Bermudagrass management for improved production AND stand maintenance

Bermudagrass management for improved production AND stand maintenance

Dr. Dennis HancockExtension Forage Specialist

UGA – Dept. of Crop and Soil Sciences

Dr. Dennis HancockExtension Forage Specialist

UGA – Dept. of Crop and Soil Sciences

OutlineOutlineOverview of Bermudagrass Forage

Production

Variety Selection

Establishment and Grow-in

• Fertilization Needs for production Nitrate (NO3) accumulation in

bermudagrass Use of urea-based fertilizers Needs for stand maintenance

• Harvesting methods

• Effects of Extended Grazing

• Burning

Nutrients Removed/Acre With Bermudagrass Hay or Corn

Silage

Nutrients Removed/Acre With Bermudagrass Hay or Corn

Silage

Nitrogen Phosphate Potash Calcium Mag0

50

100

150

200

250

300 6 Tons Bermudagrass Hay30 Tons Corn Silage

lbs/

acre

rem

oved

$44.50

$19.36 $3.62

$3.41

$8.95

$21.17

$4.26

Fertilizer Fuel & Repairs Interest on Var. CostsPesticides Labor Fixed & Mgmt CostsLime

Bermudagrass Hay Production – 2010Breakdown of Projected Costs

$105.27/ton

“All Kinds of Wacky”“All Kinds of Wacky”

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

0.00

0.20

0.40

0.60

0.80

1.00Ammonium nitrateTriple-Super-phosphate (46%)Potassium chloride (60%)

Pri

ce($

/lb o

f N

, P2O

5, o

r K

2O)

2001 2002 2003 2004 2005 2006 2007 2008 20090

10

20

30

40

50

60

70

80

90

100

Hay

Pric

es in

Geo

rgia

($/t

on o

f hay

)Georgia “Hay” Prices 2001-

2009Georgia “Hay” Prices 2001-

2009BE

Soil Test and Follow Fertility Recommendations

Soil Test and Follow Fertility Recommendations

Sample hayfields every year and 1/3 of your pastures each year.

Costs Increase When Soil Fertility Decreases

Costs Increase When Soil Fertility Decreases

Recommended Rate of

P & K Fertility N P2O5 K2O

Total Cost

------------- (lbs/acre) ------------- ($/acre)

V. High 250 0 0 $187.50

High 250 30 150 318.59

Medium 250 60 200 352.17

Low 250 80 250 439.57

Assumptions: Using 32% UAN ($480/ton), DAP ($1300/ton), and Muriate of Potash ($780/ton).

Let’s assume P & K have been equally taken care of or equally neglected. So, let’s consider bermudagrass fertility.

DO NOT cut back on lime!DO NOT cut back on lime!

Get your priorities right!

1. Lime is still job #1.

Get your priorities right!

1. Lime is still job #1.

How Soil pH Affects Availability of Plant Nutrients

The difference of a soil pH of 5.6 vs. 6.2:

NutrientAmt. Used Annually

Unit Price

Dec. in Efficiency

Value of Decrease

(Lbs/acre) ($/lb) ($/acre)

N 200 $0.55 35% -$39

P2O5 50 $0.62 50% -$16

K2O 150 $0.63 10% -$9

Total -$64

Hybrid Bermudagrass Yield Response to N Rate

Hybrid Bermudagrass Yield Response to N Rate

0 25

50

75

100

125

150

175

200

225

250

275

300

325

350

375

400

425

450

475

500

525

550

575

600

625

650

675

700

725

750

775

800

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

Nitrogen Rate (lbs N/A)

Forage Yield(tons/A)

@15% mois-ture

Average or “Normal” Response

Hybrid Bermudagrass Yield Response to N Rate

Hybrid Bermudagrass Yield Response to N Rate

Yield Response of Tifton 85 to N Rates2004-2007 on Fuquay (F) and Carnegie (C) soils in TiftonYield Response of Tifton 85 to N Rates

2004-2007 on Fuquay (F) and Carnegie (C) soils in Tifton

200 300 400 500 600 7005

6

7

8

9

10

11

12

f(x) = − 0.130892857142857 x² + 1.46425 x + 6.71700000000001f(x) = − 0.180178571428572 x² + 2.08839285714286 x + 4.955T 85 F

lbs N/A

Yiel

d(d

ry to

ns/A

)

Source: Dr. Bill Anderson, USDA-ARS Tifton

CP in Bermudagrass Forage as Effected by N FertilizationCP in Bermudagrass Forage as Effected by N Fertilization

200 300 400 500 600 7000

2

4

6

8

10

12

14

16

18T 85 F T 85 C

lbs N

% P

rote

in

Source: Dr. Bill Anderson, USDA-ARS Tifton

SPLIT YOUR NITROGEN APPLICATIONS!SPLIT YOUR NITROGEN APPLICATIONS!

• Long-term, this can increase yields by 1200-2400 lbs/acre and increase NUE by 25-30% Especially important under extremes

Leaching Volatilization (in the case of urea-based

products) Late freeze Drought

N Application StrategiesN Application Strategies

M A M J J A S O

Green-up & After Each Cut

N Application StrategiesN Application Strategies

M A M J J A S O

Green-up & After 2nd Cut

N Application StrategiesN Application Strategies

M A M J J A S O

Green-up Only(Common Strategy with Poultry Litter)

Hybrid Bermudagrass Yield Response to N Rate

Hybrid Bermudagrass Yield Response to N Rate

N Concentration in the Forage Crop

N Concentration in the Forage Crop

Days of Growth

Gro

wth

of

the C

rop

Nitra

te C

on

c. in th

e

Cro

p

Nitrate in forage fed to beef cattle.

Nitrate in forage fed to beef cattle.

Forage Nitrate (ppm dry forage)

Guidance

< 4500 Safe to feed with adequate feed and water

4,500 to < 6,500 Safe under most conditions, but if feeding pregnant animals limit to half (1/2) ration

6,500 to < 9,000 Limit to half (1/2) ration

9,000 to < 15,000 Limit to third (1/3) ration

15,000 to < 18,000 Limit to quarter (1/4) ration

> 18,000 Potentially lethal, very risky

Subclinical Nitrate Toxicosis• Open cow that goes unexplained

• Lower milk production or gain.

N Concentration in the Forage Crop

N Concentration in the Forage Crop

Days of Growth

Nitra

te C

on

c. in th

e

Cro

p4500 ppm

Rec. Rate

2 x Rec. Rate

3 x Rec. Rate

N Concentration in the Forage Crop

N Concentration in the Forage Crop

Days of Growth

Nitra

te C

on

c. in th

e

Cro

p4500 ppm

Drought

N Concentration in the Forage Crop

N Concentration in the Forage Crop

Days of Growth

Nitra

te C

on

c. in th

e

Cro

p4500 ppm

Rec. Rate

2 x Rec. Rate

3 x Rec. Rate

Drought Severity and Nitrates in Bermudagrass

Drought Severity and Nitrates in Bermudagrass

Jul-0

3Ju

l-04

Jul-0

5Ju

l-06

Jul-0

7Ju

l-08

0

10

20

30

40

50

60

70

80

90

100D2-D4 D3-D4

Perc

ent o

f Geo

rgia

Severeor worse

Extremeor worse

Drought Severity and Nitrates in Bermudagrass

Drought Severity and Nitrates in Bermudagrass

Growing Season Average

Confidence Interval

Standard Error of the Mean

----------------------------------- parts per million (ppm) -----------------------------------

2003-06 512 a† ± 32.6 16.792007 1170 c ±200.1 102.092008 626 b ±110.4 56.33

† Same letters within rows are not significantly different at P < 0.05.

Drought Severity and Nitrates in Bermudagrass

Drought Severity and Nitrates in Bermudagrass

Growing Season Low Risk Moderate Risk High Risk

(< 2500 ppm) (2500 - 4500 ppm) (> 4500 ppm)

2003-06 80.3% 11.2% 8.5%(2034/2533) (284/2533) (215/2533)

2007 65.2% 19.6% 15.1%(659/1010) (198/1010) (153/1010)

2008 75.8% 13.3% 10.8%(659/869) (116/869) (94/869)

Additional Questions

How much effect are high NO3 having on reproduction?

How successful can we be in preventing high NO3?

Will climate change inc. the incidence of this problem?

Additional research is needed!

Eatonton 2008Eatonton 2008

AN4 U4 AN2 U2 ATU SU NSN ESN CON0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000 H1 H2 H3 H4

Nitr

ate

(NO

3-N

) Co

ncen

trati

on (p

pm)

OutlineOutlineOverview of Bermudagrass Forage

Production

Variety Selection

Establishment and Grow-in

Fertilization Needs for productionNitrate (NO3) accumulation in

bermudagrass Use of urea-based fertilizers Needs for stand maintenance

• Harvesting methods

• Effects of Extended Grazing

• Burning

QUESTIONS?QUESTIONS?

www.georgiaforages.com1-800-ASK-UGA1

www.georgiaforages.com1-800-ASK-UGA1