common red clover and turning it in the second year. Clover not only 

 supplies the needed humus, but has the effect of introducing nitrogen into 

 the soil from the air, and since nitrogenous forms of fertilisers are the most 

 expensive, it is so much saved to the orchardist. The best plan is to buy 

 commercial fertilisers separately, that is, not a mixed fertiliser, as the farmer 

 can then apply them in the proportions he wishes. It is, of course, difficult, 

 perhaps impossible, to say what constituents the soil is deficient in; but 

 ordinarily, a fertiliser containing one and one-half to two per cent, of 

 nitrogen, seven to nine per cent, of available phosphoric acid, ten to twelve 

 per cent, of potash, will give excellent results when applied to orchard land 

 in quantity ranging from 400 to 600 pounds per acre, but if a crop of clover 

 lias been turned in the nitrogen can be omitted. Prof. Shutt, in a lecture 

 at the annual meeting of the Nova Scotia Fruit Growers' Association, in 

 February, 1899, thus describes the functions of the three principal elements 

 of plant food, nitrogen, phosphoric acid and potash, viz. : 



" Nitrogen is an essential for plant life. Its function, more particularly, 

 is to promote leaf growth. Leaves are very necessary to the well-being of 

 the tree, as they serve the purpose of both mouth and stomacn. The fruit 

 also contains a certain amount of nitrogen. It is chiefly, however, for the 

 development of the leaf, without which a good crop of well-formed apples is 

 not obtainable. Trees, in common with all plants, take their nitrogen from 

 the soil in the form of nitrates compounds formed by various influences and 

 under certain conditions from the nitrogenous organic (vegetable) matter in 

 the soil. The process is known as nitrification, and is brought about by the 

 agency of minute organisms (always present in the soil) when the soil is in 

 good tilth, warm and moist. 



" Phosphoric acid is contained in the mineral part (ash) of the woody 

 tissue in wood and leaves, as well as in the fruits and seeds. It is not only 

 necessary for growth, but seems to have a special value in the maturation or 

 ripening both of the wood and fruit. 



" Potash : This, of all the mineral constituents, is the most important 

 for fruit trees, both large and small. The well-being of the tree largely 

 depends upon an abundant supply of soil potash in an available condition. 

 It forms by far the greater portion of the ' ash ' of the wood and leaves, and 

 approximately one-half of that of the fruit." 



Lime is not a fertiliser in the strict sense of the term, its functions 

 being chiefly in the liberating of plant food, which is already in the soil but 

 in unavailable forms, and also in the improvement of the conditions of clay 

 and hard, refractory soils. Prof. Shutt says of it: 



" Lime is not so necessary for apple and pear trees as it is for the stone 

 fruits, but it is, nevertheless, a valuable constituent for the orchard soil, for 

 trees grown upon limestone soil are found to be sturdy, strong stock and to 

 have a vigorous growth. Lime acts in two ways, mechanically and chemi- 

 cally. It serves directly In furnishing nourishment for the growth of the 

 tree; it serves indirectly in the liberation of locked-up plant food, more 

 especially of the potash. It does most useful work in improving the texture 

 of both heavy clay and light soils. It is usually, however, on the former 

 that it is especially needed." 



