Turfgrass Nutrition

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Turfgrass Nutrition
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Soil Test

• Six inches deep
• Mix up a pint
• When?
• establishment to till into soil
• yearly or other year

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(No Transcript)
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Nitrogen

• Deficiency symptoms
• Chlorosis (yellowing)
• Turf will look hungry
• Slow growth
• Amount of clippings collected

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Nitrogen

• Excessive N
• Reduced root growth
• Increased shoot to root ratio
• More shoots, fewer roots

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Nitrogen

• Excessive N
• Increase thatch accumulation

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Nitrogen

• Excessive N
• Succulent growth
• Prone to disease and insect
• Cells walls are thinner

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Phosphorus

• Importance is in the root growth

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Phosphorus

• Starter fertilizers are high in P
• Limited root systems
• Higher demand for P during early stages

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Phosphorus

• Immobile nutrient
• Will not move into the soil solution
• Extremely fibrous root system will get it
• Fertilizers generally low in P

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Phosphorus

• P deficiency
• Purple discoloration
• Rarely seen in turf
• Dont confuse with cold

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POTASSIUM

• Stress nutrient
• Improves heat and cold tolerance

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POTASSIUM

• Deficiency symptoms not distinct
• Best used in 11 ratios with N

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IRON

• Micronutrient most likely to be deficient in turf
• Effects only the foliage applied to, not new
  growth
• Keeps good color without growth

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IRON

• Iron deficiency
• Chlorosis on new growth
• High pH soil changes iron to an unusable form

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IRON

• Forms of Iron
• Iron Sulfate
• Cheap
• Short lasting
• Iron Chelate
• Expensive
• Keeps iron in a more useable form
• Longer impact STABLE!

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CEC, Cation Exchange Capacity

• Nutrient holding potential of soil
• Cations are positively charged elements
• Anions negatively charged

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CEC, Cation Exchange Capacity

• Nutrient holding potential
• Soil particles, particularly clay and OM, have
  negative charge
• Soil attracts and holds cations
• K, Ca, Mg, NH4

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CEC, Cation Exchange Capacity

• Anions leach through soil
• NO3 (nitrate)
• Almost all N is available as NO3
• Sand has low CEC, thus low fertility

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Fertilizer
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Fertilizer Analysis

• 3 numbers are N - P - K (complete fertilizers)
• Nitrogen, Phosphorus, and Potassium

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Quick Release Nitrogen

• Water-soluble
• Immediately available to plant
• 1 to 2 week supply
• Frequent, lower rates
• Spoon feeding

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Quick Nitrogen Release

• High burn potential
• Do not apply over 1 pound N / 1000 ft2
• Water in after application
• Susceptible to leaching

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Quick Nitrogen Release

• Inexpensive
• Urea very common form

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Too Much Urea
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Slow Release Nitrogen

• Extended period of time N is released
• Generally 6 to 10 weeks

Slow release N response
Quick release N response
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Slow Nitrogen Release

• Not all N in package slow release
• Less burn potential
• Less susceptible to leaching

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Coated Slow-release

• Size variation
• Larger granules
• Damage affects N release

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Sulfur-coated urea (SCU)

• Urea covered with sulfur and wax
• MO breaks down the S coating

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Sulfur-coated urea (SCU)

• Imperfect release due to imperfections of coating
  and damage
• Least expensive

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Polymer-coated

• Perforated synthetic coating
• Osmocote most popular (not for turf)
• 5 to 16 months release
• Coating thickness

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Polymer-coated

• Might be combined with sulfur-coated

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Non-coated Slow-release

• Uniform size
• Smaller granules
• Less damage

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Ureaformaldehyde

• Nitrogen tied up in complex formaldehyde
  molecules
• Dependent on MO to break down
• Release faster in warmer, wet weather

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Ureaformaldehyde

• Ureaform
• Nitroform, UF, Blue Chip products
• Long complex N-chains
• Slowest release

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Ureaformaldehyde

• Methylene Ureas
• Nutralene products
• Intermediate N-chains

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IBDU

• Isobutylidene Diurea
• Water releases nitrogen
• Release not as affected by temperature or MO
• Particle size affects release

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Organic

• Manure, bone meal, sludge
• MO breaks down
• Come in very low N
• May improve soil over time
• Very low burn potential

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Organic

• Milorganite, product of Milwaukee Sewage
  Commission
• Activated sewage sludge contains 6 N
• Lower disease and insect

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Organic

• Corn Gluten
• 10 N
• Also, pre-emergent herbicide

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Applications

• Use 1/2 rate in heavy shade
• Turn off at turns
• Water immediately
• Avoid spills that burn grass

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Application

• Commercial spreader
• 30 to 50

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Application

• Rotary spreader
• 6 to 10

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Application

• Drop spreader
• Striping more likely
• Hand spreader

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Applications

• First Application (Nitrogen) end of April

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Applications

• Last Application Mid-August with N
• Sept or Oct apply with P and K

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Applications

• Timing
• Make applications between 4 to 6 weeks apart
  depending on fertilizer

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Applications

• Each application 1 pound N / M
• Bermuda, St. Augustine and zoysia
• As many as 4 applications per year
• May, June, July and August

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Applications

• Each application 1/2 pound N / M
• Centipede
• 2 applications per year
• May and August
• Centipede use low P

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Fertilizer Label

• Spreader setting on bag

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NITROGEN FERTILIZATION

• How many pounds of fertilizer has 1 pound of
  Nitrogen?
• CALCULATOR
• 25-3-18 ratio has 25 N
• 100 pounds of fertilizer
• Has 25 pounds N

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NITROGEN FERTILIZATION

• How many pounds of fertilizer has 1 pound of
  Nitrogen?
• 100 DIVIDED BY Nitrogen
• 100 / 25 4
• 4 pounds of fertilizer (25-3-18)
• has 1 pound N