THE FARMER'S MAGAZINE. 



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given the amount of mineral matter contained in 

 one ton of tbe entire plants, bulbs and tops, of the 

 common turnip. It is as follows : — 



The amount of the mineral and organic matters 

 of the turnip plant varies, however, in different 

 seasons and climates. This fact has been to some 

 extent ascertained by Professor Anderson and Mr. 

 J. B. Lawes. The Professor examined the compo- 

 sition of turnips grown in the same season from the 

 same seed, in Argyleshire and in Warwickshire 

 {Trans. High. Soc, 1856, p. 420); and although 

 his trials are by no means conclusive in them- 

 selves, yet they well serve to indicate the import- 

 ance of continued experiments. They illustrate, 

 remarks the Professor, one of the great difficulties 

 with which we have to contend in such inquiries, 

 for we know nothing precise regarding the climate 

 of these counties, further than that Argyleshire is 

 characterized by the abundance of rain during the 

 summer and autumn months, and by a low sum- 

 mer temperature ; while Warwickshire has as 

 favourable a chmate as any Enghsh county. The 

 turnips analyzed were swedes and yellows, both 

 grown from the same seed in each locality, and 

 treated in a precisely similar manner. The follow- 

 ing were the results per cent. ; — 



Comparing these analyses, adds the Professor, 

 it is at once seen that the turnips grown in War- 

 wickshire materially exceed in value those from 

 Argyleshire. The swedes from Argyleshire con- 

 tain 2 per cent, more water than the Warwickshire 

 swedes; 10,000 parts of the Warwickshire swedes 

 contain 661 parts of solid matters, while the same 



quantity of those from Argyle contain only 440. 

 If we assume the amount of solid matters as the 

 measure of the nutritive value of the two samples, 

 then it would follow that two tons of the War- 

 wickshire swedes must be equal to nearly three 

 tons of the Argyleshire, and it is probable that this 

 is not far from the truth. 



The trials of Mr. Lawes were carried on in his 

 usually extensive and elaborate manner, at Rotham- 

 sted, in Hertfordshire, and were chiefly directed to 

 the question of the influence of the amount of rain- 

 fall, and the mean temperature of the turnip sea- 

 son, upon the produce of the crop. In his trials in 

 the years 1844 and 1845, he obtained the following 

 results :— 



The mean temperature from June to 



end of Oct. — turnip season 



No. of days on which rain fell during 



this season 



Inches of rain falling . . 



Produce of bulbs per acre in tons and 

 cwts. : 

 Manured with 12 tons of farmyard 



dung 



Do. with superphosphate of lime 



1844. 



59.4 



67 

 10.37 



1845. 



57.8 



74 

 9.62 



714 



10 15 

 7 14 12 13 



As a general fact, it is evident, concludes Mr. 

 Lawes, that the amount of the produce of the 

 turnip is very materially dependent upon the 

 climatic character of the season, not only as in 

 itself a resource, but as an essential agent in the 

 appropriative power of the plant, however liberal 

 and complete may be the supply of constituents 

 within the soil. 



To promote the growth of the turnip crop by 

 supplying its mineral and organic substances, two 

 valuable manures — guano and superphosphate of 

 lime — have been extensively used, and with very 

 remarkable success. The employment of these 

 powerful fertilizers, however, has been found to 

 require considerable care in their application to the 

 soil, and moreover that the result of the trial is 

 materially influenced by different chmates and 

 soils. On the fine loamy barley lands of Surrey 

 resting upon the chalk, a mixture of these two 

 manures is commonly used — say, 1 cwt. of guano 

 and 3 cwt. of superphosphate of lime per acre. 

 This proportion of the superphosphate emjjloyed 

 has been gradually increasing for the last two or 

 three season.-;. We have found, in fact, that in my 

 neighbourhood better crops arc thus produced, 

 and moreover that the good eff'ects of the super- 

 phosphate of lime, applied as a dressing to a root 

 crop, are commonly very plainly discernible in the 

 succeeding barley crop, and not unfrequently even 

 in the third or clover crop. It is a common and a 

 good practice with my neighbours, in Surrey, to 

 drill these manures, cither by separate coulters 



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