1. Fertilizer Module 4 Draft FINAL Version August 24, 2009
Florida-Friendly
Best Management Practices
for Protection of Water Resources by the Green Industries
Module 4
Fertilizer
Welcome participants to Module 4.
Draft FINAL Version August 24, 2009

2. Training Objectives At the end of this module you will be able to:
Identify the different types of common fertilizers
Interpret and apply the information on a fertilizer label
Implement practices to avoid runoff and leaching of fertilizers
Calculate the amount of fertilizer to be applied according to the recommended rates
Apply recommended rates
Ask trainee to read objectives out loud.

3. What are fertilizers? Facilitate discussion. Q: What are fertilizers?
A: F.S. -  "Fertilizer" means any substance which:
(a)  Contains one or more recognized plant nutrients and promotes plant growth, or
(b)  Controls soil acidity or alkalinity, or
(c)  Provides other soil enrichment, or
(d)  Provides other corrective measures to the soil.
More generally, fertilizers are natural or synthetic chemical substance or mixture given to plants to promote growth. Plants require different chemical elements to be able to synthesize compounds required for nutrition. In other words, plants can generate their own food through photosynthesis. Some of the elements are available from the environment, but some must be supplied through fertilization. Of the required chemicals, hydrogen, oxygen, and carbon are supplied in inexhaustible form by air and water. Nitrogen is present in enormous quantities in the atmosphere, but it is not accessible to plants in this form; in some cases bacteria can fix nitrogen from the air to a plant.

4. Nutrients From Environment: Carbon Hydrogen Oxygen Macronutrients:
Nitrogen
Phosphorus
Potassium
Calcium
Magnesium
Sulfur
Micronutrients:
Iron
Manganese
Boron
Copper
Molybdenum
Zinc
Nickel
Interpret slide:
Fertilizers can be divided into macronutrients or micronutrients based on their concentrations in plant dry matter.
Macronutrients:
Macronutrients are consumed in larger quantities and normally present as a whole number or tenths of percentages in plant tissues (on a dry matter weight basis). There are six macronutrients: Nitrogen [N], Phosphorus (P) and Potassium (K) , Calcium (Ca), Magnesium (Mg), Sulfur (S). Macronutrients required by turf are primarily N,P,K. Turf requirements for the other nutrient elements are low. Landscape plants in FL are sometimes deficient in Mg.
Micronutrients:
There are many micronutrients, required in concentrations ranging from 5 to 100 parts per million (ppm) by plants. Plant micronutrients include Iron (Fe), Manganese (Mn), Boron (B), Copper (Cu), Molybdenum (Mo), Zinc (Zn) and Nickel (Ni). Micronutrients Fe and Mn can cause nutrient deficiencies in high pH soils or in grass that is irrigated with high pH (reclaimed or from limestone aquifer) water.

5. Soil Test Basis for determining a fertility program
pH as well as macro and micro nutrients
Phosphorus testing is particularly important
Do not soil test for N
Very mobile
Use IFAS recommended rates
Interpret slide:
Looking at soil fertility levels is widely used in commercial agriculture and on golf courses, but is hardly ever done on residential turf. It is important, however, in determining the fertility regime for a home lawn.
Soil testing should provide the basis for determining a fertility program
This includes pH testing as well as extractable levels of macro and micronutrients
Phosphorus testing is particularly important
Do not soil test for N, as it is very mobile – use IFAS recommended rates as guidelines for N fertilization 5

6. Very slightly alkaline
Strongly acidic
Medium acidic
Slightly acidic
Very slightly acidic
Very slightly alkaline
Slightly alkaline
Medium alkaline
Strongly alkaline
Soil pH
Nutrient
Availability
Interpret slide:
Most complete fertilizers contain small percentages of micronutrients. The solubility of these nutrients will depend on the pH of the soil.
Soil pH
0-14 scale
Less than 7 is acid
7 is neutral
More than 7 is alkaline (also called basic)
Affects nutrient availability to the plant
Facilitate discussion:
Q: What is the pH in your area? Acid or alkaline?

7. Quick Release also “water soluble” or “readily available”
Nitrogen Fertilizers
Quick Release
also “water soluble” or “readily available”
Interpret Slide:
Nitrogen is available from many different sources. Two main categories of N products are “quick release” and ‘slow release.” Quick release fertilizers are sometimes also referred to as water soluble or readily available. These fertilizers typically release N shortly after application, with about a 30 day response period. Because virtually all the N in these fertilizers is available immediately, they should be applied at a lower rate (0.5 lb. N per 1,000 sq. ft.) than slow release N sources. These N sources are readily dissolvable in water and are often applied dissolved in water through a sprayer. They may also be applied in a granular form.
There are many sources of quick release N. N fertilizers can either be applied as a single element product or you may buy a blended fertilizer, which may contain different sources of N.
Many fertilizers use multiple sources of nitrogen together. The sources that we will discuss may be present in varying percentages in different fertilizers.

8. Ammonium Sulfate 21% N (NH4)2SO4
Deep green, longer response than many other soluble N
Highly soluble and leachable
Volatilization
Very acidifying – useful in high pH soils
High salt index – must be watered in
Interpret Slide:
Ammonium sulfate is one type of quick release N.
It is 21% N and provides a rapid response in terms of green up when applied at the correct rates. It is very beneficial to use in high pH soils and will provide the best response (turfgrass greening) where pH is high, such as in coastal areas. It produces a deep green color and often has a longer residual response than other quick release (QRN) sources. Like all QRN sources, it is subject to leaching, but when applied to a turf that is growing in a healthy condition, the tendency to leach is greatly reduced and virtually ALL of the N will be taken up by the grass roots. It is also subject to volatilization, where the N changes form and evolves into the atmosphere as a gas. That is one reason why it is very important to water QRN fertilizers in shortly after application, in order to reduce the loss of the fertilizer this way.
Facilitate discussion:
Q: What is the other reason it is important to water fertilizer in?
A: To reduce shoot burn and get the fertilizer to the roots.
Salt index (SI) of a fertilizer is a measure of the salt concentration that fertilizer induces in the soil solution. It allow comparisons of water soluble fertilizers formulations regarding their potential salt effects. As we all know, placement of some formulations in or near the seed may decrease seed germination or result in seedling injury.

9. Urea 46% N Soluble synthetic organic Nonionic, highly leachable
Subject to volatilization
Low acidity - 1.8/kg N
Low salt index
Interpret Slide:
Urea is a common synthetic N source. It is very high percent N (46%), which makes it very difficult to apply at the correct rates. Like all QRN sources, it is subject to leaching, but when applied to a turf that is growing in a healthy condition, the tendency to leach is greatly reduced and virtually ALL of the N will be taken up by the grass roots. It is also subject to volatilization, where the N changes form and evolves into the atmosphere as a gas. It is low acidifying and has a low salt index.
Urea is an organic compound by definition, although it is a synthetically manufactured fertilizer and all QRN unless it is coated to make it partially SRN. It goes through soil reactions that render it less likely to leach in the soil after a short period of time (~24 hrs).

10. Ammonium Nitrate 33 – 34 % N Very soluble
Subject to volatilization and leaching
Low acidity - 1.8/kg N
High salt index
Can be explosive
Short term response
Interpret Slide:
AN is not as commonly used as it once was due to the potential for explosion when combined with combustibles. It is still sometimes an ingredient in blended fertilizer products. It provides a short term response and has characteristics of leaching and volatilization similar to the other QRN sources.

11. also “controlled release” (CR) or
Nitrogen Fertilizers
Slow Release
also “controlled release” (CR) or
water insoluble (WIN)
Interpret Slide:
Some N sources are slow release or controlled release, meaning that the N is not all released right away, but becomes available slowly over time due to reactions that typically occur with microbes or water. Many of the SRN sources have both a QR and SR component, providing an initial response (greening) and longer residual response.

12. Urea Formaldehyde Insoluble organic 38% N; 65-71% WIN
Biological N release
Rate influenced by soil temperature
Less effective in cool seasons
Microbes release N as urea
Interpret Slide:
UF covers a variety of products under different brand names, with liquid forms having slightly different chemical structures from the granular forms. Examples include Nitroform, Powder Blue, Blue Chip, and CoRon. These products are composed of polymer chains that are of varying lengths. The longer the chain, the longer the time for N release. These products will not dissolve in water and contain a high percentage (65-71%) of water insoluble N. The N release is due mainly to soil microbes that make the nitrogen available as urea. The release of UF products is therefore dependent upon soil temperature, which will lead to increased microbe population as temps increase. It is not an effective fertilizer source in cool temperatures. UF may also be found in solution form with a slightly different chemical structure.

13. Methylene Urea 40% N - 36% WIN Biological N release
More rapidly available than UF
Not as adversely influenced by cool temperatures
Interpret Slide:
Another UF fertilizer is methylene urea, which has a much lower percentage of WIN than UF, making it slightly more soluble and readily available. N release is due to microbes and it will typically provide better performance in cool temps than UF. It is typically marketed as Nutralene.

14. Isobutylidene Diurea - IBDU
90% slow release
N released by hydrolysis as urea
Relatively unaffected by
Temperature pH
Particle size important
Excellent cool season response
Less effective during heavy rain periods due to rapid release
Interpret Slide:
IBDU is typically 31% N and is ~90% SRN. N is released through hydrolysis- in presence of water, it splits into urea and isobutyraldehyde. This occurs fastest in low pH and high temps. IBDU is available in different grades, with finer products becoming available more quickly. Not dependent upon microbes for N release, so this fertilizer performs better than many others at low temps.

15. Sulfur Coated Urea 32-38% N Release depends upon:
Thickness of sulfur coating
Biological
Soil environment
Temperature pH
Cool season response-erratic
Drop spreaders may crack pellets
Response up to 4 months
Interpret Slide:
Sulfur-coated urea (SCU) is made by spraying pre-heated urea prills or granules with molten sulfur. A sealant, such as wax or a mixture of oil and polyethylene, is often applied to seal pores and imperfections in the sulfur. Nitrogen content is usually in the range of percent and depends on coating thickness. Increasing the thickness lowers the nitrogen content. Nitrogen is released from SCU by microbial degradation of the sealant and diffusion of soluble nitrogen through pores and cracks in the sulfur coating. The release rate quickens as coating thickness decreases and as temperature increases. Also, breakage of the coating as a result of mechanical damage or aging enhances the release of nitrogen.
SCU is not reported as water insoluble nitrogen on the label because the laboratory analysis process at FDACS destroys the sulfur coating.

16. Polymer Coated Variable N May contain other sources, other nutrients
N release influenced by
Coating thickness
Diffusion rate
Soil temperature
Good for both warm and cool season
Longer residual in warm temps
Interpret Slide:
Polymer coats provide a much more uniform release rate than sulfur coats. Release is by diffusion through a semipermeable membrane. This technology provides good response in either warm or cool temps (faster release in warm temps). This are usually more expensive.

17. Leaching & Runoff Potential
Quick release sources vs. slow release sources
Quick release sources, properly applied, do not leach significantly more
The potential for leaching due to misapplication or overwatering is greater with soluble sources
The potential for leaching due to heavy rain soon after applying is greater with soluble sources
The potential for runoff due to heavy rain several weeks after application may be greater with slow release sources
Interpret Slide:
Proper application of fertilizer is what is most important. If you are using a soluble quick-release source, there is greater potential for leaching to occur, but if applied properly and in the right amounts, soluble sources may be just as appropriate as slow release sources.

18. Why use slow release fertilizers?
Facilitate discussion:
Q: Why use slow release fertilizers? A:
Greater Efficiency of applied N
More uniform long-term growth response
Interpret slide:
There are advantages to using SRN sources as are shown here. Applicators should remember that these fertilizers will not usually provide an immediate response in green up or growth and that does not mean that enough fertilizer wasn’t applied. It is also important to note that some of these fertilizers have a low weight and may float easily in water, which can increase runoff.

19. Phosphate Fertilizers
Fertilization of Established Grasses:
Should be applied based on soil and/or tissue test
Often ample in plant available form in FL
Turf needs are low
DACS Fertilizer Rule limits use:
0.25 lb 1,000 ft-2 per application
0.5 lb 1,000 ft-2 yearly
Needs increase under traffic or other stresses
Interpret Slide.
Some phosphorus is used in plant structures, but much is used in the energy cycle where it is constantly reused, so only small amounts are needed for normal growth. Florida soils often have enough naturally for established turf. In many waters it is a serious pollutant.

20. Potassium Potassium is like a multi-vitamin for turf
Provides some resistance to many stresses
Is not a curative, but should be part of a fertilization plan
N:K ratio 2:1 or 1:1 under stress
Interpret slide:
Potassium does not enhance turfgrass growth or turn the grass green. It functions within the cells and does many important things on that level. You will not see a response to an application of potassium, but it is important for the plant to be supplied with it.

21. Magnesium (Mg)
A Magnesium deficiency may be found in many parts of the State
2 ½ lbs. Mg/1000ft²/yr may be applied
Interpret slide:
There are certain locations in the state where landscape plants show symptoms of Mg deficiency. To take care of this problem up to 2.5 pounds of Mg may be applied per 1000 ft 2 per year. This deficiency is usually in landscape plants and palms, not turf.

22. What about micro nutrients?
Interpret slide:
Micronutrients can be applied as needed to achieve fertilization objectives (e.g., high impact, high maintenance landscapes). There are times when additional applications of iron (Fe), manganese (Mn), zinc (Zn) or copper (Cu) are required either because of specific plant requirements or deficiencies, which need to be corrected.

23. Fertilizer Label BRAND NAME GRADE X-X-X Guaranteed Analysis
Total Nitrogen (N)
_____%
Nitrate Nitrogen
Ammoniacal Nitrogen
Water Soluble Nitrogen
Urea Nitrogen
Water Insoluble Nitrogen
Available Phosphate (P205)
Soluble Potash (K20)
Chlorine, (Cl) Not More Than .
Total Magnesium as(Mg )
Water Soluble Magnesium as (Mg)
Chelated Magnesium (Mg)
Total Manganese as (Mn)
Water Soluble Manganese as (Mn)
Chelated Manganese as (Mn)
Total Copper as (Cu )
Water Soluble Copper as (Cu)
Chelated Copper as (Cu)
Total Iron as (Fe )
Water Soluble Iron as (Fe)
Chelated Iron as (Fe)
Total Zinc as (Zn)
Water Soluble Zinc as (Zn)
Chelated Zinc as (Zn)
Combined Sulfur as (S)
Free Sulfur as (S)
Derived from: (Actual materials and in forms used in the fertilizer mixture, e.g., Diammonium Phosphate, Urea, Potassium Chloride, Magnesium Sulfate, Manganese Nitrate, etc.)
Manufactured by:
Name (FXXXX)
City, State & Zip
Net Weight - _______ lb
Fertilizer Label
Interpret slide.

24. Do you need a license to apply fertilizers?
Facilitate discussion.
Q: Do you need a license to apply fertilizers? A:
Soon! Beginning January 1, 2014, a Limited Commercial Fertilizer Applicator Certificate (LCFAC) by 2014 from FDACS will be required by state law to apply on any but your own or your employer’s property.  A certificate of training in the Green Industry BMPs, or an approved equivalent, is required to apply for the FDACS license, and by many local ordinances.
New FS providing for limited certification for urban landscape commercial fertilizer application provided by the Department of Agriculture and Consumer Services; requiring such certification in order to commercially apply fertilizer, beginning on January 1, 2014; providing requirements and fees; providing for expiration and renewal; authorizing the department to provide information concerning persons who are certified; providing for exceptions to the requirements of certification.

25. Limited Commercial Fertilizer Applicator Certificate (LCFAC)
Issued by FDACS - Chapter 482
Required by January 1, 2014
GI-BMP training certificate pre-requisite [approved equivalent]
$25 fee, renewal every 4 years
4 hours of CEUs required for renewal
Not required if application is only to property owed by you, your firm, or your employer
LCFAC holders are exempt from further local testing
Interpret slide.

26. Fertilizer Calculations
Transition slide.

27. Single N Applications Depends on percentage slow-release N:
0.5 lb. N 1000 ft2 if water soluble
Up to 1 lb. N 1000 ft2 if slow-release
Follow UF recommended annual N rates
Interpret slide:
Frequent, small fertilizer applications are more beneficial for turf than large, infrequent doses. BMPs call for specific rates of fertilizers per application, depending on whether the N is QRN or SRN or a combination of both.

28. N Calculations How much N per 1,000 ft2?
, 50% slow-release N
How much N per 1,000 ft2?
Facilitate discussion:
Q: How much N do we want to apply per 1,000 square feet with this product?
A: 1 lb of Total N

29. How much 15-0-15 will supply the correct N amount to 1,000 ft2?
N Calculations
How much will supply the correct N amount to 1,000 ft2?
Facilitate discussion:
Q: How much 15% N fertilizer will supply the correct amount to this size yard?
Allow attendees to answer. The correct answer is in the next slide.

30. 6.6 lbs. to cover 1,000 ft2 at 1 lb N /1,000 ft2
N Calculations
100/15 = 6.6
6.6 lbs. to cover 1,000 ft2 at 1 lb N /1,000 ft2
Interpret slide.

31. Fertilizer Calculations- Milorganite
How much fertilizer?
Facilitate exercise:
Ask the audience to conduct this calculation. Once they are done ask if someone would like to come to the front and do the exercise for the class.

32. 100/6 = 16.6 Fertilizer Calculations- Milorganite
Formula> 1 lb /1,000 ft2
100/6 = 16.6
16.6 lbs. to cover 1,000 ft2 at 1 lb N /1,000 ft2
Remember that this product has 2% phosphorus, only 12.5 lb. may be applied if there is not a P deficiency
Interpret slide.
The Florida Fertilizer rule limits P2O5 application to 0.25 lb./1000 sqft. per application, or 0.50 lb./1000sqft./year.

33. Fertilizer Calculations- Urea
How much (quick release) fertilizer?
Interpret slide.

34. Fertilizer Calculations- Urea
Formula> 0.5 lb /1,000 ft2
100/46 = 2.2
To apply 0.5 lb. N per 1,000 ft2:
2.2 /2 = 1.1
1.1 lbs. to cover 1,000 ft2 at 1 lb N /1,000 ft2
Interpret slide.

35. 6% N (Low) Larger amounts of fertilizer
15% N (Medium) Medium amounts of fertilizer
46% N (High) Very Low amounts of fertilizer
Interpret slide.

36. Fertilizer Calibration, Application, Storage
Transition slide.

37. Calibration Calibrate spreaders & sprayers frequently
Ensure they are clean and maintained properly
Double check the material used and application rate desired
Facilitate discussion:
Q: Why is calibration important?
A: Calibrating will improve accuracy of technicians when applying either fertilizer or pesticide and can reduce nonpoint source pollution from applying too much, or inadequate plant response if too little.
Continue interpreting slide.

38. Spreader Calibration Determine amount needed for the test area
Capture material (bucket or measured tarp)
Walk the spreader over test area
Weigh applied material
Compare to the required amount
Adjust spreader
Interpret slide.

39. Sprayer Calibration
Determine how much fertilizer is needed for the test area
Determine how long it takes to spray that area
Determine the amount sprayed in that time
Compare and adjust as needed
Interpret slide.

40. Application Deliver the fertilizer to the target
Check the delivery rate
Check for appearance
Avoid non-target surfaces
Operate the equipment safely
Interpret slide.
Facilitate discussion:
Q: What is the target for most fertilizers?
A: Root zone (unless foliar applications). Make sure to get the fertilizer to the target and not offsite. With an established turf that has a dense root and shoot system, it is pretty easy to hit the target. With landscape plants, there may be more tendency to get fertilizer off site from the direct root ball.

41. 40’ x 25’ = 1,000 square feet of front lawn
Application
Measure the lawn area
40’
25’
Interpret slide.
40’ x 25’ = 1,000 square feet of front lawn

42. Application Take half of the total amount of fertilizer:
15% = 6.6 lbs fertilizer per 1,000 square feet
Half of this = 3.3 lbs fertilizer in spreader
Interpret slide.
Then take the remaining fertilizer and go in other directions

43. Application
Then take the remaining fertilizer and go in opposite directions
Interpret slide.
This will help you apply the correct amount of fertilizer!

44. Buffer? Interpret slide:
These points are the foundation of the Green Industries BMPs. It is everyone’s responsibility to follow these and avoid potential situations where we might get leaching of fertilizers or chemicals into ground or surface waters.

45. Application Use a deflector shield near water Leave at least 3’ ring
Without a shield leave 10’ ring
Ordinances may vary
Use the shield near impervious areas and storm water systems
Interpret Slide:
Stay 3’ from water bodies if using a deflector shield- does everyone know what a deflector shield is? It keeps the fertilizer granules in a 180 arc, rather than a 360 arc and should always be used around water bodies. It is also very helpful for edges of paved areas. If not using a deflector shield, maintain a 10’ zone. These rules do not apply to those counties or cities where there may be fertilizer ordinances in place that have greater distance requirements. Be sure to know, understand, and follow any local laws, they do pre-empt the BMPs.

46. Only enough water to move granules off of leaves
Application
¼ Inch
Only enough water to move granules off of leaves
Interpret Slide:
To get fertilizer to the target (roots) and to reduce potential leaf burn or volatilization, fertilizer should be watered in with ~1/4” water. That will wash the granules off the leaf blades and work them into the top couple inches of soil. More water than that may run the risk of washing (leaching) the fertilizer past the root zone.

47. Fertilizer on impervious (paved) surfaces can pollute water bodies
Sweep-up spills!
Fertilizer on impervious (paved) surfaces can pollute water bodies
Interpret Slide:
NEVER leave fertilizer granules on an impervious (paved, concrete) surface where it could be washed down storm drain. Sweep the granules up and either put back in bag or, if a small amount, put on grass.

48. Fertilizer Storage Store fertilizer in areas protected from rainfall
Load fertilizer away from wells or waterbodies
Store fertilizer away from flammable substances
Clean up spills immediately
Interpret Slide:
Don’t leave fertilizer outside where it can get wet or bags damaged by humidity- this will result in spilled fertilizer. Do not load spreaders near a well or water body, best to do over some type of containment pad. Remember that many fertilizer products are flammable, so keep them away from products that might cause them to combust. Be sure to clean up spills before they have a chance to move offsite.

49. Irrigation After Fertilization
Even at proper rates, too much water can result in leaching or runoff
Irrigate fertilizer in with ¼” of water
Do not fertilize when heavy rainfall is expected
(NWS tropical watch or warning or flood watch for the area)
Interpret slide:
Amount of water applied through either irrigation or rainfall following fertilization is a critical key in reducing potential leaching. You want to move the fertilizer particle off the leaf blade to just below the soil so the roots can take the fertilizer up. Too much water will move the particles past the root zone, where they can then leach into ground water.
Irrigation is addressed in Module 3.

50. Review
Proper application is more important than the type of fertilizer
Soluble N sources differ in chemical properties and handling requirements
Slow-release N sources are not 100% slow-release and they differ in their release properties
Interpret Slide:
All of the principles covered in this module are important for environmentally safe fertilizer application. Proper handling, rates, and timings of applications are very important in reducing nonpoint source pollution from fertilizers. It is important to be knowledgeable, alert, and to keep clients informed about fertilizer handling and expectations.

51. Review (continued)
Knowledge of fertilizer management is one of the most important tools in limiting the environmental impact
Irrigation Management is the other critical tool
Educating the customer is critical
New Limited Commercial Fertilizer Applicator Certificate (LCFAC) by 2014
Interpret Slide.

52. Thank you! This slide set was adapted from the presentation
SOLUBLE vs. CONTROLLED RELEASE NITROGEN FERTILIZERS by J.B. Sartain
University of Florida by
Mike Thomas, FDEP
Laurie Trenholm, UF-IFAS
Alberto Chavez, FDEP
Last update August 24, 2009