EXPERIMENTAL STATIONS — TURNIP CROP 1882. 



387 



It is evident that, by the expenditure of £2 per acre, there is 

 no profit, but a loss of £2, for the crop is comparable with 

 that of the plots which received nothing at all. When £3 

 per acre is spent on manure, 6 J tons of turnips are got for it ; 

 that is, an average cost for manure of about Qs. per ton of 

 turnips. When £4 per acre is spent on manure, nearly 12 tons 

 per acre of turnips are got for it, or an average cost of fully 

 6s. 6d. per ton. It is probable that had another 20s. per acre 

 been spent on the manure of these turnips, the average produce 

 would have amounted to from 24 to 25 tons per acre ; that is, 

 about 16^ tons increase for £5 spent on manure, making the 

 cost a little below 6s. 6d. per ton. Any further increase of 

 manure would have produced only a small increase of turnips, 

 if any, and it is evident that we have reached the limit of 

 profitable manuring when we apply one and two-thirds the 

 amount of manure we are putting upon these turnips. That is 

 to say, it would pay best to spend £5 per acre in turnip manure 

 of the kind we are applying for Pumpherston station ; and if it 

 did not pay to spend £5 per acre, it would not pay to grow 

 turnips there at all, for turnips can be grown cheaper at a cost 

 of £5 per acre for the manure we are using, than they can be 

 grown at any less manurial expenditure. 



For every soil and system of manuring, there is a point 

 beyond which it is unprofitable to go in the application of 

 manures, and that is a point short of which it is unprojitahlc to 

 stop. It is as easy to underdo, as it is to overdo the manure 

 expenditure, and the temptation to the former is very great. 

 What that point is every farmer who grows turnips must dis- 

 cover for himself, and an experiment, such as the one here 

 described, is one that should be practised by every farmer in the 

 country. 



