16 
Costs of Tillage and Fertilizers. 
Establishing Cover-crops .- — I will give in some detail the cost of 
establishing Centrosema plnmieri as this is one of the most promising 
cover plants for rubber clearings. The seed is dibbled in at distances 
of three feet apart each way at a cost of $3 per acre, 3 pounds 
of seed being required. The price of seed, at present, is from 
25y to 50 cents per pound, which is somewhat high on account of the 
limited areas planted. The cost of weeding until the plant is well 
established amounts to about $3 per acre and if this sum is charged 
to ordinary estate weeding it will be seen that the total costs amount 
to from $4.25 to $5 per acre. The seed is sometimes broadcast at the 
rate of ten pounds of seed per acre on a well-prepared surface, but 
dibbling is preferable. 
Canamlia ensiformis is best dibbled in three feet apart requiring 
8 pounds of seed per acre or 15 pounds if broadcast. The cost of 
weeding until Canamlia is established is higher than in the ease 
of Centrosema, owing to the habit of the plant. 
It may generally be taken that large seeds such as those 
mentioned above give the best results when dibbled in, while small 
seeds such as horse gram require to he broadcast. When broadcasting 
is the method of sowing, the land is first changkolled or forked to a 
depth of about three inches, sufficient to provide a good seed bed. 
and this will cost from $2 to $3 per acre. 
Horse gram ( Doliehos bifiorns) sown broadcast requires 12 pounds 
of seed per acre, which can be obtained in the local markets at 
six to seven cents per kati. The cost of broadcasting is 25 cents 
per acre. Sarawak bean (Doliches Kosei ) is best established from 
cuttings and this system of planting is slightly higher than dibbling 
on account of additional cost of procuring and planting cuttings. 
Terracing . — A six-foot- terrace made by three feet cutting and 
three feet filling in costs 25 to 30 cents per 50 feet length, which 
amounts to about $10 to $12 per acre allowing on an average 20 feet 
between the terrace®. It might be mentioned that the cost of 
maintaining well-made terraces is small, considerably less than upkeep 
of drains. 
Dynamite . — Sixteen cents per charge, inclusive of labour, is a 
reasonable figure, one charge per tree is generally what is allowed 
but with heavy clays more may be inquired. 
Cultivation . — The following are the actual costs of various 
methods of cultivation, conducted at Castleton Estate on a heavy 
soil. Plot 1, three crops of horse gram were grown within a year, 
at a cost of $17.45 per acre. In Plot 2, surface weeding was 
conducted monthly at a cost of $10.71 per acre per annum. The 
treatment in Plot 3, was monthly weeding and changkolled twice 
per year to a depth of four inches which amounted to $18.27 
per acre per annum. Plot 4 was changkolled once every three 
