Knowing what’s in your soil helps you……..
- Save money.
- Protect water quality.
- Grow better crops.
You need nitrogen to turn those Average Joe crops into
top-notch superstars that return high yields.
Now, If it was only as simple as applying any ol’ amount of nitrogen
fertilizer to your crops, you’d be hitting homeruns over the fence for every
harvest. However, nitrogen sometimes plays in a different game, ignoring play
calls and throwing curve balls at your growing season.
N makes up a very active member of your team. Nitrogen is a tricky nutrient for growers to
manage because it’s always changing.
Sometimes it’s in the proteins of organic matter. And sometimes it’s broken down into simpler
‘available’ forms, like ammonium and nitrate.
From there, it may leach out of soils or be taken up by plants or
microbes, where it becomes part of organic matter again.
To complicate things further, the
total amount of nitrogen in the soil continuously changes. In addition to leaching loss, nitrogen can
also evaporate, or volatilize, when soils are wet. Or, in some cases, you may end up with more
nitrogen in the soil. Soybean (legume) roots add it to the soil by fixing it
from the air. Compost, manure, or fertilizer also increase nitrogen levels in
the soil. And even nature plays a role in increased amounts of nitrogen if
organic residues build up over time, increasing the levels of organic matter in
the soil.
Mineralization Matters
The release of available nitrogen
from decaying plants, compost, manure, or soil organic matter is called
mineralization. Think of this process as lunch for soil microbes with poor
manners. The microbes gobble up those materials then spit out any extra
nitrogen they don’t need to build their bodies.
One of the largest impacts on the
rate of mineralization is environmental conditions. Microbes tend to be
especially active and eat more when the soil is warm and moist and sleepy if
it’s cold and dry. Kind of like a bear in hibernation.
How Does SoilSens Fit In?
SoilSens is like the coach on your
team. It measures the amount of nitrate nitrogen that is available in the soil,
providing information so you can help your crops perform at their best. It calls in the help of one of the team’s
most important players—water. Obviously,
crops need water, regardless of how fertile the soil is, or they’ll die from
starvation. Water serves as the transfer mechanism—the super highway that
carries the nitrate ions to the plant—for the fuel source. As they’re carried along this super highway, nitrate
ions are absorbed into the plant’s roots.
SoilSens utilizes this natural
process, mixing soil samples with deionized water, to measure the nitrate ions
transferred from your soil into the soil slurry mixture.
The significance of knowing the
amount of nitrate nitrogen currently available allows you to fine-tune your
nitrogen fertilizer applications, making sure the crop has what it needs without
wasting money over-applying fertilizer or potentially threatening the water
quality.
Measuring Nitrate Ion Levels
While measuring soil nitrate ion
levels is a time-tested way of measuring soil quality, it has not been
traditionally used by soil laboratories.
Soil laboratories normally use a method called KCI Extraction/Cd-Reduction. Essentially they extract the nitrate from the
soil, mix it with a chemical that changes color in relation to how much nitrate
is present, and then measure the color change.
The method has the advantage that it is easy to automate in a lab
environment. It has the downside of
using Cadmium, which is a hazardous material.
It also requires the soil to be dried, which can cause significant
changes in the soil nitrate contents.
While SoilSens has the advantage
of using field fresh soil and being portable, it does not have the same
established history as the lab tests.
Therefore, interpreting SoilSens results will differ from traditional
lab results. Below is a guide that shows
how to interpret SoilSens results:
SoilSens Test Results Interpretation
Less than 3 ppm Very likely N
deficient, side dress N is recommended.
4-10 ppm Low, but may be
sufficient for a medium-yielding corn crop.
10-20 ppm Sufficient N is available for most crops. For highest yields,
10-20 ppm Sufficient N is available for most crops. For highest yields,
