118 COFFEE CULTIVATION AND MANURING. 
grows older and fills the surface soil with its feed- 
ing rootlets to a greater extent and distanee. Then 
most of the growth of the tree is carried on through 
these large horizontal roots, but the tree seems rather 
to seek it farther down. The reason of all this is, 
I think, because only on the surface is there nourish- 
ment for the roots to find.* Many planters who have 
made vegetable gardens, or even coffee nurseries, 
must be well aware of the badness of our soil, gener- 
ally, at the depth of a few inches. They must have 
found that their deep digging, and mixing the soil, 
spoiled their garden, and that in spite of heavy 
manuring things would not grow for them at all to 
compare with what their coolies grow in their gardens 
without manure, and by simply scratching the ground 
on the surface. Our sub-soils are not by any means 
easily or soon improved, either, and the first inch 
of the surface is the best. 
Of course, putting manure on the surface i+ may 
be expected to act sooner, and often will, as the 
feeding roots are there ready to make use of it. But 
much depends on the kind of manure, and much on 
the nature of the soil. I have found coffee pulp put 
on the surface, or even shallow holes and_ slightly 
covered, have very little effect, whereas in the same 
place when put in good holes and well covered no 
_ manure surpasses it. Earthy rubbish from the cooly 
lines I have found have the best effect when put on 
the surface, but it is usually so full of seeds as to 
make the weeding expensive on a clean estate. I 
would not think of putting manure very deep into a 
bad sub-soil in any case, nor of digging either manure 
or water holes into a retentive sub-soil in which they 
would retain stagnant pools of water. 
I think water holes would be quite likely to cause 
wash unless they are effective always in holding all 
the water till it percolates away. A moderate quan- 
tity of water will run pretty clean off an old exposed 
surface which would run thick mud off freshly turned- 
up soil.. Then water running out of water holes would 
run out in considerable rills, instead of being evenly 
spread. To cut a large hole at all, in steep ground, 
necessitates a high bank on the upper side which the 
trees will look perched on the top off. Drains should 
be steeper, the more steep the ground is, as more 
earth and stones are apt to get tumbled into them, 
and small slips of the upper bank are apt to choke 
them. A drain choked up in a heavy shower is most 
mischievous. The water collected is all turned out at 
one spot, and ruts up the ground down to the next 
* Coffee roots seem also to like a loose-open soil. 
— 
