3^3 
Manuria Treatment for Para Rubber on 
Heavy Clay Soils. 
The following treatment is to be recommended for clay soils?— 
Slaked lime ... Vi to i ton per acre 
Basic Slag (phosphate manure) 350 lbs. „ „ 
Ammonium Sulphate ... 150 „ „ „ 
Potassium Sulphate ... loo „ „ ,, 
The lime and basic slag should be applied about a month or two 
months before the other manures as they decompose Ammonium 
Sulphate. 
The Ammonium Sulphate and Potassium Sulphate should be 
mixed together and then mixed with earth and subsequently spread. 
If concentrated manures are used they frequently injure the 
roots with which they come in contact, and the earth is added as a 
diluent. 
With trees one or two years old it is preferable to dig a shallow 
trench (4 to 6 inches deep) at a radius of 2-3 feet round the tree, 
sprinkle the manure round and subsequently cover with earth again. 
With older trees, where the roots interlace, the manures may be 
broadcast and the whole surface forked over. 
The following can be used in place of Ammonium Sulphate : — 
Castor seed cake, or 
Linseed cake, or 
Cotton seed cake, or 
Para seed cake, or 
Ground-nut cake. 
These should be applied at the rate of about 600 lbs. per acre. 
If it is found that the cost of the quantity recommended is cheaper 
than the Ammonium Sulphate, I would recommend their use. 
Instead of Potassium Sulphate may be employed. 
Kainit (12 per cent Potash) 400 lbs. per acre, or 
Potassium Chloride 100 lbs. per acre. 
The cost of the above quantities should be compared with that 
of 100 lbs. of Potassium Sulphate. 
Instead of Basic Slag, Perlis Guano or other Phosphatic Guano 
may be substituted. 
Perlis Guano (containing 15 per cent. Phosphoric Acid) at the 
rate of 500 lb. per acre, should be very economical, as its price is 
is only $25/- per ton. 
In the first instance as a trial I would suggest the use of the 
most economical fertilizers, until more is known of the different 
