Nutrient Cycles
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A "cycle" is defined as "as a series of events which repeats regularly". All nutrients operate in cycles, either depleting or building up in the soil. A nutrient which is building up is what TSM_® calls an "up cycle" and a nutrient depleting in the soil is called a "down cycle"..
 

Now let's use some "common sense".

If you apply a nutrient through applied fertilizer and you take a soil test,  would you expect the soil test to?
(the questions may get harder as we go along!)

Go up?
Go down?

The answer is, "Go up!"
 

This starts the "up cycle" which will continue to go up until the applied fertilizer is used up.
 

If you did not apply any more fertilizer and the nutrient was used up, what would you expect the soil test to do?

Go up?
Go down?

The answer is, "Go down"

So much of agronomy is just good common sense, yet we don't use it.
Let me give you an example.
When you are in an "up cycle", you have greater fertilizer effeciency than when you are in a "down cycle".
"Down cycles" have a very poor effeciency.
it takes product to "stop the down cycle"
it takes product to "turn the cycle" around
before your soil test will change

Keep the cycles "short" (better quality product) and "flat" (small and regulate amount)
Fertilizing every year for every crop will help do this!

For more information, place your cursor on TSM Soil Fertility" (column to your left)
then click on "Fertilizer Efficiency" from the drop down list
 

To identify cycles, take soil samples OFTEN!
 

TSM_® takes soil samples annually so we can determine what cycle the nutrient is on. As soon as you take the second soil test, you will see the cycle forming. On the chart below, an "up cycle" is represented by the "blue arrow". The "down cycle" is represented by the "red" arrow.

The effeciency of the fertilizer applied is greatly determined by what cycle the nutrient is on.
 

If a nutrient is on an "up cycle", you can expect a high nutrient effeciency perhaps up to as high as +400%.

If a nutrient is on a "down cycle", you can expect a very poor effeciency perhaps as low as -400%.


Now here is some more "common sense".
On an "up cycle", you should reduce the amount of fertilizer you apply
On a "down cycle", you need to increase the amount of fertilizer you apply


When you are using the Total Soil Management_® soils programs, it does this automatically!!


Soil pH also has a cycle and is the easiest to follow. For example, on a "down cycle", it is possible to make an application of ag lime or pelletized lime (powdered lime granulated), then soil test and the pH has gone down. This possible because there evidently wasn't enough lime applied to stop and turn around this cycle. It could be very misleading unless you knew you had a "down cycle". 

On the other hand, the opposite could also happen. An application of ag lime or pelletized lime could be made and the pH "jump" much more than normally expected. This would indicate an "up cycle" is taking place with calcium and/or magnesium.
 

When you don't soil test often enough to control cycles, cycles can only be determined after they happen!
But because you don't soil test often enough, you don't even know you have them!!
Then you "live with them" instead of "controlling them".
 

A pH cycle is determined by two factors:

* The amount of the ag lime product applied
* The quality of the ag lime product applied 

The ideal way to control pH cycles is to use both pelletized lime and ag lime together.


Using high quality, finely ground liming material in larger amounts will cause a very fast "up cycle", but it is very short lived. This works well where you are wanting to change pH on an annual basis.

Using poor quality, coarse liming materials causes a very slow "up cycle" , but it may last for many years.

Your liming program should be made up of both "short term" (pelletized lime) and "long term" (Ag lime) products.

Question: "If you take a soil test and your pH is 6.0, is this on an "up cycle" or "down cycle"?

Answer: You can not tell. You have to have two soil tests within five years of each other.

 

Since TSM_® considers cycling when making fertilizer recommendations. The TSM_® programs can reduce the influence that cycles can have on fertilizer effeciency. As a grower continues in the TSM_® program through the years, the result is that fertilizer can be applied in lesser amount yet having  much higher effeciency in the soil. In other words, a soil test can be maintained or built up using less fertilizer.