FERTILISERS FROM THE OCEAX. 1S5 



From I acre of land Tobacco takes in the seed and straw 2,^ lbs. 



of Phosphoric Oxide. 

 .From I acre of land Lucerne takes in the seed and straw 39. i lbs. 

 of Phosphoric Oxide. 



Potassic Oxide. — Potassic Oxide in the plants takes part in 

 the formation of Starch and Sugar, and it passes with the Car- 

 bohydrates (Starch and Sugar) from cell to cell. It is associated 

 with the Starch and Sugar in the plants in a similar manner as 

 Phosphoric Oxide is associated with the albuminoids. To this is 

 •due in a great measure the success of viticulture in the Western 

 Province, as our soil, being form.ed by the disintegration of granite, 

 "is rich in Potash. 



With reference to Potassic Oxide in the plants the following 

 facts have been ascertained. 



All those parts of plants in which vegetable growth is pro- 

 ceeding are rich in Potassic Oxide. Wherever the formation of a 

 'new cell goes on in the plant — buds, young shoots, young leaves, 

 freshly formed bark, cambium tissue — Potassic Oxide is the pre- 

 ponderant inorganic constituent. Young leaves and parts of plants 

 always contain more Potassic Oxide than old leaves. The Potash 

 'Compounds in plants have a tendency to migrate into those parts 

 where work is to be performed. In the young leaf the ashes con- 

 sist essentially of Potassic Phosphate and Potassic Carbonate, 

 while in the old leaves they consist of Calcic Oxide and Silica. 



The leaves of plants contain more Potassic Oxide than other 

 parts of plants. Hence all plants full of leaves, such as herbs, 

 clover, grass, tobacco, hops, vegetables, cabbage, etc., contain 

 large quantitites of Potassic Oxide. 



All plants and parts of plants in which a considerable amount 

 ■of carbohydrates is stored up also contain a very large amount of 

 Potassic Oxide. As an example of the amount of Potassic Oxide 

 j-equired by various plants we give the following : — 



From I acre Wheat takes 30 lbs. of Potassic Oxide. 



From I acre Tobacco takes 60 lbs. of Potassic Oxide. 



From I acre Lucerne takes 107 lbs. of Potassic Oxide. 



From I acre Potatoes take 108 lbs. of Potassic Oxide. 



Calcic Oxide or Lime. — Lime is absolutely necessary for all 

 -plants in all stages of development. It takes a prominent part in 

 the transformation of sugar and starch into cellulose. It also 

 gives a certain firmness to old leaves. iVIany diseases in crops and 

 plants are solely due to want of Lime. The addition of Lime to a 

 soil accelerates the decomposition of organic matter in the soil 

 and assists in rendering all the constituents of manures and fer- 

 tilisers available to the plant. 



It destroys the acidity of the soil by neutralising the organic 

 acid formed in a sour soil. It decomposes very energetically the 

 unavailable mineral constituents of the soil and changes them to 

 combinations in which they can be absorbed by the plants. 



It acts on the debris of rocks, rendering the Potassic Oxide in 

 such mineral matter more available to the plants, and this would 

 be an excellent manure for a granitic soil. 



