294 
profits are excellent. The growth of the trees at the experiment 
station is most encouraging and compares very favourably with 
the same age trees in Ceylon even at higher elevations, which are 
supposed to be more suitable t for camphor cultivation, some 300 
trees at the Experiment Plantations, Batu Tiga, growing only a 
few 7 feet above sea-level, have attained in two years a height of 12 
to 14 feet. 
Eradication of Lalang. 
The experiments with spraying to the eradicate lalang weie 
continued during the year. /The use of arsenitc of soda was 
found to be effective if properly applied. 
The want of efficient spraying machines at present prevents 
the general trial of this cheap method of killing out lalang and 
other persistent weeds. In addition the prohibitive local cost, 
500-800 per cent, more than retail prices in Europe of the arsenic 
and the soda, make the cost per acre too high to pay. Arrange- 
ments have now been made to get supplies at reasonable rates from 
Calcutta. With the cost of the materials not much more than 
the retail price in England, and an efficient machine which 
gives a fine spray, the total' cost. per spray should be under $1.50 
per acre ; three or four sprays is enough to entire!) 7 kill the 
lalang. No damage is done to the roots of plants growing in the 
same ground, the spray being only a leaf poison. 
Some young rubber plants in pots in which the earth was 
regularly watered with the solution in twice as large a proportion 
as is used in spraying lalang were in no way affected by the 
application. 
An experiment .over spine acres is in course of progress, and 
wh/m finished the reteult with cost of materials, labour, etc., will 
be published. 
Rubber Cultivation at Various Elevations. 
The rubber trees at the Experiment Station, Gunong Ansi, 
are growing vigorously. Mr. \v! F< Rowland, whose estate is at 
the base of the hill, kindly acted as Hon. Superintendent during 
the year, and takes great interest in the progress of the plots, 
which ate situated at regular distances from sea-level to 2,400 ft. 
Measurements of height and girth of all trees are being carefullv 
kept, and these will be published later. 
Scientific and other Visitors. 
Several scientific and agricultural experts visited the States 
durmg 1906 and availed themselves of the information 
at the disposal of the department. Professor Engler, Director of 
the Botanical Gardens, Berlin, and of world-wide reputation as a 
systematic botanist, made a short tour through the States collec- 
ting Aroidae. 
