Si6 
THE TROPICAL AGRICULTURIST. [December i, 1881. 
of the most important steps in combatting the inroads 
of Bemileia is the destruction of fallen diseased leaves 
as speedily as possible. 
1. A mature spore is capable of germination within 
24 hoiu-s of its removal from the parent mycelium. 
2. A leaf which falls while still green in parts may 
continue to shed spores for some hours after reaching 
the ground. 
3. Ripe, dry spores retain their vitality for several 
weeks or even months. 
4. Any of these spores blown from the ground on 
to the new flushes of leaves which become formed after 
the " general attack," &c, may become a new centre 
of disease in two or three weeks after germination. 
I now pass on to the subject of the amount and 
kind of damage done by leaf disease to coftee — a sub- 
ject already treated of at some length in former com- 
munications. 
The Fall of Leaves, Flowers, and Crop. 
§ 13. As I have already shown in a preceding report, 
and as is generally held proved, the most obvious 
damage done to coffee by Hemileia vastatrix is the 
periodical destruction and premature fall of leaves which 
it causes ; if the leaves can only be kept on the trees 
for longer periods, the chief problem is solved. 
Without insisting more in detail here upon the facts 
before published and the additional proofs of the damage 
done now laid before you, I propose to examine a series 
of phenomena which at first appear extraordinary, but 
which a little reflection shows to be naturally consequent 
for the most part on the foregoing. The blossom of 
the coffee tree appears chiefly during the early months 
of the year in the districts south-west of Nuwara Eliya,* 
and this year an exceedingly promising series of blos- 
soms was produced on most of the estates. Part of this 
blossom never came to anything beyond the stage of 
buds ; another portion produced young fruit, but soon 
dropped off; while a small fraction furnished the crop 
now ripening up to a greater or less extent. 
The following remarks apply more particularly to the 
districts above indicated ; but the facts apply eciually to 
other parts of the country as well, making proper allow- 
ances for differences in climate, seasons, &c. 
The trees, which were recovering from the late 
"attacks of leaf-disease" in December and January, 
had commenced to clothe themselues with foliage in 
February and March, but were not generally -luxuriant 
before April ; by force of habit, so to speak, the flower 
buds became formed in the hot weather, and expanded 
as more or less luxuriant blossoms on shoots which 
were still struggling to produce leaves to replace those 
which had been lately lost.t That many of these early 
flowers buds and flowers were poorly nourished on the 
still incompletely clothed shoots, is not surprising, and, 
in contrast with this, it appears that the March blos- 
soms (which were generally better also), coming out on 
shoots already fairly well supplied with leaves, and 
rapidly foiining new ones, were usually the successful 
ones. That this should be the case follows naturally 
from the fact that the latter blossoms and resulting 
young fruit had more material to draw nourishment 
* In some parts of Uva and a few other places, the 
coffee blossoms nearly all the year round, a fact of 
great importance in several respects ; the picking is 
more expensive, but the trees are less exhausted by the 
distribution in time of their arduous task. One Uva 
planter tells me he has had 13 blossoms within 12 
months. 
t A correspondent to a daily paper wrote in June 
from Kotmale to the effect that splendid blossoms were 
general, but a large quantity of the February blossoms 
were destroyed, and similarly in March. Then two small 
blOBBOma in January and one in April should have given 
crop. W is experiweeis also to the effect that manured 
coffee did best. 
from, more leaves being present at the time, and more 
time having been given for the storage of those food- 
materials which the young berries required. 
I found also that the later blossom consisted mainly 
of finer flowers, better nourished and more vigorously 
developed as a rule. Not only so, but on a given estate 
there was more crop " set " on recently manured fields 
than on the fields wliich had received less liberal treat- 
ment ; while comparisons; over large areas convinced me 
that the same held true for trees on good deep soil, as 
opposed (other things being equal) to trees giown under 
poorer conditions. 
But the statement that without leaves the tree can- 
not produce blossom and crop admits of more direct 
proof. In December, 18S0, I stripped all the leaves from 
a tree on an estate in Hantane, and left it to recover 
as it could ; the trees around proceeded to bear blossoms 
as usual in January, February, and March, but this 
particular tree was unable to produce a flower, all its 
energies apparantly having been required to replace the 
leaves.* Here we see that the loss of leaves by the 
ordinary trees (caused by the November attack of leaf 
disease) being made up in time to enable the trees to 
produce blossom, only reacted to the extent described 
above; but the second loss, following on the first, in 
the example given, not only prevented the setting of 
crop, but even prevented the tree from blossoming at 
all. And so with other examples. 
It thus becomes clear that, in the cases referred to, 
the blossoms produced at a time when the number 
and conditions of the leaves did not afford adequate 
nutrition, only partially succeeded in producing the 
required fruit ; while those blossoms which appeared 
later, and were better nourished, yielded more pro- 
mising results in proportion as they were better sup- 
plied with food, &c. 
I have devoted much time to the examination of 
the extraordinary phenomena termed by the planters 
" failure of blossom," and the following summarises the 
results arrived at. A certain proportion of incipient 
flower-buds did not come to anything at all, but 
formed at most yellow, sickly-looking protuberances 
which snapped off at a touch; in other cases the 
young buds opened slightly, and then "rotted off," 
passing through shades of yellow and brown to black. 
These buds and young flowers were peculiarly brittle, 
and their cells were full of brilliant, waxy -looking, dense- 
protoplasm ; the consequence was they would break or 
snap at a touch, and were in no way limp or shrivel- ' 
led. In some cases the flower was more or less 
deformed, the style protruded, and the corolla imper- 
fect, and such flowers often rot away at the centre. 
A large proportion of the flowers, however appar- 
ently in all respects normal, became fertilized, lost 
the useless appendages, and in the ovary remained to 
produce fruit ; nevertheless the fructified ovaiy did not 
swell beyond an initial stage, but turned yellow and 
dropped off while little bigger than a pin's head; or„ 
in other examples, it remained stationary for three or : 
four weeks, and then either dropped or proceeded to 
swell up. 
Another series of events may follow the normal; 
fertilization and swelling of the ovaries of successful 
flowers, and render it by no means certain that the 
fruit will be matured. Many young berries turn yellow 
and sickly when little larger than a pea, and are 
detached with a mere touch ; others acquire the normal 
size, and begin to turn orange and then shrivel up to 
a rotten or "light" brown mass. It thus appears that 
any estimates of the crops, founded on the amount of 
blossom, &c, were this year likely to prove fallacious; 
and that such has been the cause i s well known. 
* Similarly with 20 trees stripped in December, 1880, 
and 40 stripped early sn January, 1881 : on flowers were 
borne by any of them though magnificent blossoms formed 
on all surrounding trees. 
