156 
THE TROPICAL AGRICULTURIST. 
[Sept, i, 1897. 
and when a pest appears amongst our plants it is 
difficult to know what to do. 
The subject of diseases of plants is a wide one, 
too large to be successfull 3 ’ grasped, even after long 
experience, while in many points there is too much 
obscurity as to the cause of disease to allow of 
successful treatment of cure. From the multitude 
of diseases liable to appear amongst plants, two 
classes stand prominently forward : (1) those due to 
the action of parasitic plants particularly Fungi ; 
(2) those due to iujurioirs animals, particularly Insects. 
The remaining diseases have their cause in adverse 
soil conditions, in mistakes of cultivation, in defects 
in the plants themselves, or in other carrses at present 
difficult or impossible to make out. In the present 
series of papers it is proposed to deal with the first 
class of diseases only — with those caused by the action 
of injurious plant-organisms on such plants as are 
useful to the out-door or in-door gardener. Diseases 
of this class are sufficently common and disastrous 
enough in their results to be only too familiar, and 
their importance needs no further emphasising than 
to recall the ravages of Potato Disease, Vine Mildew, 
Damping-off Fungus, and the Hollyhock Rust of 
former days, not to mention the thousand-and-one 
mildews, rusts, and blights of less consequence. The 
subject of fungi is, to the ordinary gardener or culti- 
vator of plants, one fraught with many difficulties 
arising from the minute structure and complex life- 
history of these tiny organisms, and any text-books 
available tend to bring these very difficulties into 
prominence. This is no doubt necessary and valuable 
in its way, yet we believe that, as in a “ first aid” 
ambulance training, it is possible by a few exact 
observations to know enough about a funguspest to 
understand how to proceed against it. We do not 
then propose to deal with the fungi themselves any 
more than is necessary to understand them, but refer 
the seeker after detail in this direction to the books, 
some of these are — Diseases of Field and Garden 
Crops, (1884) Worthington G. Smith; Diseases of 
Plants, Professor Marshall Ward ; Diseases of Trees, 
Translated from the German by Professor W, 
Somerville (Macmillan, 1895) ; Diseases of Plants due 
to Cri/ptogamie Parasites, Translated from the German 
by William G. Smith (Longmans, 1897). 
For all kinds of plant-diseases the ‘treatment is 
one of two kinds; (1) preventive, aimed at keeping 
the disease away altogether ; (2) remedial, which aims 
at destroying the offence. To prevent disease is more 
truly the work of a gardener than to cure it, for, 
after all, his efforts towards remedy cannot go much 
beyond the stage of “ first aid ; ” if more be needed, 
the specialist should be applied to. To keep one's 
plants free from disease requires more skill, foresight, 
and experience than to try remedies; it also demands 
great patience, for, as it were, the results are negative, 
no disease appears; but, on the other hand, the 
value of the crop repays all the extra care in raising. 
William G. Smith, Edinburgh. — Gardener’s Chronicle, 
— -♦ 
LIBERIAN COFFEE. 
The extension of Liberian coffee cultivation in S. 
India, in many cases in an experimental stage, in others 
on a more extensive scale, is ample excuse for my call- 
ing attention to the results actually obtained in Ceylon, 
and a district where there is very so far old Liberian 
coffee not a thousand miles from Cape Comorin. 
LIBEKIAN IN CEYLON. 
In Ceylon in the latter seventies there was a 
considerable amount of land planted with what was 
fondly hoped was going to replace the Arabian 
variety. The original plants were planted at too high 
an elevation, and not making any satisfactory growth 
were removed to a lower elevation, where they throve 
admirably, and I believe brought in the fortunate 
proprietors as much as 4 a». a cherry. What has 
become of all the Liberian planted in Ceylon at th at 
time is not hard to say, as it has practically dis- 
appeared, and to such an extent that not long ago 
I saw Liberian coffee cultivation alluded to as a new 
product in a Ceylon paper. The causes of its dis- 
appearance were various, in many places the soil was 
unsuitable and probably the treatment, and the coffee 
more or less came to an untimely end by starvation, 
death being in many cases accelerated by a mamoty. 
The low price of the coffee was another great cause ; 
I think about 1884 it was only worth some R5 a 
bushel of rice coffee. This cause led to the cutting 
out of some decent coffee, some that I saw being 
so well grown that hitching an elephant on to the 
trees was considered a cheaper and more efficacious 
system of removal than by coolies. There was yet 
another cause, a cause that I hope Indian planters 
may be spared, and that was bug. Bug obtained 
such a bold on the coffee, and throve so well, that 
the only way of getting rid of the bug was cutting 
out the coffee. At the present day I see the Delgolle 
Company refer to Liberian coffee, of which they 
have a considerable acreage of young coffee, in a 
most discouraging way, both as regards present crop 
and future prospects. As the result of all the Ceylon 
experience, it may safely be inferred that Liberian 
coffee wants good soil. Crossing the water there is 
some Old Liberian to be found which bore well and 
steadily for years, but is now unfortunately in a very 
unhealthy state. 
LIBERIAN IN INDIA. 
One dealing along a stream being, I believe, 
affected by the extensive felling of the forest on 
both sides which must have had a great effect on 
the moisture during the dry seasons, and another 
clearing, which was under heavy forest shade, has 
been terribly damaged by thinning the shade so much 
so that it is being densely planted up with artificial 
shade in the hope it may save it. There would be 
nothing very serious in this as it would only point 
to shade being a desideratum for Liberian, but the 
most serious thing is the failure of young coffee 
planted three to four years ago, even when planted 
with shade. This would, I think, point to deterioration 
of the seed, and I am confirmed in this by the 
opinion of the planter who originally planted the 
old coffee, who holds that Liherian does not grow as 
it used to. There is no doubt that looking at any 
lately planted coffee and comparing it with the old 
original trees, that it seems an impossibility for the 
stems to attain the same size within any reasonable 
time. There is another item of interest in regard to 
Liberi.an, and that is that the crop has been a complete 
failure last year and the year before through drought, 
the blossom failing to set. That long droughts aie 
not good for it I think may be taken as proved 
by the success of this species in the Straits, where 
I believe they seldom have a month of the year 
without rain. 
DIFFERENT JATS OP COFFEE. 
There is a very important thing to be borne in 
mind in planting Liberian, and that is that there 
are distinct varieties of the coffee, one bearing much 
heavier than the other. So that in starting a Liberian 
as in a tea clearing, the importance of jat is of 
vital importance. From all I have seen of Liberian 
in Ceylon and on the continent, the successful growth 
of the tree seems to require — 
I. Good soil. 
II. Plenty of moisture. 
III. Shade where at all liable to drought. 
IV. Selection of the right jat. 
In reference to the deterioration of the trees, it 
is harder to know how to meet that. Importation 
of fresh seed from Liberia would undoubtedly be the 
best way, provided any guarantee could be had that 
it was the right variety and carefully selected, but 
it is questionable I think whether it would not be 
better to rely on the survival of the fittest ; careful 
selection and cultivation of the parent seed trees 
would I believe be as good a way as any to ensure 
success of future clearings and avoid repeating past 
mistakes. I may be w-roug, but I am strongly of 
opininon that sufficient care has not in many oases 
been paid to the selection of the seed. Taking a 
bushel of parchment out the store for seed is hardly 
the way to command success. I hope some of your 
readers will let us know how far their experience of 
Liberian coffee agrees or differs from the somewhat 
unsatisfactory experiences I have related.— B. Nelson. — 
Planting Opinion. 
