8 BULLETIN 1286, U. S. DEPARTMENT OF AGRICULTURE 
countries than in the Far East. In the Guianas it is said to require 
three to four months' time before all the trees in a planting have 
lost their old leaves and grown new ones. Large variations also 
occur between different branches on the same tree in the time of 
dropping their old leaves. 
As noted on July 24, the foliage of this younger planting was 
everywhere discolored, twisted, or crumpled, and falling off. (PL 
III, fig. 1.) In most cases the leaflets had dropped in advance of the 
long, slender petioles, giving the ends of the branches a peculiar 
bristly appearance. (PL III, fig. 2.) On other trees the naked 
succulent branch tips themselves were discolored, and stem swellings 
farther back indicated still earlier infections. A number of trees 
had died the year before and the amount of die -back, although less 
evident on account of the defoliated condition of the trees, was 
nevertheless outstanding enough to show that the planting had suf- 
fered seriously in the past. A more ruinous condition could scarcely 
be imagined. The disastrous effect on the flow of latex from the 
repeated defoliations in combination with relatively high labor prices 
has naturally made further tapping unprofitable, a situation which 
is said to exist practically throughout the colony. 
DUTCH GUIANA 
The condition of rubber cultivation in Dutch Guiana appears to 
be even more serious than in British Guiana. Bancroft (3) called 
attention to this in 1917. A probable explanation is found in the 
relative positions of the plantings in the two countries with reference 
to the seacoast, those in Dutch Guiana having generally been farther 
inland, away from the protective effect of the coastal winds, than 
those in British Guiana. Also the plantings in Dutch Guiana were 
in closer proximity to the indigenous Heve&guyanensis, which every- 
where in the jungle was naturally infected with leaf disease. 
As in British Guiana, the industry here has been practically aban- 
doned. Two reasons for this are commonly given, the great reduc- 
tion in yield on account of the leaf disease and high labor prices. 
The net result is a production cost which makes competition with 
other countries nearly impossible. About 3,000 acres were originally 
planted with Hevea; but, in contrast with the industry in British 
Guiana, this was mostly in mixed culture interplanted with coffee. 
In recent years most of the trees not killed by the leaf disease on 
several estates have been cut out to improve the condition of the 
coffee or other intercrop. 
In a small planting on the experiment station farm at Para- 
maribo the disease was observed in its typical form, though it 
Avas not at the time in a very active stage. The amount of die- 
back caused by earlier defoliations is indicated in Plate II, Figure 2. 
Here the writer conferred with Dr. Gerold Stahel, director of the 
experiment station, whose valuable researches on the leaf disease 
have already been mentioned. Although, for lack of time, very 
little rubber was personally inspected, the impression gained from 
conferences with various officials and business men indicated little 
hope for the future of rubber cultivation in the colony. 
