MISCELLANEOUS FERTILIZER MATERIALS 99 



to what would take place in the soil, when the compost is kept 

 thoroughly moist. Before applying any of the compost to the 

 land it should be well mixed to make it uniform. The earth 

 is used in layers to absorb the ammonia that may be set free in 

 the process of decay of the organic materials. The amount of 

 fertilizing material obtained from a compost will be equal to the 

 amount of fertilizer material added to it, provided there is no 

 loss; but the availability of these materials will be greater. 



Seaweed. — In states bordering on the ocean seaweed is used 

 a great deal for fertilizer. Stormy weather throws considerable 

 quantities on the beach and the states of Rhode Island, New Jer- 

 sey, New Hampshire, and Massachusetts have used this fertilizer 

 for many years. 



The best way to apply seaweed is in the fresh state. The differ- 

 ent varieties of seaweed contain from 70 to over 80 per cent, of 

 moisture and when it is to be transported any considerable dis- 

 tance it may be spread thin and sun-drie.d to avoid carting so 

 much water. They contain from 0.25 to 1.25 per cent, of ni- 

 trogen, about 0.20 per cent, of phosphoric acid and 0.60 to 1.4 

 per cent, of potash. About 20 to 25 per cent, of the ash of sea- 

 weeds is chlorine.* 



Marl. — There are two principal classes of marls, namely shell 

 marls and green sand marls. The shell marls contain less phos- 

 phoric acid and potash and more lime than the other marls. 

 Marls average about 0.40 per cent, of phosphoric acid and 1.40 

 per cent, of potash. Marls improve the physical condition of 

 some soils.* 



Peat and Muck. — In low wet places where vegetable matter 

 accumulates, decomposition sets in and the substance formed is 

 called peat or muck. This material does not run high in the 

 essential elements; it averages about 0.7 per cent, of nitrogen and 

 about 75 per cent, of water. The phosphoric acid and potash con- 

 tents approximate what is contained in good soil. The value of 

 this substance depends upon its nitrogen content which in turns 

 depends upon the amount of organic matter. The nitrogen is 

 not perhaps as available as that in cultivated soils and unless it 

 is easy to obtain it is doubtful whether it pays to use it.* 



