t'EB. 1, 1899.] Supplement to the " Tropical Agriculturist" 59^3 
vetcl). The effect of chicory in keeping open peat 
or clay land, and for so preventing it from solidify- 
ing, was particularly called to my attention by 
Dr. Voelcker when lie was lately inspecting the 
field in which, two years ago, we traced the down- 
ward course of chicory and burnet roots right 
through a very hard grass into the soft subsoil — 
the field, I may add, which was described in my 
paper on " The Value of Plant Eoots as Tillers of 
.the Soil'' ("Eoyal Agricultural Society cf 
England's Journal," September, 1897). And the 
result of thus opening, and keeping open, the soil 
■with the agency of deep-rooting plants is, of course, 
remarkably ai)pnrent as regards the grass, the 
result being that whereas in the case of an adjacent 
field on the same flat the land is baked as hard as 
pavement, and the grasses are quite dried up, the 
field alluded to is quite green, and, comparatively 
tpeaking, soft — so much so that my friend cut up 
with his pocket-knife sections of the soil — sections 
with a chicory plant in each — to show m« how 
the powerful chicory laterel roots had kept the 
soil open and pliable. This field, I may observe, 
is particularly valuable as an illustration, as it had 
been laid down by me to permanent pasture before 
I had ascertained the use of these deep-rooting 
plants, and in consequence of its comparative 
failure (owing to the hard grass) was ploughed up, 
and again laid down in April, 1895, and thi.s time 
with complete success. Those of your readers 
who are interested in this important subject may 
read with advantage Mr. Rider Haggaras's pa{.er 
in the September number of " Longman's Maga- 
zine." When laying down land to permanent 
pasture he selected his worst field for an experi- 
ment on my system — that is, with the addition of 
chicory, burnet, &c., and now he finds that his 
worst field has beaten the best. 
" In conclusion, I may note that the advantages 
of using a mixture of the most drouglit-resisting 
and deep-rooting plants and grasses in the case of 
land to lie for four or more years by no means 
terminate with the fact that keep for a stock is 
more plentiful and reliable, for when you plough 
up a thick sod composed of deeply-rooting plants, 
which have not only cultivated the land to the 
utmost depth, but charged it deeply with vege- 
table matter, you obtain belter grain and turnip 
crops, and enable both to resist drought in really 
an astonishing degree — facts which have been 
amply proved this year on my Clifton-ou-Bowmont 
farm." 
SOIL MOISTURE. 
Under this heading Mr. F. B. Guthire contri- 
buties some thoughtful notes. Ilis object in 
writing, he states, is to present some information 
as to what Is known about the causes of loss of 
•Vvater in the soil, and the means by which this 
loss may be prevented or to some extent delayed. 
For, says he, though we are powerless against 
drought, we should be able to adopt certain 
remedial measures in alleviating the effects of a 
long spell of dry weather, and it often happens that 
the crop might have been saved if it could have 
held out a low days longer. Moisture is lost from 
the soil in two ways, by drainage and by evapora- 
(iou. 
All soils have a certain retentive power, for 
water which enables them to resist to a greater or 
less degree these two causes of loss. 'J'his power 
IS largely dependent on the texture of the soil 
and is highest in peaty soils, and soils rich in 
humus followed in order by marls, clays, loams, 
and sand. 
The loss due to drainage is liable '.o be exagger- 
ated, indeed there is no room for doubt that 
pro])erly-drained soils are much less liable to 
suffer from drought than undrained soils. 
The action of drainage does not come into play 
until the soil has absorbed all the water which it 
is capable of taking. 
Drainage only removes the surplus water. In 
the case of a fine soil lying on a coarser stratum, 
a condition under which the natural drainage is 
most effective, it is a fact that the fine soil does 
not part with its water to the coarser soil below 
until it has itself taken upas much asiit will hold. 
When we further remember that in a well- 
drained soil the conditions favourable to fertility 
are at their maximum, that its capillary power 
is increased, and it is enabled to absorb moisture 
and dew on its surface, and to draw up water 
from the lower strata, and that in such a soil 
the roots of the crop have free development, and 
can penetrate to a greater depth in search of 
moisture than on badly-drained soil, it is clear 
that the soil does not lose much of its es.'^entiai 
water by drainage, and that a well-drained soil 
is in point of fact in a belter position to resist 
drought than an undrained one. 
Tlie chief loss due to drainage is the loss of 
soluble fertilising material, especially nitrates, 
but this occurs principally during the summer 
and early autumn, and theti only when the 
rfiinfall is fairly abundant. In dry seasons loss 
from this cause may be neglected. 
The principal cause of the drying up of ,<:oils 
during dry weather is evaporation. 
AVater evaporates from the soil in two ways, 
from the surface of the soil itself, and from the 
leaves of the crop. 
The loss of water by transpiration is enormous, 
far greater than would be generally believed. 
Experiments have shown that a crop of barley 
during its growth evaporates nearly 9 inches 
more water than is evaporated from an adjoining 
field under bare fallow. 
Transpiration is, of course, beneficial, and a 
vigorous crop evaporates more water than a sickly 
one. The water thus exhaled by the leaves is 
continually replaced by water absorbed by the 
roots. When the plant is unable to obtain 
sufficient water through its roots to replace the 
water lost by evaporation through the leaves the 
plant begins to wither. 
This transpiration may be, however, reduced to 
a minimum without detriment to the plant, and 
does not appear to be an absolute essential to ita 
growth. The ammint of water evaporated from 
an acre of wheat during the si.x months of ita 
growth has been cnlculated to be 3J millions of 
pounds (this includes the evaporation both from 
leaves and soil). This (puiiitity represents the 
t-^i nl amount of water received per acre during 
tlie whole year when the rainlall is about 17 
iuchea* 
