iSTovEMBER 2,1891.] THE TROPICAL AGRICULTURIST. 
the costs are nearly equal the planter must first con- 
Bider liis true requiremeuta, and the suitability of the 
mannre to bis working conditions, clinaate, soil, &c. 
If it is necessary to assist the trees over a bad attack 
of leaf disease, which by denudioij them of leaf pre- 
vents the ripening of crop, quiok acting manures are 
essentials ; and though costing more per unit ton are 
the cheapest in the end, as they will ofteu repair the 
damage before it is too late ; they should ba carefully 
backed up so that the first good effects are nob lost. 
Ammonia and lime may be looked upon as stimulants, 
and like spirituous liquids must be used with discre- 
tion, a little whisky or wine often aids digestion but 
it is advisable to have something in the stomach to 
digest, otherwise the results are not satisfactory. So it 
is with plants if you give them stimulants, you must 
give them food to digest: they must have phosphates, 
potash, sulphur, chlorine, iron, &o. &c. As regards 
phosphates we have a wide choice ; there are bones, 
raw of varying grades of fineuees, steamed bones, and 
bone ash, mineral phosphates, precipitated phosphate, 
superphosphate, guanos, and tish. Disregarding the 
native manures we will just consider the phosphates 
pure and simple; they should be in such a physical 
condition that they may bo easily mixed with burnt 
earth &c. Bone ash and mineral phosphates should 
be sufficiently fine to allow of at least; 90 per cent 
passing through a sieve of 80 meshes p3r linear 
inch. The amount of phosphates in bono ash accord- 
ing to MacAdam varies from 62 to over 80 per cent; 
pure or bone ash contains 86'34 per cent and the 
average of six samples analysed gave 73-5 per cent. 
It is usually sold on a basis of 70 per cent. It is 
much more readily takea up by the plants than 
raw bones, and i? an excellent fertilizer where phos- 
phates are required. 
Of mineral phosphates high class Spanish, commonly 
called Estcamadurite, has from 75 per cent to 82 
per cent phosphate-; inferior qualities are often in the 
market with only 50 per cent or so in them. Canadian 
and Norwegian apatites andaruba phosphate are gener- 
ally very rich having sometimes as much as 90 per 
cent tricalcio phosphate. There are a gx-aat number 
of others but ihese are the most suitable, and I 
prefer aruba as it is as soft and easily decomposed 
as bone ash, and is geneially cheaper. 
Prijciptated phosphates are in a muoh more 
beautiful physical condition than it is possible 
to- produce by mechanical means and they are 
almost as valuable as super phosphate the 
average percentage of phospates is about 60 per 
cent. A high class superphosphate with 44 to 45 
per cent soluble is as a rule worth twice as much 
per unit as raw bone flour the physical condition 
ia perfection and the food is at once available for 
the plant. 
Trees bearing a heavy crop suffer from a bad 
attack of leaf-disease, we wish to assist them, and 
determine to apply a complete manure ; cattle manure 
at once suggests itself, the weather is favourable 
and it is applied, the trees slowly feol its effect and 
recover, but there is a good deal of light coffee and 
some of the crop has dropped. AVe try bones, oil- 
cake, and woodaahes ; the results are much worse 
than with the cattle mannre, the mixture is too 
slow in action. 
Next snperpbosphate, ammonia sulphate and kanite 
are tried, the trees feel the effects at once and 
throw out a grand flush of leaf, and the leaves fill 
oat in a wonderful mannre. If we know the com- 
position of the soil we can proportion the manure 
to suit it and the plant's requirements and produce 
the greatest effect at the least cost. 
In tuot the value of a manure to the tree or plant 
depends on the proportion in which the oonstituients 
are in it ; the fertility and suitability of a soil for a 
given crop depends on the relative proportioa that 
the easily assimable elements bear to one another 
and its physical condition ; from this it follows that 
if there is a proportionate deficiency of any eloment 
in the soil that is not supplied by the manure, the 
results will be to say the least disappointing. 
The heaviest loss of value occurs when the manure 
(ipplied hat) (he samo deficiency as th^ SQil. A soil is rich 
in phosphates and nitrogen and we feel surprised that 
bones and oil cake produce no result, commensurate, 
with the expenditure; cattle manure does much better, 
therefore the natural couc'usion is that it is the 
better manure for coffee, probably the addition of a 
little kanite would improve the bone and cake 
mixture, but it is by no means improbable that if it 
did so, it would also improve the cattle manure, and 
an analysis of the soil would reveal the fact that 
the soil was short of magnesia, chlorine, sodium, potash 
or possibly sulphuric acid, and it is quite possible that 
the kainite alone would have givan as good results. 
It to the cattle manure we add what the soil de- 
mands to supply its defects we can manure with the 
cei tainty, provided the season is favorable of obtaining 
good crops, and io bad seasons fair ones and a full 
return for the money spent on manures, soil analyses 
such as those given by John Hughes and myaelf 
which sho'v the relative proportion of the elements 
available for plant food to enable the planter to econo- 
mise in his rainuring by applying the necessary 
manure, avoiding the application of what ia unneces- 
sary.^^nd the disappointment and waste of money 
attendant thoreou. 
To make manuring a success and to ascertain the 
value of a manure to him on his estate a planter 
must consider the following points ; — 
1. His soil. 
2. His produce. 
3. Carriage. 
4. Capital. 
5. Labour. 
Without the last two manuring and manarea are 
impossibilities, and if the supply of these two 
necessaries is limited, the planter must out his coat 
according to his cloth ; if the supply is insufficient a 
planter's best efforts are often crampad, and he has 
to work when he can, not just when he wishes to, 
and knows he will get the best result. 
Work well done at the right season ia the cheapest in 
the end, and the manure best adapted to his soil and 
produce is the most economical to use. 
WILLIAM PBINGLE. 
Bangalore, Sept 20th, 1891. 
4 
COCONUT AND PALMIEA PALM CUL- 
TURE IN THE NORTH OF THE ISLAND. 
If it were not that palmiras are so slow of 
growth, wa should feel strongly inclined to advisa 
our oorresporideat, the Pallai planter (see his letter), 
to leave the plants to grow amongst the coconuts. 
There would then ba a valuable sugar, fibre, and 
timber yielding property to fall back upon, when the 
coconut palms had passed from maturity to decay, 
which W6 suppose they'are likely to do at an earlier 
stage of existenos in the Northern portions of the 
island than in the Western and Southern ? Thia is 
just one of those oases where the practical experience 
of a man like Mr. Jardine would entitle him to 
ba heard with regpect, — at home as he is in 
coconut, oaoao, cinnamon, coffee and tea culture. 
We fancy he would say, " I£ the palmira plants 
must be sacrificed, ao as to give the coconut palms 
full room and nutriment, and if there ia danger 
of grubs, burn all save the leaves, and bury leaves 
and ashes round the roots of the coconut palms." 
This ia our advice, if there ia no doubt of the 
superior value of a coconut grove of 70 trees to 
the acre, to a dense forest of palmiras at the 
rate of several hundreds to the acre. 
But tha letter of our correspondent gives ua a 
new idea of the ease with which the Forest Depart- 
ment could grow palmiras over a large portion 
of the northern districts of the colony. We suppose 
the jungle from which our correspondent's estate 
was formed ia a fair specimen of the forest gene- 
rally. I£ so, vast tracts of jungle are filled with 
