem Artichokes are largely grown as a fodder crop for the sake of 

 the green tops, quite apart from the value of the roots. It is evident 

 that this crop makes a heavy demand on the potash of the soil as well as 

 on other manurial constituents. 



Carrots. 



Carrots we have grown every year but one, but we have eliminated 

 from our records the results obtained in our first year — 1894 — for the reason 

 that the plants were not " singled out " in such a way as to leave a like 

 number of roots on each plot, with the result that the produce of the 

 different plots was not fairly comparable. 



In 1895, 1896, and 1897 we grew good experimental crops, and also 

 in 1899 and 1900. In 1898 alone we failed, owing to drought, to get a 

 sufficiently regular plant for experimental purposes, and the plant was 

 therefore dug up. 



Our custom in manuring Carrots has been to apply no dung directly 

 to this crop, but to grow them after a crop for which dung has been 

 applied. This is in accord with farm practice. We have really set 

 ourselves to answer the question whether, when Carrots are grown after 

 a dunged crop but without receiving dung themselves, it is economical or 

 not to treat them with chemical fertilisers ; and, if so, what are the best 

 dressings to use. 



It will be seen that chemical fertilisers have proved to be of very great 

 value, and that both nitrate of soda and potash salts, in conjunction with 

 phosphates, have produced great and economical effects when applied to 

 this crop. 



We have also each year included plots to which no dung has been 

 applied at any time during the progress of the experiments. 



The variety of Carrots which we have grown has usually been of the 

 " intermediate " or " stump-rooted " type. 



The following table shows the average crops produced on some of our 

 plots during six seasons, and also the average results obtained during the 



Q 



