connect forage fertility...•pastures require less fertilization than field crops. •grazing...
TRANSCRIPT
CONNECT Training Forage Soil Fertility
Gene Pirelli, Polk County
Mylen Bohle, Crook County
OSU Extension Service
Pasture and Grazing Management
• What Do You Want From a Pasture?
– Feed Quality
– Feed Quantity
– Palatability
– Quality of Turf, Durability and Longevity
– Grazing Tolerance
– Seasonal Production (Spring, Summer, Fall, Winter)
– Animal Health
– Animal Performance
Key Points About Pasture Fertility
• Soils are a basic resource that must be considered in
management decisions. Degradation of the soil resource
can take a lifetime to recover.
• Nutrients in a soil-plant-animal system are dynamic and
cyclic.
• Intensive management and high stock density are required
to minimize the tendency to be concentrated near water,
shade, and other attractions.
• Soil testing (and in some cases plant tissue testing) is
essential to prescribing nutrient additions to pasture
Grazing: What is Happening in the Pasture
• Affects plant growth by defoliation
• Animal Traffic patterns & compaction
• Herbage fouling
• Partitioning of nutrients to body, urine, and feces
• Dispersion / Redistribution of nutrients in urine and feces
Soil Fertility Management
• Sufficiency – Economic Response
• Maintain – What you remove, you put back
• Build the soil – Add back more than removed
Soil Sample
• How to Take A Soil Sample
• Pasture: Sample 0-6 inches for Everything
• Hay Field: Sample 0-12 inches for Everything
Sample 0-6 inches for pH in case SMP Buffer Test is Needed.
• Test is Good for 2-3 Years
• “Monitor”
General Soil Test Critical Numbers
• Nutrient Grass Alfalfa pH 5.3-8.5 5.8-8.5 (7.0) P 10 15 K 150 (?) 150 (?) S >9 >9 Ca 1,000 1,000 B N.A. 0.5 Zn 1.0 (?) 1.0 (?) Mg 60 60 Cu 0.6 0.6 Mn 1.5 1.5 Cl ? ? Mo ? ? Sol Salts <1.0% <1.0% Se N.A. N.A. Na <10% <10%
General Nitrogen Recommendations for Irrigated and High Rainfall Grass and Grass-
Legume Pastures Plant Composition
Yield Potential of the Pasture
1 - 2 (tons/acre)
2 – 4 (tons/acre)
4-6 (tons/acre)
6-8 (tons/acre)
Nitrogen Fertilizer (lb./ acre)
100% Grass
50 75 100-150 150-200
75% Grass / 25% Legumes
25 50 75-100 100-150
50% Grass / 50% Legumes
0 25 50 75
25% Grass / 75% Legumes
0 0 25 50
General Phosphorus Recommendations for Grass and Grass-Legume Pastures in the
Interior Columbia Basin P Recommendation
(lb./P2O5 / acre)
Soil Test P (ppm) Irrigated Rain-fed
0-3 100-125 60-100
4-7 75-100 40-60
8-10 50-75 20-40
11-15 0-50 10-20
>15 0 0
Pasture and Grazing Management in the NW, 2010
General Potassium Recommendations for Grass and Grass-Legume Pastures
Soil Test K (ppm)
K2O Recommendation (lb/K2O / acre)
0 - 40 180 – 220
40 – 70 140 – 180
70 – 100 80 – 120
100 – 150 40 – 60
> 150 0
Pasture and Grazing Management in the NW, 2010
Sulfur Recommendations
• Sample 0-12 inch depth
• If > 10 ppm: No need to apply
• If < 10 ppm: Apply 30 lb./acre Sulfur
• High Rainfall / Irrigated: Apply Annually
General Micronutrient Soil Test Values (ppm) and Interpretation
Nutrient Low Marginal Adequate
Zinc < 0.8 0.8 – 1.0 > 1.0
Iron < 3.0 3.0 – 5.0 > 5.0
Copper < 0.2 -- > 0.2
Manganese < 1.0 -- > 1.0
Boron < 0.25 0.25 – 0.50 > 0.5
Pasture and Grazing Management in the NW, 2010
Nutrient Distribution Cycling in a Grazed Pasture
• Pastures require less fertilization than field crops.
• Grazing livestock return as much as 85 to 95 % of the Nitrogen, Phosphorus, Potassium, and other nutrients consumed to the pasture through urine and dung.
• Nutrients are not distributed uniformly, however. They are concentrated next to the water source, shade, bedding areas, and trails.
Pasture and Grazing Management in the NW, 2010
Nutrient Distribution Cycling in a Grazed Pasture (cont.)
• After 4-5 grazing seasons, and P and K concentrations within 30 feet of water sources can be 5 times greater than other areas of the pasture.
• When grazing patterns remain unchanged for more than 20 years, increased P and K concentrations can be found up to 100 feet from the water source
Pasture and Grazing Management in the NW, 2010
Concern about Manure in Pasture
• To Reduce Parasites, you can pick up the manure from the pasture
• Animals do not eat where they defecate
• Compost properly before applying back out on pasture
• Harrow your pastures to break up manure piles
• If Grazing “Properly”, manure breaks down more rapidly
Plant Tissue Testing
• If you want to tissue test your pasture, clip vegetative plants between 3-4 inches and 6-9 inches or so.
• Collect about 25 plants or samples.
• Deliver the samples to the lab the same day or air dry plants before shipping
Plant Tissue Testing (cont.)
• Example: pasture clipped just before heading would contain about:
• 2.0 % N
• 0.25% P
• 1.5% K
• 0.2% S
Pasture samples test results will generally be higher than these numbers
Fertilizer Application Based on Soil Test
• Nitrogen – 3 applications annually of 50-60 lb/acre??
• Phosphorus ? • Potassium ? • Sulfur
– 20-30 lb./acre annually
• N - P - K - S • 16 - 16 - 16 - 16 • (Nitrogen, Phosphorus, Potassium, Sulfur)
1992 Grass Yield (ton/acre) Response to Nitrogen Fertilizer in Central Oregon
N Rate (lb/acre)
Bluegrass/Clover
Old Orchard
Timothy Old Mixed Grass/Leg
New Orchard
Orchard/ Legume
1st Harvest 1992
0 0.45* 1.30 0.68 0.72 1.51 1.11
50 0.89* 2.15 2.18 1.88 2.66 1.95
2nd Harvest 1992
0 0.30 -- 0.13 -- 0.99 1.58
50 1.27 -- 1.03 -- 1.96 1.89
3rd Harvest 1992
0 0.32 0.63 -- 0.27 0.75 Drought
50 1.24 1.42 -- 0.63 1.72 Drought
* Cattle grazed before harvest, -- plots compromised by additional fertilizer
Mylen Bohle, OSU Extension Service
1993 Grass Yield (ton/acre) Response to Nitrogen Fertilizer in Central Oregon
N Rate (lb/acre)
Bluegrass/Clover
Old Orchard
Timothy Old Mixed Grass/Leg
New Orchard
Orchard/ Legume
1st Harvest 1993
0 0.83 1.31 -- -- 1.44 2.24
50 2.15 2.02 -- -- 2.72 2.74
2nd Harvest 1993
0 0.97 0.66 0.22 0.98 0.85 1.73
50 1.21 1.93 1.87 1.29 1.65 2.40
3rd Harvest 1993
0 0.35 0.03 0.10 -- 0.17 0.10
50 0.61 0.23 0.37 -- 0.94 0.36
-- plots compromised by additional fertilizer
Mylen Bohle, OSU Extension Service
T-Sum N Timing
• Add GDD’s from January 1st until reach 360 gdd’s F
• Add high and low temp / 2 = average – 32 degrees F base temp
• Examples
– 50 – 32 = 18 (add) 18
– 30 – 32 = -2 (discard) 18
– 36 – 32 = 4 (add) 22
March 3, 2010 T-Sum N Timing Update
• Christmas Valley: 206 gdds
• Bend: 360 gdds
• Powell Butte: 365 gdds
• Madras: 396 gdds
• Time to fertilize pastures, or should have fertilized pastures, if you want to shift pasture forage production up earlier in the spring
• (For Hay T-Sum N Timing is 720 gdds)
T-Sum N Timing Effect on Grass Pasture Powell Butte 1999
0
500
1000
1500
2000
2500
Check 353 554 754
T-Sum Timing (gdd's)
Yie
ld (
lb/a
c)
1st Graze 2nd Graze
T-Sum N Timing Effect on Grass Pasture Powell Butte 2000
0
500
1000
1500
2000
2500
Check 324 533 726
T-Sum Timing (gdd's)
Yie
ld (
lb/a
c)
1st Graze 2nd Graze
T-Sum N Timing Effect on Grass Pasture Madras 1999
0
500
1000
1500
2000
2500
Check 331 595 775
T-Sum Timing (ggd's)
Yie
ld (
lb/a
c)
1st Graze 2nd Graze
T-Sum N Timing Effect on Grass Pasture Madras 2000
0
500
1000
1500
2000
2500
Check 352 500 740
T-Sum Timing (gdd's)
Yie
ld (
lb/a
c)
1st Graze 2nd Graze
OSU’S FG 63
• Includes recommendations for major nutrients in Western Oregon
• Helps to interpret soil test results
• Provides guidelines for pounds of nutrients to apply
Apply to Match Feed Needs
and to Supplement the
System
Nitrogen is a Component of Crude Protein
Forage labs measure crude protein by analyzing nitrogen and multiplying by 6.25
Ruminants use nitrogen as a protein source
Grazing Animals Can Remove a Significant Amount of Nitrogen
Nutrient Requirements for Feeder Lambs
WEIGHT
Daily
Gain
Crude
Protein
(Lbs)
Crude
Protein
(%)
TDN
(%)
65 Lbs .75 Lbs .41 14.5 63
110 Lbs 1.0 Lbs .35 10.0 77
Nutrient Requirements Are High for Growing and
Lactating Animals
Ewe weight
130 lb (1)
155 lb (1)
175 lb (1)
200 lb (1)
TDN
Protein
TDN
Protein
TDN
Protein
TDN
Protein
Stage of Production
lb
Maintenance
1.30
0.23
1.50
0.25
1.60
0.27
1.70
0.29
Early pregnancy
1.60
0.27
1.70
0.29
1.80
0.31
1.90
0.33
Late pregnancy (2)
2.60
0.45
2.80
0.47
2.90
0.49
3.00
0.51
Early lactation, single
3.30
0.70
3.60
0.73
3.70
0.76
3.80
0.78
Early lactation, twins
3.70
0.89
4.00
0.92
4.30
0.96
4.60
0.99
Early lactation, triplets (3)
3.90
0.99
4.20
1.02
4.60
1.06
5.00
1.10
Grazing Animals Return
Nitrogen and Other Nutrients
Back to the Soil
Fertilizer, in many cases, supplies only part of the total N consumed as plant protein
T-Sum 200
A method of calculating the appropriate time for the first N
application
Forage
Growth
in
Western
Oregon
pastures
Forage
Growth
in
Western
Oregon
pastures
Feed Increase Needed Here
Benton County Site
Harvested
4/26 Check Mid-
Season
T-Sum plus
mid-season
Pounds of
Dry Matter 2553 2156 5267
Percent
Nitrogen 2.07 1.96 2.34
Nitrogen
Uptake (Lbs/A) 53 42 123
N Application
Date 4/5 2/4 & 4/5
Phosphorus • Apply in Fall
• Stable, Does Not Move once Incorporated into soil.
• Soil Test to Determine if Soil Levels are Rising
General Phosphorus Recommendations for Grass and Grass-Legume Pastures on the West-
Side of the Cascades Soil Test P
(ppm) P Recommendation
(lb/P2O5 / acre)
0 – 20 60 – 100
20 – 40 0 – 60
> 40 0
Pasture and Grazing Management in the NW, 2010
Potassium
• Depletes Rapidly with Haying and/or Intensive Grazing
• Apply in Fall
• Low Levels Reduce Grass and Clover Vigor
General Potassium Recommendations for Grass and Grass-Legume Pastures
Soil Test K (ppm)
K2O Recommendation (lb/K2O / acre)
0 - 40 180 – 220
40 – 70 140 – 180
70 – 100 80 – 120
100 – 150 40 – 60
> 150 0
Pasture and Grazing Management in the NW, 2010
Sulfur
• Low Levels cause grasses and clovers to exhibit slow growth
• Small, yellow leaves on clovers is a sign of deficiency
Other Nutrients to Consider
• Lime
• Boron
• Molybdenum
Recommended Lime Application Rates (tons/acre) for Grass Legume Pastures on Acidic Soils
SMP Buffer pH Recommended Lime Application (tons/acre)
<5.5 4 to 5
5.5 – 5.8 3 to 4
5.8 – 6.1 2 to 3
6.1 – 6.5 1 to 2
> 6.5 0 to 1
Pasture and Grazing Management in the NW, 2010 From Hart, Pirelli, Cannon, and Fransen, 2000
Questions?
Discussion
Soil Fertility Critical Numbers
Nutrient Grass Alfalfa pH 5.3-8.5 5.8-8.4 (7.0) P 10 15 K 150 (?) 150 (?) S >9 >9 Ca 1,000 1,000 B N.A. 0.5 Zn 1.0 1.0 Mg 60 60 Cu 0.6 0.6 Mn 1.5 1.5 Cl ? ? Mo >1? >1? Sol Salts <1.0% <1.0% Se N.A. N.A. Na <10% <10%
Nutrient Distribution Cycling in a Grazed Pasture
• Pastures require less fertilization than field crops.
• Grazing livestock return as much as 85 to 95 % of the Nitrogen, Phosphorus, Potassium, and other nutrients consumed to the pasture through urine and dung.
• Nutrients are not distributed uniformly, however. They are concentrated next to the water source, shade, bedding areas, and trails.
Pasture and Grazing Management in the NW, 2010
Nutrient Distribution Cycling in a Grazed Pasture (cont.)
• After 4-5 grazing seasons, and P and K concentrations within 30 feet of water sources can be 5 times greater than other areas of the pasture.
• When grazing patterns remain unchanged for more than 20 years, increased P and K concentrations can be found up to 100 feet from the water source
Pasture and Grazing Management in the NW,
2010
Soil Fertility Management
• Sufficiency – Economic Response
• Maintain – What you remove, you put back
• Build the soil – Add back more than removed