160 



Examples of potash fertilizers are: Sulphate of potash and 

 muriate of potash. Those of phosphatic fertilizers : Superphos- 

 phate, basic slag, and bonedust, the last named also supplying a 

 little nitrogen, while sulphate of ammonia and nitrate of soda 

 may be cited as examples of nitrogenous fertilizers. 



Supposing a fruit-grower is desirous of ascertaining whether 

 fruit trees on his land will respond to potash, all he need do is to 

 apply phosphatic and nitrogenous fertilizer to a number of trees 

 and make a note of it. Such a dressing is known as an incom- 

 plete fertilizer, as it does not supply all the three important plant 

 food ingredients. To an equal number of trees of the same age, 

 variety and size, on similar land, he should apply the same 

 amounts of phosphatic and nitrogenous fertilizer, plus, say, 1 to 

 2 lb. sulphate of potash per tree. 



Similarly, if a grower desires to find out if it will be profitable 

 to apply phosphatic or nitrogenous fertilizer, he may proceed on 

 similar lines, omitting the particular fertilizer which he needs 

 the information about from the dressing, in one case, be it phos- 

 phatic or nitrogenous, and including it in another. In this way 

 the fruit-grower may observe the behavior of the trees towards 

 the particular kinds of fertilizers. 



Fruit crops are unlike most farm crops, in that the effects of 

 fertilizers are not so readily observable, and the beginner needs 

 to be warned against expecting outstanding results the first sea- 

 son. The second and subsequent seasons, however, good results 

 may follow rational manuring. 



Mr. Alfred Thiessen of Geeveston, Tasmania, laid down ex- 

 periments on the three-plot system in the spring of 1912 with 

 ai)ple trees. The trees on the No. 1 plot were left unmanured, 

 those on No. 2 received 3 lb. superphosphate, 2 lb. bonedust, 3^ lb. 

 sulphate of ammonia, 1^/4 lb. sulphate of potash per tree, and 

 those on No. 3 received 3 lb. superphosphate, 2 lb. bonedust. 

 y2 lb. sulphate of ammonia. 



The yields, calculated jkt acre, for the first season were : Plot 

 1, 560 cases; Plot 2, 800 cases; Plot 3, 666 2/3 cases. 



The past season's results (being the second year of experi- 

 ment) were: Plot 1, 524^. cases ;>lot 2, 1022J4 cases; Plot 3, 

 915 cases. 



The absence of fertilizer on Plot 1 accounted for considerably 

 lower yields. The trees on Plots 2 and 3 each received the same 

 amounts of superphosi)hate, bonedust and sulphate of ammonia. 

 Those on Plot 2 were given Ij/^ lb. sulphate of i)otash in addition. 



The difference in yield, and conse(|uently the money value, 

 between the two plots was well marked, and showed that the 

 cf)mj)lete fertilizer was the most profitable one. — The Fruit IVorld. 



