Nov. 1, 1899.] THE TROPICAL AGRICULTURIST. 
805 
THE CULTIVATION OF TEA: 
MEASURES TO PREVENT DISEASE. 
COMMON SENSE TREATMENTS, CALCULATED TO 
HOLD GREY AND OTHER BLIGHTS IN CHECK, 
COMBINED WITH PROFITS TO THE ESTATE. 
I doubt not that such direct treatment as 
the picking off of diseased leaves will (as cal- 
culated to defoliate bushes) soon be held as of 
minor importance, in the treatment of Plant 
Diseases, and it might, therefore, be as well 
to review some methods, which, though in- 
direct, might be looked upon as far more 
effective, and the least that can be expected 
if such methods are carried out carefully, is 
that the increased returns from the tea treat- 
ment will cover the cost of such. 
Burying Prunings.— As being the most 
important of such, let us first take the Bury- 
ing of Prunings. Dr. Watt's remarks on 
this subject, are worth reading. He seems to 
have concluded from the result of his flying 
visit to Assam, etc., tha.t prunings should 
not be buried for the reason that they would 
be likely to foster parasitic growth— (though 
in stating this I might add that he mainly refers 
to Thread Blight, a pest peculiar i7i that it 
spreads by long fibrous mycelium, has the 
power of living on the dead buried matter, 
and of afterwards resuming its parasitic life 
on adjacent plants) -and I do not think his 
remarks apply so much to grey and kindred 
blights. However, both he and Mr. Massee, los- 
ing sight, I am afraid, of the object for which 
we grow tea, recommend the burning of pri^n- 
ings, condemning burying. Neither mentions 
the use of disinfectants in connection with 
such operations, and yet at the same time 
they have a lot to say about the great value 
of time, etc., as fungicides. So perhaps, we 
who are the most interested, might be per- 
mitted to view the matter in a more practical 
light and look upon burying as our cheapest 
and most feasible means of treatment— with 
two great advantages over burning: (1) a saving 
of almost all organic matter in the prunings, 
and (2)pi'unings -would not have to be carried 
some distance— as in burning, in most cases — 
to suitable open spaces. It follows that doing 
so wo\ikl give the wind every chance to 
scatter spores to great distances, whereas in 
Inirying a yard wotild represent the greatest 
distance to a place of burial. Prunings can 
be well buried— including careful sweeping 
of the ground, and the cutting of deeper holes 
than usual— with a dose of about 500 lb. of 
lime i)er acre, at a cost of about 1120 ; the 
lime added quickly decompose.? the mass 
buried, as well as acting as an indirect manure 
by fi'eeing potash, nitrogen, etc., which may 
be locked up in the soil, in an insoluble form. 
As lime could hardly be used every time a 
field was pruned, some substitute might be 
foi'med, in solutionslike the Bordeaux Mixture: 
such could easily be sprayed on the collected 
mass by the aid of an ordinary watering 
can oi' something of that kind, the only 
drawV^ack at present being the pi'ohiliitive 
cost of sulphate of copper, as probably about 
50 lb. would be used per acre. However, 
where this chemical is used in large quanti- 
ties, it is extremely cheap ; and, no doubt, 
when a demand was felt here, we should be 
able to purchase at a figure warranting our 
using such past experience on estates where 
prunings were buried solely iu the way of 
f9 
manuring, thus proving how valuable such 
operations are. Personally I have done such 
woi-k on a small scale for some years with most 
gratifying results, and a well-known property 
on which this system has been carried out 
for some six years, stands probably today 
as the freest from pests and the healthiest 
estate in the island. Mr. Bamber, I know, is 
strong on primings being buried, provided, 
of covu'se, such work is done in a thorough 
manner, and I am sure that we shall find 
he Avill have a good deal to say on this 
subject in the Report he will shortly put 
before us. 
Burning.— Now for Bvu'ning, it is unfortu- 
nate that on almost every estate there are 
places too steep for bui^ying or cultivation 
of this nature, and I believe there is also 
one district where the presence of something 
in the nature of thread blight, prohibits the 
burying of prunings ; on such places burning 
must be resorted to as about the only method 
of treatment available. In this operation the 
value of the manure created plays but an 
vinimportant part, the ash collected from 
the burning of prunings from an acre 
of healthy tea, would give .about 20 lb. 
of potash, 6 lb. of phosphoric acid, and 
about li lb. of lime, losing about 40 lb. 
of nitrogen. This would be utilized were 
the prunings buried and, if these pruningg 
were left undisturbed, most of the Potash, etc. 
in the ash would be available for the plants' 
use. And looking to the difficulty of properly 
re distributing the ashes, it would be ne- 
cessary, when applying artificially, to almost 
double the usual dose, where the ash has not 
being returned— in order to make up for the 
loss of same. 
Destruction of Cheddie.— Mr. Massee 
says, remembering the very different kinds 
of plants on which this fungus is known to 
be parasitic (speaking of Grey Blight) it is 
probable that it also occurs on wild plants 
in the vicinity of tea. If such is the case,— and 
there is no doubt about it — all such should be 
removed if possible, as the Conidia is carried 
great distances by wind and other agencies, 
and no amount of attention to the tea would 
avail if the supply of Conidia necessary for 
inoculation, were grown in the neighbour- 
hood. Now, there are two things which might 
be done with cheddie, etc., with a view to using 
such as mamu'e. It might be buried in 
large pits (accompanied with a little Basic 
slag or Lime to assist rapid decomposition) 
to be afterwards applied as a bulk manure ; 
or cheddie grass, etc., collected, might be 
burnt and the ashes collected under shelter 
till required. This would be of value, on 
account of the Potash and Lime contained; 
the amount of these would vary very much 
according to the class of vegetation, but we 
might take an average of 10 per cent as repre- 
senting the quantity of Potash in the ash. 
Another class of vegetation which would 
come under this head are the dense masses of 
belts and road trees we have in our fields, 
with the idea of either checking wind or acting 
as a fuel reserve. Such trees, it seems to me, 
do a great deal more harm than good, and 
excepting in districts like Udapussellawa 
are quite unnecessary. We will take gums ; 
if we look at bushes adjacent to trees of thia 
description, we find them in a most misei'able 
condition. This is more due to the drip from 
