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Items
found on the test report include:
Sample
Location -The name of the area from which the sample was taken
(pasture 1; Field 2; Plot 4; etc.)
Sample Identification-The name
of each particular sample taken from the designated field or pasture,
(A, B, C1, 2, etc.).
Lab No. - This is the number
assigned to the sample by the Laboratory.
Total Exchange Capacity
(M.E.)- The TEC represents the measured capacity of the colloidal complex
of each soil sample to adsorb available base (positively charged elements)
nutrients for plant feeding. It
provides the index for corrective treatments to establish proper balance
of nutrients in the soil. It is expressed in milli-equivalents (M.E.) per
100 grams of soil.
pH - The pH indicates the
active hydrogen concentration in the soil solution. This
value can indicate if a soil is under or over limed.The percent Calcium
and Magnesium saturation, the crop and the soil pH suggest the kind and
the amount of lime a soil needs.An ideal pH for most crops and soils would
be between 6.2 and 6.8 (1:1 soil to water ratio).
Buffer pH - This test allows
for the actual reading of the exchangeable hydrogen that is present in the
soil. A know amount of a base (liming material) is added to get the
results. This makes it easier
to get a good recommendation as to lime requirements of a soil.
Organic
Matter (humus) %- This percent represents the amount of readily
oxidizable humus in a soil. Only the active portion of the soil organic
matter (humus) is reported by loss on ignition test.
Estimated Nitrogen Release -
This number is a computed estimate of the amount of Nitrogen that may be
released annually from a soil through organic matter decomposition. Most
of the reported Nitrogen will be released in the late spring and summer
months with a smaller amount during fall.
Soluble Sulfur - S
ppm (parts per million) this is soluble sulfur extracted from the
soil.Ideal sulfur ranges, depending upon soil total exchange capacity,
will vary from 15 to 35 ppm. Some
situations may call for higher sulfur levels.
Phosphates - Two Phosphate
values are usually reported on most soil analysis.The first is Easily
Extractable-P and the second is Bray ll-P.The easily extractable-P ranges
from 140 lbs/acre to over 200 lbs/acre, but depends on crops being
grown.The Bray ll-Phosphorus represents that P that is plant available and
about 10-15% of the unavailable phosphorus.This test was designed to
detect a portion of the rock phosphorus that is present in a soil.The
ideal levels range from 200 to 450 lbs/acre.
Calcium - This number
represents the extractable that is either adsorbed on the soil colloid or
is in the soil solution.This is perhaps the most important element within
the soil because of its effect on the availability of all the other
nutrients.It is the most abundant element in the soil.
Magnesium - This number
represents the extractable magnesium that is absorbed on the soil colloids
or that is in the soil solution.A minimum of 200 lbs/acre is desired on
most soils. Excesses often exist in
many soils, particularly soils that have a lot of clay in them.It is
probably the second most abundant element in the soil.
Potassium - This number
represents the extractable potassium adsorbed on the soil colloids or in
the soil solution. The ideal
level of potassium varies with the Total Exchange Capacity and the crop
being grown.
Sodium - This number
represents the extractable sodium adsorbed on the soil colloids or in the
soil solution.Sodium is not considered to be a plant food nutrient but is
very important in the overall balance of nutrients in a soil.High sodium
levels will negatively effect drainage and upset the balance of nutrients
because the pH will adversely increase.Ideal sodium levels will be under
100 lbs/acre in most soils.
Base Saturation Percent - This
number represents the portion of the soils nutrient holding capacity
(Total Exchange Capacity) that is occupied by each of the base elements
Calcium, Magnesium, Potassium, Sodium and Hydrogen (and other bases on
some analysis).Most soils growing most crops should have a combined
percentage of Calcium and Magnesium around 80% Base saturation with
Calcium being around 65% to 70% and Magnesium around 12% to 15%.
Potassium may vary from 2% to 6% or 7% depending on the soil and
the crop being grown.Sodium is usually under 2% and most soils less than
1%.Hydrogen Base Saturation will vary as the pH varies in the soil.
Ideal saturation would be 4% to 12%.
Higher Hydrogen saturations will indicate extremely low pH and show
the need for a limestone application.Soils that show 0% Hydrogen
saturation are soils that have very high pH (over 7 pH).
Other Bases - On test packages
that include Other Bases will
give a saturation percentage that is a calculated estimate of the combined
base elements or cations (excluding Calcium, Magnesium, Potassium, Sodium
and Hydrogen) which are considered being in the soil.As the soil pH drops,
the percentage of these becomes more active and the level will increase.
Such elements as Manganese, Copper, Aluminum, Iron, Barium,
Ammonium, zinc, etc. are included in this category.
Exchangeable hydrogen - This
number represents the percent Hydrogen found in each soil.
It indicates the degree of acidity present in each sample.As soil
pH decreases, the amount of Hydrogen will increase.Soil with a pH above 7
will generally show no exchangeable Hydrogen.
Boron-
This is expressed in parts per million and not lbs/acre because it is
present in very small amounts in most soils.Boron ranges from .2 ppm to 5
ppm with an ideal reading from .7 ppm to 1.5 ppm.Boron is an anion and is
soluble and will therefore leach out over time.
Iron-
Is expressed in ppm.Most soils have an adequate supply of Iron for crop
production.As soil pH rises, the availability of Iron will decrease and
plants exhibit chlorosis.Iron is necessary for the proper functioning of
chlorophyll in the plant.
Manganese - Is expressed in
ppm. Soil acidity (low pH) increases Manganese availability and it can
become toxic at extremely low pH. Very
high pH will cause a deficiency of Manganese.Soils will range from 10 ppm
to 400 ppm of Manganese with ideal levels around 40 ppm or higher.
Copper - Is expressed in ppm.
Copper is likely to be low in soils that have very high organic
matter levels. Copper is held very tightly by the soil colloids and is not
very soluble or mobile. High pH decreases copper availability.It is used
by plants to metabolize both carbohydrates and nitrogen.
Zinc - Is expressed in
ppm.High soil pH will decrease the availability of Zinc. Most
Zinc is in some organic form in the soil.It is used by plants to increase
growth rate as well as giving the plant longer stems and bigger
leaves.Soils with very high Phosphorus levels will often exhibit Zinc
deficiencies.
Aluminum - Is expressed in
ppm.Aluminum is not a plant food nutrient but plays a major role in the
availability of several other nutrients.As Aluminum levels increase,
Phosphorus can be negatively affected.High Aluminum also takes up space on
the soil colloids and prevents other elements from being there.The
lower the level of Aluminum in the soil, the better the soil is.
Levels will range from 200 to several thousand ppm.
Cobalt, Molybdenum, Selenium,
Chlorine - Are all expressed as ppm.These are essential nutrients but
soils are not often analyzed for them except in special situations where
all other elements seem to be at appropriate levels.
They are rather expensive tests to run but can and will be done
when deemed necessary to produce desired results in crops
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