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hoofs and horns, skin clippings, waste feathers, rape dust, and the like 

 they comparatively rarely applied phosphates, except in the form of 

 fish guano, rape cake, and purchased dung, in which manures phos- 

 phates may be considered as existing in quite insufficient proportion 

 to form a practical balance to the nitrogen present. The application 

 of potash, too, was neglected in a great number of gardens where it 

 might have done good. 



These mistakes are now being generally recognised. Professor 

 HALL, the late Principal of Wye College, and present Director of the 

 Rothamsted Agricultural Experiment Station, in a summary which he 

 has recently written of the hop manuring experiments carried out 

 under his auspices, points out that the general conclusion so far 

 arrived at is " that the hop plant is one which shows no special re- 

 quirements in one direction or another, but is an all round feeder. " 

 It is not comparable with the Swede, |" which shows a special depen- 

 dence on a free supply of phosphates," or with potatoes, "which 

 particularly need plenty of potash." The hop " requires what may 

 be termed a normal mixture of all the elements of plant food." 



Doubtless many soils on which hops are grown are of great 

 natural fertility and rich in mineral plant food ; and even to-day there 

 are, no doubt, soils independent of any special application of phos- 

 phates or potash or both. But there must be a great many gardens 

 the mineral resources of which have been too heavily taxed in the past 

 by almost exclusive nitrogenous manuring. 



It is also to be remembered that the average crops grown to-day 

 are usually greatly in excess of those grown in, earlier times. This is 

 no doubt attributable to improved general knowledge on the subject of 

 the prevention and mitigation of the ravages of the green fly, red 

 spider and mildew, and to the availability of improved appliances, for 

 coping with these pests. Obviously an increased output should be 

 accompanied by increased manuring, if the productivity of the soil is 

 to be maintained. 



Although the Wye College experiments, to which allusion has 

 already been made, show that different soils vary in their mineral 

 requirements in relation to hop growing, and that probably in no 



