THE TROPICAL AGRICULTURIST. 
707 
Trees. — Notes on a few on trial at Hakgala will be found in the report of the Superintendent. 
A detailed study of the Ceylon species of Diospyros and their timbers (ebony, calamander, &c.) has 
been undertaken by Mr. Wright, whose report is given below. 
Ornamental PZawfo.— Cannashave continued in great request, and are nowa conspicuous feature 
in most Ceylon gardens. Other ornamental plants are also in demand, and the interest in horticulture 
in the Island seems increasing. 
JOHN C. WILLIS, 
Peradeniya, January 25, 1901. Director. 
SUPPLEMENTS. 
1.— REPORT OF GOVERNMENT MYCOLOGIST AND ASSISTANT DIRECTOR. 
During the six or seven months that I have been engaged with the work of my appointment 
nearly 200 inquiries have been dealt with, chiefly dealing with diseases of economic plants. The 
unusual number of dull days with a humid atmosphere has been most favourable to the growth 
and spread of parasitic fungi during last year. 
Both in the field and laboratory the fungus causing grey blight, Pestalozzia Guepini, Desm., 
has received a great deal of my attention. In order that the life-history of a fungus may be known 
it is necessary to make cultivations from the spores and continuously watch the growth of the 
organism with the microscope. These cultures are, as a rule, grown on a gelatinous medium, or some 
substance favourable to rapid growth ; unfortunately the behaviour of the fungus in this artificial 
cultivation is often quite different from when it is grown in nature in living tissue. 
The spores and living mycelium of Pestalozzia and several other parasitic fungi have been 
cultivated and examined in this manner in the laboratory, and, with the object of making observations 
and experiments on the fungus as it grows on the tea leaf, ten healthy bushes from two to five years 
old were transplanted to an experimental bed outside the laboratory. These were carefully removed 
without much injury to their root system, and have all continued to grow vigorously. With the help 
of these experimental bushes and material in the laboratory, it is hoped to work out the complete 
life-history of Pestalozzia and other parasitic fungi on tea. 
A series of experiments has been planned and will shortly be established with a view to 
obtaining a more exact knowledge of the distribution of spores of grey blight and other leaf disease fungi. 
Six stations have been selected at elevations of 50, 1,600, 2,500, 3,000, 4,000, and. 5,000 feet 
respectively. At these places a jute hessian screen or tabernacle open at the top, 9 feet high, 45 feet 
long, and 8 feet wide, enclosing two rows of 15 tea bushes — i.e., 100th part of an acre — and placed at 
right angles to the prevalent winds, will be erected. 
The bushes inside this enclosure will be pruned (at the same time as the rest of the field) and 
all leaves taken off the bushes and swept out of the enclosure. Much interesting information should 
be gained by observation of the conditions as regards " grey blight " and other parasitic fungi of the 
enclosed bushes and those outside on either side of the tabernacle. 
In order to test the practicability of taking off all diseased leaves from tea bushes an experi- 
ment was carried out at an estate of 4,000 feet elevation. The bushes first selected had gone 12 months 
from pruning ; they were big healthy bushes with little, if any, disease apparent. All leaves with 
any spot due to fungus or insect were taken off, as it is impossible to instruct coolies as to any special 
blight. A quick " podian " plucked the leaves, and was closely watched to see that no leaves with any 
spot were left. The time taken was nearly 6 minutes per bush, or 10 bushes per hour, and about 
60 leaves were taken from each bush. Ten weeks later these bushes were examined and only three 
leaves were found on 15 bushes with "grey blight," and a few with insect injuries. The surround- 
ing tea was, however, not attacked to any extent. A second series of bushes in a field which had gone 
22 months from pruning were treated in the same way ; the bushes were healthy, but the leaves were 
spotted, and a large quantity of dead leaves were on the ground. In thi3 case the time taken was 
41 minutes to a bush, and nearly 3,000 leaves were plucked from each bush ; in some cases 90 per 
cent, of the leaves were taken off. 
It appears from this trial that such measures to prevent the spread of leaf blights when 
adopted should be taken as soon as possible after pruning, when the number of spotted leaves is few ; 
and no doubt the most economic and most effectual method will be found to carry out this treatment 
periodically with the plucking by making the pluckers take off all diseased leaves. 
