My garden soil in Jacksonville, OR is heavy clay that dries out and becomes
hard and water resistant during summer. Water can puddle on the surface, but
if the soil is scratched, it is bone dry a quarter of an inch below, and
plants would die of drought in spite of frequent watering.
I found by experiment that if ammonium sulphate is sprinkled on the clay and
watered, it gradually sinks in, and when enough is applied, the clay becomes
soft, crumbly and permeable to any desired depth. Plants that previously had
wilted now grow well in it. Clay soil in the Sunland - Tujunga area of SoCal
has been found to respond in the same way.
No reference to this effect has been found in garden books or on the
Internet, and no gardeners of my acquaintance are familiar with it. So I do
not know if this works for all clays, or if it is a fortunate fluke of the
I would appreciate hearing from anyone who might be interested in trying
Il 2010-02-17 06:01, Desmond Armstrong ha scritto:
This is the typical beauvoir of clay soils. You can improve them by
means of organic mater and/or bivalent cations like Ca++ (from lime), or
Mg2+. Cations endowed of 2 positive charges create a bridge between two
clay molecules and allow many molecules aggregate and create flakes with
spaces among clay clots. By this way air and water can move through the
clay particles to the plant roots.
Monovalent cations like NH4+ (ammonium), or Na+ (Sodium) can't create
any bridge-bound between clay particles, but they can only saturate the
clay's negative charges, make them precipitate in the soil solution.,
making the soli more compact.
What could have happened to your plants is that SO4- (solforic) ione
reacting with Na+ (frequently stored over the soil surface in hot
climates), has generated Na2SO4 and then water can have taken it away.
Salts when stored on the soil surface can prevent water enter the plant
In that case your problem could be a salt soil, instead of the clay
ratio. All this can explain the effect of ammonium sulphate, cause of
the sulphate, that reduce pH in alcaline soils making them more acidic.
I hope this helps,
Yea, you and Janice Bailes and how many of your other classmates at
Lansing Community College?
So this is what passes for higher education in the US these days?
You get marks for making garbage posts to usenet?
And you people don't even know what usenet is. You think this is some
kind of blog.
Read the following two patents:
Method for the manufacture of soil modifiers from waste materials of the
manufacture of titanium dioxide
invention relates to a method for the manufacture of soil
modifiers,highly active on compact soils and easy and economical to
apply, from the waste materials consisting essentially of ferrous
sulphate heptahydrate, obtained in the manufacture of titanium dioxide
by the sulphate process.
As is known, many of the world's countries have vast areas of very
compact soil, especially clay soils, little suitable for cultivation.
In these soils the structure is such that the composition of particles
practically prohibits the circulation of air and water and consequently
also the passage of salts from the surface to the root system of the
In such soils water penetrates very slowly, causing expansion of the
clay particles which induces closure of the pores or prevents further
ingress of water, passage of salts, and circulation of air.
On the other hand during the dry season, water present in these soils,
owing to the continuous capillary channels which are always
characteristic of hard clay soils, works to the surface carrying with
it, also, the salts dissolved in it.
These soils thus come to assume the state of dryness which gives rise to
deep cracks and cementing of the clay particles into a hard and
Under these conditions the life cycle becomes difficult, not only
because of insufficient presence of water and insufficient aeration, but
also because of the high concentration of salts near the surface.
In methods for modifying the characteristics of compact soils,
especially clay soils, so as to render them suitable for cultivation,
recourse is frequently made to the application of salts, usually ferric,
such as ferric-ammonium alum and ferricsulphate.
These salts induce agglometation of the minute clay particles into
granules, with appreciable improvement in the permeability and aeration
of the said soil. Moreover, a porous granular structure diminishes the
dangers of scouring and soilerosion.
Process for the preparation of fertilizers and soil modifiers
solid thus obtained, consisting mainly of ferric hydroxide and of a
lesser amount of ammonium sulphate, may be used directly as a soil
modifier with the additional function of fertilizer.
The compositions thus obtained may be used especially as modifiers of
compact soils, particularly alkaline clayey soils, with the additional
fertilizing function on account of the presence of ammonium sulphate.
In these soils, which are very widespread and are barely suitable for
cultivation, the structure is such as to render the circulation of air
and of water practically impossible due to the arrangement of the soil
It is already known in the art that in order to modify the
characteristics of compact soils, particularly clayey ones, in order to
render them suitable for cultivation, it is possible to resort to the
application of ferric salts to the said soils. These salts cause the
agglomeration of the minute clayey particles in the form of granules
which give the soil a porous granular structure.
This structure improves the permeability and aeration of the soil, in
that the water and the air can thus readily penetrate into the free
spaces between the individual granules of the soil, with great
advantages for the crops.
Ok smart ass. Just how much do you and your classmates at LCC want to
screw around here?
If you keep doing it, I'm going call your mom (Sharon) and tell her that
you're being a weenie.
And yes, I know your phone number. It's (517) 646-86xx.
Thanks to Lawn Guy and Lancilotto del lago for your comments.
Calcium sulphate has long been the clay modifier of choice, but because of
its low water solubility it is preferably tilled into the soil before
planting. It appears that ammonium sulphate is most suitable for use in
existing plantings, as it can be scratched into the surface, and water takes
it down into the soil. Of course, if there is too much, root absorption is
My guess is that the NH4+ ion does not persist for long in the soil, since
it is absorbed by plants, or is eventually converted to nitric acid by soil
organisms. Then the net effect of ammonium sulphate would be to acidify the
soil and increase the sulphate concentration.
It will be necessary to determine whether the observed clay modification is
a temporary or permanent effect.
Soil improvement is also applied to improve the mechanical
characteristics of contaminated soft soil by immobilising heavy metals
and other soil contaminants. Many techniques have been developed to
consolidate contaminated sediments such as dewatering the sediment to
reduce the quantity of soil, or combining the sediment with additives,
such as mixing sediment with cement which allows the recycle use of the
sediment as construction and/or reclamation material.