May 1, 1899.1 THE TROPICAL 
AGEICULTURIST. 
749 
revealed by asrioultural research in recent years are 
not only very encouraging but of the highest impor- 
tmce to the cultivator. He now underst-iu is how 
the defeots in a soil can be remedied at the least cost. 
Indeed a bad soil can soon be converted inioagood one. 
It has already been stated that the Ooor^^ soils are 
naturally good, therefore the planting industry was 
commenced on favourable terms ; and bumper crops, 
obtained without mucli cultivation, were the order 
of the d*y for many years. But as time went on the 
shrub became less productive, and coffee pests of 
Borts commenced to attack the cultivation. It was 
then realized that the natural soil was becoming 
deficient in something which only heavy manuring 
could restore, and henceforward, manuring estates 
became a necessity. What the planter is chiefly 
interested in at the present day is how to restore to 
the land, in the cheapest and most efficient form, what 
his crops remove from it. 
Agricultural chemists tell us that only three prin- 
cipal substances need be applied in the form of 
artificial manures. These are nitro[/en, phosphoric 
acid and potash. 
WEEDING. 
The incursion of weeds on cultivated land has 
always been looked upon as thriftless husbandry, and 
generally speaking, we should take that view of it in 
coffee cultivation also, as the demand made up^n the 
land by tree and coffee roots is already more ih m it 
can bear. But the primness of a flower-garden is 
not required on the estate, and in some exposed soils 
of a stony nature I instinctively felt that a light 
covering of weeds would have done good by cooling 
the over-heated surface. The prevailing weed in the 
plantations is ^Zitinea Wiiihtiana, DC (Kan " Gabbn 
Soppn"). It is an annual herb of rapid growth, and 
abounds everywhere in two varieties, determined by 
■white and purple flowers respectively. Considerable 
expense is incurred annually in the destruction of 
weeds, bnt the outlay is compensated to some extent 
by the gr ;en manure which is thus secured to the soil. 
If weeds of annual duration, such as Blumea, have 
their tops cut off before flowering, they will do no 
harm to the coffee and comparatively little to the sail. 
I was favourably impressed by the clean cultivation 
which mostly prevails all over Coorg. 
MANURES. 
Valuation of JLzmires. 
The manurial subitances at the planter's disposal 
are of several kinds and may be ruughly classed as 
follows : — 
(a) Jifanures having both a direct and indirect 
action on the soil:— 
Cattle manure of all sorts. 
Green manu; e of all sorts. 
Sewage. 
Composts. 
Humus top-dressing. 
Bones, when largely applied. 
Guano do. 
(h) Such as act indirectly: — 
Lime. 
Marl. 
Chalk. 
Gvpsum. 
Salt. 
Lime is of the highest importance to coffee land, 
ai in addition ti acting beneficially on humus, it 
\ i the siilifiable base for the piocess of nitrification, 
(c) INlanures having a direct and comparatively 
quick action: — Bone-meals, dissolved, and in 
sulphniic acid; Guano, including fish guano, 
and fl^sh guano such as Mr. Petiie Hay 
prepares at Hunfur. 
Oilcake— Poonac, caste, honge, etc. 
Nltrao of So'ln. 
Suporpho^-phates. 
Sulphate of Ammonia. 
Sulphate of Potash. 
Muriate of Potash. 
Mineral Phosphates. 
Kainit, 
A most valuable fertiliser of this class, recently 
discovered in the dehris of steel factories in Europe, 
is hasic slay. 
Of the abovenamed manures I shall now attempt 
briefly, to show which are most valuable in provid- 
ing iiilroijcH, phos/ijioric acid anl potash, leaving 
the cultivator to use his own discretion in a final 
selection. But manure in name and the substance 
in reality are often quite different things, and in 
the case of portable manures at least, I would 
strongly advise careful analysis. 
Nitrogenous Manures. 
Nitrogen in its different firms may be said ti he 
present in everything. But for purposes of cultiva- 
tion we mostly require it in the (orms ol jt if ric acid 
and ammonia, of which there is often a deficiency 
in impoverished or over cultivated soils. It is, 
therefore, in the application of substances rich 
in nitrates and nitrites that we are likely to main- 
tain this indispensable constituent in a form suitable 
to the growth of plants. The fixation of free 
nitrogen from the air through the combined action 
of leguminous plants and bacteria is a recent 
discovery of great value to the agriculturist. Nitrogen 
abounds in humus, anl is found in varying quantity 
in all decaving organic substances. 
The artificial manures which contain it in the 
largest proportion are nitrate of soda, sulphate of 
ammonia, Peruvian guano, bones, fish and flesh 
guanos and oilcakes. 
All these are now used on coffee estates. 
Phosphate Manures. 
Next in importance to nitrogen, as a soil consti- 
tuent, comes phosphoric aci *. But as the latter 
enters largely into the composition of the coffee 
bean it is really of almost first importance to the 
planter. It is fortunate, therefoi e, that the crumbling 
rocks of Coorg are well charged with this useful acid, 
apatite, carbonate of lime, and the decaving felspars 
being the usual basis for it. Bare, arid tracts with 
occasional stunted vegetation indicate its scarcity, 
as plants are unable to grow without it. Coprolitea 
abound in it- In nature. Phosphoric acid is mostly 
insoluble, occurring as phosphates of lime, alumina, and 
iron, etc. For convenient restoration to the land 
we have numerous artificial manures, such as 
guano, bones, basic flag and all the mineral 
phosphates. But for quick effect on growth the 
soluble superphosphates are the best, especially the 
double superphosphates manufactured at Wetzlar 
jn Germany. 
Potash JTanures, 
Although not so important to growth and repro- 
duction as the preceding constituents, still, potash ia 
an indispensable factor in the raising of crons. It is 
naturally abundant in old rocks — especially felspar — in 
decaying vegetable matter and in the salt-water of the 
ocean. It is the princip il ingredient of the ash when 
a plant; is burnt. Mr. Sprott, of Hollery, burns the 
no.'cious Lanfiiiia C'amara, to utilize its potash on the 
estate. In a country situated as Coorg is, one would 
think that Potash would never be wanting : dense ve- 
geta'ion, sea influence, and crumbling felspar rocks 
being natural conditions. Still, the application of this 
mineral by artificial means has proved highly 
beneficial, aird it can only be surmised that the 
nat'ural product ia in some way irlow or defective 
in action. Sulphate and muriate (chloride) of potash 
are the two artificial forms in which this mineral is 
quickly restored to the soil. Diied blood is also good 
for the same purpose. 
Application of Manures. 
Having now classified the important manures under 
their respective headings, it is necessa' V to s ly n few 
words regarding their applic.ition to d CFerent kinds of 
land. S )ils poor in orginic m Uter are usually the 
most benefited by the application of nitrogenous 
manures. J5ut some of the latter, such ns nitrates, 
ammonia salts, and a few organic forms of nitrogen 
act so quickly on the soil that thoy should only bo 
applied as top-dressings at the time tlio crop most 
