This is provided by theeasily erodible loess soils
of the upper reaches of the catchment area.
The first indication of the condition is a
darkening ofthe foliage and the slowing down of growth.
There is, of course, no single anti-erosiondevice
which can be universally adopted.
The protection of the crop from the inroads of the
parasite.
Development andActivities of Crop Plants,
Publication No. For many years erosion control measures have formed animportant item
in the national budget.
Accumulations of organic matter such asoccur in
temperate zones are impossible.
Ifsufficient water is available it is sometimes
possible to reclaim alkalisoils by washing only.
These follow theusual methods of quarantine.
Theresources of the Government are being called up to put the land
inorder.
These quarantine methods therefore cannever
succeed. An impressive volumeof specialist literature has resulted. Grass is a
valuable factor in the correct design and construction ofsurface
drains.
Nevertheless, certain guiding principlesexist which
apply everywhere.
Originally well wooded, noforests are to be found
in the Mediterranean region proper.
Theodore Roosevelt first warned the country as to
itsnational importance.
It is exceedinglyeasy under canal irrigation to
create alkali salts on certain areas. More than fifty years have passed since the
modern work on the diseasesof plants first began.
More than fifty years have passed since the modern
work on the diseasesof plants first began.
InNorth Africa the fertile cornfields, which
existed in Roman times, arenow desert.
The grassis thereby automatically manured and
yields abundant fodder.
The slow rotting of exposed rock surfaces is only
one of the forms ofdecay. In this way water can be provided without anyinterference
with soil aeration.