September i, 1890.! THF. TROPICAL AGRICULTURIST. 
205 
The first series comprise a mechanical admixtAire of 
humus, clay, and sand ; it has a black hue, some‘imeB 
a depth of eight feet, and, when heated, it becnmea 
red from the presence of oxide of iron, and gives off 
an ammoniacal odour. There are several varieties, 
due to the varying proportions of the constituent 
parts, but they usually contain mineral substances 
and from eight to twenty per cent of humns. The 
humus soils absorb and preserve moisture, and old 
shrubs usually thrive on them and produce a rich 
foliage. Young plants, however, easily fade and perish, 
and seeds do not develop, but rot. 
The clay soils are of a brown hue, and are usually 
composed of fine clay and from ten to fifteen per cent 
of the oxide of iron, with some proportion of sand. 
These soils are arid, and during the rains absorb 
much water, drying up to the depth of two or three 
feet immediately afterwards, and also becoming heated. 
Here the tea-shrubs do not thrive except in moist 
seasons. 
From I869 to 1873, the shrubs in the humus soils 
were always affected by blight, which first attacked 
the leaves and the best' developed shrubs in the beat 
parts of the garden, also the shrubs in the alluvial 
portion lying at the base of or between the hills. 
The shrubs in the red soils were at first free from 
blight, but they were also attacked when the fine 
leaves on the shrubs in the humus soils had been des- 
troyed. Several experiments were then undertaken in 
order to ascertain the cause. Where the humus was 
thin or absent, the roots of the shrubs were top- 
dressed with good earth, which led to a new flush 
that was again attacked and destroyed by the blight. 
A very fertile part of the plantation was dug to a 
depth of 18 inches and thoroughly cleaned ; in 
another place, furrows to the same depth were made 
and filled with branches of other trees; again another 
patch was drained ; in another sticks smeared with 
tar and oleum cornu cervi fmtidum. were placed 
amongst the shrubs ; tar was also put in the ground ; 
hut none of these experiments proved suc- 
cessful. Large quantities of calcium suXfuratum were 
also placed on the ground, and in another part freshly 
made phosphates, but the rust did not diminish. 
Fumigation with sulphur burned to windward only 
resulted in the destruction of the leaves’‘reached by 
it ; whilst fumigation by burning bad-smelling wood 
and leaves to windward had no influence at all, 
Pruning only gave temporary relief, and when potatoes 
were planted in the neighbourhood of affected shrubs, 
they also blackened and died. 
Picking off the insects as they appear has 
been recommended and tried. When it is con- 
sidered that if only moderately bad there are ten to 
twenty insects on each bush and if very bad thirty 
to forty, and the shrubs are planted 6' x 3' the 
number of insects to an acre — and therefore the num- 
bers in a considerable garden — will preclude recourse 
being had to this procedure on an extensive scale. 
The insects are most injurious in the larval state, 
even when they are of miscroscopic dimensions, and 
when disturbed, however slightly, drop through the 
bush to the ground, where it would be useless to 
followthera. Picking would therefore bo too expensive 
and unsatisfactory, as only partially clearing the bushes. 
In this connection Dr. Aleyboom recommends the 
early plucking of tips and tender leaves, so as to 
diminish the food-supply of the insects, which as 
already noted, attack those parts first. Another sug- 
gestion that cannot be recommended is to place bird- 
limed strings or light cotton bag.s smeared with some 
similar sticky substance in the affected area”. 
Syringing as a prophylactic would be of little use 
iu the rains, as in a day of heavy rain the snt» 
stance ns.-tl wnnld be wisher] awa,y. SnraTing infected 
tii'S ■win n the attacks first appear willi kcrosine 
(fniilsion as an insecticide appears to prornise pood 
I' U ’ . ft baa been of practica! value in the case 
of coccid pests on coffee, and is very simply made, 
j 'I’ho proper course suggested by the life-histoTV of 
the insects i.s to search for the eggs, and to spray 
I tbo'c 71I11CCS where they occur, for, us a rule, in the 
I earliest stages, the Iarv;o are found ouly where the 
1 eggs have been deposited, * • ♦ 
Amongst the many remedies proposed, cutting down 
the forest and grass jungle adjoinmg plantations has 
found some favour. A writer in the Calcutta .leurnal 
already quoted suggests that toon trees mav harbour 
the insect fNovemher 18851, another that spear grass 
spd other similar growths furnish the shelter. There 
is no dcubt that in this country grass harbours vast 
numbers of Ctpsidm. and it is quite possible that the 
original food-plant of the insect may be discovered and 
eradicated. It is, however, for the planters themselves 
to discover this, and there can be no harm in removing 
and burning during the cold weather grass junglein the 
neighbourhoodbf plantations. Some support is given to 
this remedvby the statement of a planter that ■' even 
if destroyed on the tea plants, the insects come m 
from the neighbouring iungle, which should be burned 
down.” Others sav fjourn., 1. c.. vii, p. xlii) that 
clearipg the jungle is of no value. There is no precise 
record, however, in the whole of the correspcncleree 
regarding this pest of the persenco of the insect on 
any plant other than tea or cinchona. 
[This Ilelopeltis seems to be as specially^ and 
exclusively a tea pest, as Hemileia vnstatfix is 
exclusively a coffee parasite. — Ed. T. A-I 
Anointing the bu.sbes with “tar” has been re- 
commended and tried, but abandoned, as it flavours 
the tea. Fumigation by burning bad-sm”lHng weeds 
is reported in some cases to bnve kept down the 
pest, “but to do this successfully, the tila surround- 
ings where thev harbour and breed must be cleared 
away and burned during the cold weather.’ 
Mr. E. B. Walker, Manager, Sookerating Tea 
j^state. Doom Dooma. Dibrugurh, writes ; — 
Now to reply to vonr inquiries about what we 
did to get rid of the ‘ Mosquitoes.’ To begin with, 
before we stopped p’ncking last year, and while <he 
blight was at its worst ("about September and Octo- 
ber), I started cutting down a ‘beH’ of jungle 80 
yards wide all round the edge of the garden; this 
‘belt’ was completed about the same time as the 
pruning of the garden was finished (the end of 
February this was): well then I commenced light- 
ing fires a'l over the place : in the tea, the pru- 
nings were being redueed to ashes as rapidlv as the 
cut-down jungle in the ‘belt’ w»s being burnt up; 
by the middle of March I finished al’ the burping 
I wanted to do. and then every soul was pu*” on to 
hoe round the bushes, take aicay oil stale earth from 
near the stumps of the plants, and fill in fresh earth. 
The pruning I went in W last cold weather was most 
severe.' the whole of the garden nearly was cut down 
to within eight inches of the ground: all knotty and 
gnarled wood was removed and nothing hut straight 
wood left. During the pruning, immediatelv following 
up the primers were gangs of women and children armed 
with small knives whose only work was to rid the hushes 
o f every leaf and small twia. To protect the plants from 
the flames (while the prunings were being burnt) a drain 
fifteen inches deep by a foot wide was made^ in every 
alrernate row of tea, and into this the pruning leaves, 
A'c., from round about were carefully brushed before 
being set alight to. 
“ Up to date not a trace of the blight is to be seen ; 
this time last year about ICO aoma (or more) were 
completely mined ; the tea is looking as healthy anfl 
nine, and growth is as vigorous as though the plants 
bar! never been blighted. So successful have we been 
so far in combating this destructive pest, that I am 
convinced now we will not be troubled with it at 
all this season, and that we will make oiir 8 to 8) 
maunds an acre against a miserable 1 maunds an acre 
last season ! 
“The theorv of letting te.a run baa been tried 
without the slightest signs of doing nnv'good, for the 
simple reason the hushes can't and wont run! Bushes 
that I left alone during the three months (middle of 
April to '-dddlo of ,Iuly) were, if anything, smallev at end 
of this period than at commencement of ,it, because 
not a vestige of growth had been made during the 
whole of this time, and the long healthy shoots chiefly) 
in the very centre, therefore the tallest part of the 
