32

ne sc

All soils ars mixtures of these seven crade
in varying proportions. . 3

—menenthiaiceaeati eee

[exes ty << *

The following gives the different general ¢ 2
of soils: : a si

Peats < Consisting of 25 per cent or more of organic
metter, sometimes mixed with more or less
sarmé or silte

Mucks « Soils with fifteen to thirty-five per cent of
partly decomposed organic matter mixed with
much clay and silt.

Clays = Soils with more than thirty per cent clay
usually mixed with mach silt.

Clay loam Soils with from twenty to thirty per cent clay,
usuzily mixed with much silt ana some sande

Losms = Soiis with thirty to fifty per cent of sand
mixed with mich silt and a little clay.

Sandy LoamseSoils with fifty to eighty per cent of send,
mixed with silt and clay.

Fine sanéy loams + Soils with fifty per cent or more of
ope send mixed with much silt ang a little
elaye

sand = Soils with more than eighty per cent of sand.
Graveis = Soils with more than fifty per cent grevel.

Roek outerops = Usually ledges of rock having no direct
agricultural values

Mere or less organic matter is found in all
the above groupse

Supply and Liberation of plent food. = {

The productive capacity of land im humic sec- |
tions dspends almost wholly upon the power of the soil
te feed the crap; and this, in turn, depends both upon
the stock of plant food contained in the soil and upon
the rate at which it is liberated, or rendered soluble
ané eveilable for use in plant growth. Protection from
weeds, insects, end funges diseases, though exceedingly
important, is not a positive but a negative factor in
erop producticne

The chemical analysis of the seil gives the
inyoice of fertility present in the soil strate sampled
an@ analysed but the rate of liberation is governed by
many factors, some of which may be controlled by the
farmer, while others are largely beyonce his control.
Chief among the important controllable factors which .
inflmence the Liberation of plant food are Limestone 1
ané dseaying organic matter which may be added to the
soil by direct application of ground Limestone and farm
manuree Organic matter may be supplied aise by green=
mamure crops and crops residues. ‘The rate of decay of
organic matter depends largely upon its age and origin