1. FRUIT GROWERS LABORATORY, INC.
Chad Lessard
Certified Crop Advisor
Director of Agricultural Services

2. Talking points for interpreting your soil and tissue analysis reports
Primary Nutrients and Macronutrients
N, P, K, Ca, Mg, S
Secondary Nutrients and Micronutrients
Fe, Zn, Mn, Cu, B, Cl, Mo
Other Chemical Properties
pH, cation exchange capacity, soil salinity, limestone
Quality Control
Database Management Systems
First

3. Understanding Your Soil Analysis Report
Soil Rpt

4. Start w/ N

5. Common Nitrogen Questions
Q. Why is nitrate-nitrogen only analyzed in the soil and not ammonium and/or total nitrogen?
A. Under conditions favoring plant growth, most forms of
soil nitrogen are rapidly converted to nitrate.
2 NH O2  2 NO H20 + 4H+
Q. Why is the nitrate bar blue?
A. The blue bar indicates there really is no “optimum range.” Soil nitrate requirements are primarily dependant on the growth stage of your crop and soil temperature.
On to N Avail

6. Nitrogen Availability
Nitrogen uptake efficiency during critical stages
25% when applied to the soil in a single annual application
50 – 60% when applied to the soil in 3 to 4 increments
- Fertigation may be the easiest way to accomplish these incremental applications
Closer look at soil N avail

7. Nitrogen Availability
Soil application
Average nitrogen losses = 20 – 50 percent
Leaching losses - apply nitrogen in short irrigation runs or at the end of a normal run
Volatilization - urea and ammonium sources should not be applied at high pH, high temperature, or on the soil surface
Immobilization: significant for organic growers
High soil carbon content = Immobilization
C:N Greater than 30:1 = N immobilization
C:N 20:1 to 30:1 = about equal mineralization to immobilization
C:N Less than 20:1 C:N = more rapid N mineralization
OM mtrl to use

8. Properties of Different Organic Materials
C:N ratio
Undisturbed top soil
10:1
Alfalfa
13:1
Manure
20:1
Corn stalks
60:1
Green waste
80:1
Coal and shale oil
124:1
Oak
200:1
Spruce
1000:1
*When using the high carbon content materials be sure to
apply 15 – 25 pounds of extra nitrogen fertilizer to facilitate mineralization
Next is P

9. Common Phosphorus Questions
Q. Why is phosphorus reported as P2O5?
A. Phosphorus fertilizer is sold as P2O5 equivalent
To convert from P2O5 to P multiply by
Q. Why are there two different methods for soil P analysis?
A. Depending on the pH, phosphorus exists as two different ions so there are two different extraction solutions to mimic actual P available to your crop.
Dif P forms available

10. Phosphorus Availability
Different precipitates of P
Important to monitor pH for P
Some K ?s

11. Common Potassium Questions
Q. Why are there two different potassium results?
A. Potassium is measured in two ways.
1. Exchangeable (Exch)
The exchangeable portion is the potassium available as a reserve in your soil. This moves into solution as the soluble K is taken up.
2. Soluble (Sol)
The soluble portion is the potassium most readily available.
So just because

12. Potassium Availability
Just because your soil has a high exchangeable potassium content, doesn’t mean its all available
4 general forms of K in the soil
Mineral or structural = 5, ,000 ppm
Fixed or difficultly available = ppm
Exchangeable = ppm
Soil Solution = ppm
K avail issues

13. Potassium Availability
Potassium in the soil is mostly available by mass flow…so…
Leaching is possible
Soluble potassium may leach in sandy soils with high rainfall
Foliar applied K is an option for most crops
If foliar application use KNO3
Some crops can’t absorb foliar applications thus, water soluble forms of K should be applied to the soil
Potassium Thiosulfate appears to be the most available source
Lets few more K avail issues

14. Potassium Availability
Potassium and crop yields
Most directly related nutrient to high crop yield
High N and P increases yields as well but also increases the total demand for K to support that yield
K released from the exchangeable sites in the soil is often too slow to supply ample amounts in a high yield system
On to the secondary nutrnts

15. Calcium, Magnesium, Sodium and Sulfur
Q. Why are these nutrients considered secondary?
A. This just means they are not normally needed in as large of
of quantities as the primary nutrients.
-Secondary nutrient deficiencies can depress
plant growth just as much as
primary nutrient deficiencies.
-Sometimes, plants can even require
more S and Ca than P.
Next section Chem Props

16. Cation Exchange Capacity, pH, % Base Saturation, and the Lyotropic Series
The “Easy” Definitions:
Cation Exchange Capacity – The total amount of cations a soil can hold on its negatively charged particles (the clay and humus)
Percent Base Saturation – The percent of a certain cation that is held on the CEC in comparisons to the other cations
pH – A measurement estimating the “active” hydrogen ions
Lyotropic Series – The order in which cations will bond with the negative charges in your soil Al3+ > Ca2+ > Mg2+ > K+ = NH4+ > Na+
Percent Base Sat

17. Percent Base Saturation
No relationship to crop yields
Sufficiency levels of each nutrient should be used to make fertilization recommendations
However percent base saturation is still important
Predicting soil structure
In a typical soil, the percent base saturation
is directly related to the lyotropic series
Next prop to look at is pH

18. ___________________________
Adjusting the soil pH changes more than just the pH
___________________________
Another ? on Micros

19. Metal Micronutrient Availability
If my soil pH is between 5.5 and 7 and I still have micronutrient deficiencies?
Chelated micronutrients are the way to go for soil applications
Chelated micronutrients are 6 – 10 times more effective than non-chelated micronutrients
Chelates prevent micronutrients from precipitating with other ions in the soil and allow them to move with water to the root.
How they work

20. Metal Micronutrient Availability
How chelates work
Apply to the soil
and irrigate
*Chelate is derived from the Greek word meaning crab claw
*May suppress the growth of plant pathogens by iron deprivation
On to plant tissue rpts

21. Understanding Your Plant Tissue Analysis Report
Tissue reports show

22. How to use your tissue analysis report
A tissue analysis report shows
The sufficiency of nutrients in your trees
Indicates the plants ability to extract nutrients from the soil
Tissue exmpl

23. Your Fertilization Management Report Card
Tissue Analysis
Your Fertilization Management Report Card
*Your tissue analysis report should be used along with your soil analysis data to
optimize your nutrient management plan
How to use this

24. How to use your tissue analysis report
If nutrient levels are optimal, then your nutrient management program is well balanced
If not, your tissue report will indicate which changes are necessary to your nutrient management program
Compensation must be made for crop nutrient removal
A freq asked question

25. How to use your tissue analysis report with your soils report
A frequently asked question
Q. Why does my soil report show ample nutrient levels and my leaf tissue report shows deficiencies?
A. Because crops are not always capable of taking up the necessary amounts of nutrients to support their rate of growth and yield.
Transition to QA / QC

26. Quality Assurance / Quality Control
Quality Assurance….is the overall process used to ensure accurate and precise results
Quality Control…. is the actual steps taken such as blanks, standards, spikes, and duplicates used in the above process
A visual example

27. Quality Assurance / Quality Control
We need to use QA / QC because you need to know your data is precise and accurate
Imprecise and inaccurate
Accurate but imprecise
Inaccurate but precise
Precise and accurate
(Valid Data)
Reporting options

28. Reporting of Testing Results
Color graphic reports by mail
Web reporting on FGL’s password protected website
Alternatively
Trans to database mgmt

29. Database Management Systems
These systems catalog and organize information making it easily accessible to assist with decisions regarding fertilization and amendment programs
What else?

30. Database Management Systems
Provides tools for making comparisons between previous years’ performances, different blocks / properties and different management practices
Parameters can be tailored to specific crops, crop growth stages, or even specific growers
Supported dbms

31. Fruit Growers Laboratory, Inc. Supports
SureHarvest
AgCode
Most Company Specific Reporting Formats
End

32. Questions? Fruit Growers Laboratory, Inc. For more info: Chad Lessard
Fruit Growers Laboratory, Inc.