332 THE TROPICAL AGPJCULTURIST. [Nov. 1, 1900. 
« 
To the Editor. 
SCIENTIFIC MANURING AND Tf5A. 
London, Sept. 20. 
Sib, — The importance of the bubject and 
the deep interest that is taken in the ett'ects 
of manure by Ceylon. Tea Growers must be 
my excuse for again addressing you, after a 
delay, owing to my absence from home. 
A point has been made by those who dis- 
agree with me of the fact, that I quoted the 
injurious effect on permanent pastures of the 
continuous application of sulphate of ammonia 
by itself, it being argued that those wlio 
understand the subject would not apply it 
by itself, but only when balanced by a pro- 
per proportion of mineral manure. I des- 
cribed the condition of the plot treated with 
sulphate of ammonia by itself for the same 
reason that I presume it was applied, namely, 
that it is only when one manure is used with- 
out others that its effect can be determined. 
But as regards the effect of sulphate of 
ammonia when balanced by other manures, 
on plot 9 of the Rothamsted experiments, 
sincfi 1879 the following mixture has been 
applied per acre :— 
500 lb. Sulph. of potash 
100 „ Sulph. of soda 
100 ,, Sulph. of magnesia 
3| owt. Superphosphate 
400 lb. Ammonia salts 
which, it will be admitted, is a comi:)]ete or 
" balanced " manure : the average yield has 
been 58 cwts. of hay an acre, against 2i cwts. 
from the unmanm-ed. The grass is however 
rank and of extremely poor quality, almost 
valueless for feeding purposes ; the finer 
grasses here are dying in patches, so much so 
that I feel sure that no one who saw the 
plot as it is now.would care to risk the health 
of any perennial plant by the use of a manure 
so exhausting to the soil. 
I went over the Rothamstead experiments 
with Mr. Joseph Fraser and Mr. Forsyth 
and was glad of the opportunity of discussing 
the matter with two such good cultivators 
of tea and with one who understands 
manuring so thoroughly as Mr. Fraser. 
I pointed out to them what I venture to 
say those who study the reports only and 
do not see the plots, do not find out and 
that is that though the yield of hay is good 
from the plot referred to, small patches are 
failing and that the hay is almost valueless, 
owing to its being so rank. 
We went over, too, the Barley experiments 
which confirm the conclusion conae to at 
Rothamsted against the use of sulphate of 
ammonia ; now barley obviously requires a 
quickly acting manure, for it has to grow and 
mature between May and September and here 
the plot manured with rape cake and 
mineral manure was in better condition and 
shows ahiglier average yield than that treated 
with sulphate of ammonia and inineral 
manure, though the quantity of nitrogen sup- 
plied in l)otl) cases is the same. 
You will have seen that since I last wrote 
t,o you Oil tliiy subject, Sir John Laweshas 
died ; in his death Agriculture has sustained a 
great loss and for myself I feel with deep 
regret that I shall no more be able to con- 
sult one who has always ready to give the 
result of his experience to anyone who 
showed ;in interest in scientific agriculture. — 
Yours truly. G. A. TALBOT. 
ARTIFICIAL MANURING OF TEA. 
REPLY TO MR. TALBOT. 
Lake Bungalow, K;indy, Oct. 9. 
Sir,— It is gratifying to see by Mr. Talbofs 
letter of 20th Septemljer to you that arti- 
ficial manuring of tea has its importance 
admitted, tliough tardily, in a quarter where 
all sucli manuring used to be deprecated. 
As regards the use of sulphate of ammo- 
nia, Mr. Talbot throws no further light on 
the question. DouV)t!ess it was applied alone 
at Rothamsted for the purpose Mr. Talbot 
mentions ; but its tendency to exhaust the 
lime in the soil nmst have been chemically 
kr.own before the practical experiment, to 
which he refers, was made. In .all probability, 
therefore, it was not applied for a series of 
years only to i)ro\ e that tendency, already 
deduced, but tt) Vvatch its general effects on 
permanent pasture. This can hardly be said 
to apply to tea cultivation. 
Nor, 1 think, can any rational conclusion 
be drawn, of any use to the tea j^lanter, 
from the results Mr. Talbot quotes ot the 
application of a mixed manure over a series 
of years to a field of hay. Tlie mixture is 
such as no prudent planter would apply to 
te.a and there is not much similarity be- 
tween a hay crop and a tea field, and a vast 
difference in the climates in which the two 
have to be grown. 
That an immense amount of information 
and interest for the tea planter is attached 
to the Rotha-msted experiments goes without 
saying, but Mr. Talbot has ]iot given us the 
benetit of anything useful yet, though I 
understand he lived in the neighbourhood 
and paid frequent visits. 
I have used sulphate of ammonia for tea 
years, but never, of course, alone, and I use 
it still ; and it is within my knovrledge that 
Mr. Joseph Fraser has done so for a year 
or two longer and still does so. No bad 
results of any kind have yet shown them- 
selves, and that is all any one can say. It 
may, however, interest your re.aders to know 
that Mr. Fraser v/iote me after his visit to 
Rothamsted as follows: — "The visit to 
Rothamsted disclosed no new fact, in regard 
to sulphate of ammonia and its distinct 
tendency to exhaust lime, that I was not 
aware of. As regards the ajipearance of the 
grass plots, it might quite reasonably have 
been expected," &c., &c. I need not take 
up more space by quoting from his letter, 
for doubtless vou will hear from him direct. 
—I am, &c., ' A. MELVILLE WHITE. 
Coffee in Dutch Guiana.— Ouidr to ths very 
low prices obtained for the coffee grown in Dutch 
Guiana, wliioh is almost entirely of the Liberian 
variety, it is on some estates being Hf^^du^^ly 
replaced by cocoa. The crops for 1899 uas 360,481 
kiloii, —Plantinf) Opinion, Sept, 2i). 
