PERMANENT PASTURES. 393 



tained practically free from weed seeds would be great- 

 ly serviceable for such dressings. Muck from swamps 

 and peat from bogs, when the latter is sufficiently de- 

 cayed are also helpful on certain soils; the same is 

 true of the material from compost heaps, of marls, lime 

 and gypsum. When applying these dressings, the cost 

 of the labor and the distance to which they need to be 

 drawn must be carefully considered. Light dressings 

 and frequent are to be preferred to heavy and infre- 

 quent dressings, as in the former instances there is less 

 loss through fertility being carried away by excess of 

 water. 



After the pastures are laid down, commercial fer- 

 tilizers can of course be only applied on the surface. 

 By whatever name these may be known in the market 

 the important food elements in them for the grasses are 

 not morfi than three, viz., nitrogen, phosphoric acid and 

 potash. The first is more commonly applied in the 

 form of nitrate of soda, sulphate of ammonia or flesh 

 meal from slaughter houses and it is helpful in promot- 

 ing growth in grasses and clovers. The second is used 

 in such forms as ground bone, ground rock containing 

 phosphates and basic slag and is especially helpful to 

 the grasses. The third is used in such forms as muri- 

 ate and sulphate of potash, kainit and wood ashes, and, 

 although quite helpful to both grasses and clovers, it 

 tends more to stimulate growth in the latter. 



Whether one or two or all three of these shall be 

 applied as top dressings; the quantities of each that 

 shall be used and the frequency of the dressings must 

 be determined by the needs of the soil. In some in- 



