Scientific Agriculture. 54 [July, 1012. 



or whisky, tea made by pouring boiling stand* do not let it lie on one side for 



water on to lucerne hay and allowing it long, turn it over or prop it up with 



to cool, etc., and either move the animal sacks filled with sand, and do not take 



into the shade or build a temporary the advice of ten people at once— try one 



shelter of sacks over it; if unable to at a time. 



SCIENTIFIC AGRICULTURE. 



THE PHOSPHATE NUTRITION OP 

 PLANTS, 



By Allan Baguley, 

 (From the Journal of Agricultural 

 Science, Vol. IV., Pt. 3, pp. 313-322+ 

 fig. 1, Cambridge, January, 1912.) 



(Bulletin of the Bureau of Agricultural 

 Intelligence and of Plant-Diseases. 

 3rd Year— Number 4, April, 1912.) 



Much work has been done in America, 

 on the Continent and in England, to 

 determine the effect of different finely- 

 ground, naturally-occurring phosphatic 

 substances on plants growing under 

 different conditions. In a few cases 

 results or conclusions appear to conflict. 



Not nearly so much attention has been 

 devoted to the effect of artificially pre- 

 pared insoluble salts of phosphoiic acid 

 on the growth of plants, when these are 

 employed in the absence of ammonium 

 salts, and acid soil substances. Definite 

 information should be obtained as to the 

 powers possessed by plants of utilizing 

 insoluble phosphates. 



For this purpose, the writer made 

 pot cultures of peas, oats and swede 

 turnips. The medium in which the 

 plants were grown was chiefly made up 

 of pure white sand ; to this were added 

 the different phosphates, and a nutrient 

 solution. The phosphates used were 

 ferric phosphate, aluminium phosphate, 

 and calcium phosphate. Grown with 



calcium phosphate, oats germinated and 

 died ; peas developed badly with few 

 flowers and puny pods ripening early , 

 the swedes commenced to grow about 

 six weeks late, but developed normally. 



Grown with ferric phosphate, oats 

 made strong very well developed plants 

 with dark foliage, and plenty of seed 

 ripening late ; peas made sturdy healthy 

 plants with well-developed pods, not 

 very numerous, ripening late ; swedes 

 grew steadily and well from the start. 

 The results obtained with aluminium 

 phosphate were much the same. 



Compared with the superphosphate 

 plants, the oats did not tiller so well as 

 these latter, but they were in each case 

 clearly stronger in the straw and longer 

 in the ear, being finer plants altogether ; 

 the swedes were both larger and more 

 healthy than with the superphosphates ; 

 the peas grown with ferric phosphate 

 and with aluminium phosphate were 

 neither so early nor so fruitful as when 

 grown with superphosphate. 



With calcium phosphate the results 

 were very different : the oat plants were 

 very ill-developed and produced no ear 

 at all: the swedes started badly, but at 

 the end of the season, though late, were 

 healthy plants; the peas grew modera- 

 tely well, but the plants ripened early 

 and the crop was poor. 



Subsequent experiments were carried 

 out with the object of ascertaining the 

 effect of ignition and extraction with 

 boiling water on the availability of the 

 precipitated phosphates. The results 

 showed that ; 



