Agriculture Reference
In-Depth Information
Essential Primary, Secondary, and Micro Elements
Primary Elements
Needed in large amounts
in soil
Secondary Elements
Needed in lesser amounts
in soil
Micro Elements
Needed in very small amounts
in soil
Anions
Anions
Cobalt Co
Selenium Se
Molybdenum Mo
Nickel Ni
Vanadium V
Chromium Cr
Yttrium Yt
Cesium Cs
Strontium Sr
Fluorine Fl
Iodine I
Titanium Ti
Lanthanum La
Cerium Ce
….and many more
Sulfur S
Phosphorus P
Nitrate NO
3
-
*
Boron B
Chlorine Cl
Silicon Si
Cations
Cations
Calcium Ca
Magnesium Mg
Potassium K
Ammonium NH
4+
*
Sodium Na
Iron Fe
Manganese Mn
Copper Cu
Zinc Zn
.
(*Amolecule, not an element)
To the left is an
illustration of Justus von
Liebig's “Law of the
Minimum” showing
most of the factors that
limit growth, from light
to heat to soil minerals
and air. Nitrogen is the
short stave, the limiting
factor, in the barrel on
the left. The barrel on
the right shows Nitrogen
brought up to the
desired level; now
Potassium is the limiting
factor. It can truly be said that all of the essential elements are equally important.
Whichever one is in shortest supply will limit the health and growth of the entire
organism.
Figure 1: Liebig's Law of the Minimum showing most of the factors that
can limit the growth of crops.
