Bermudagrass management for improved production AND stand maintenance Dr. Dennis Hancock Extension Forage Specialist UGA – Dept. of Crop and Soil Sciences Dr. Dennis Hancock Extension Forage Specialist UGA – Dept. of Crop and Soil Sciences

Outline Overview of Bermudagrass Forage Production Variety Selection Establishment and Grow-in Fertilization  Needs for production  Nitrate (NO 3 ) 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

Bermudagrass Hay Production – 2010 Breakdown of Projected Costs $105.27/ton

“All Kinds of Wacky”

Georgia “Hay” Prices BE

Soil Test and Follow Fertility Recommendations Sample hayfields every year and 1/3 of your pastures each year.

Costs Increase When Soil Fertility Decreases Recommended Rate of P & K Fertility NP2O5P2O5 K2OK2O Total Cost (lbs/acre) ($/acre) V. High 25000$ High Medium Low 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! 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: Nutrient Amt. Used Annually Unit Price Dec. in Efficiency Value of Decrease (Lbs/acre)($/lb)($/acre) N200$0.5535% -$39 P2O5P2O5 50$0.6250% -$16 K2OK2O150$0.6310% -$9 Total -$64

Hybrid Bermudagrass Yield Response to N Rate Hybrid Bermudagrass Yield Response to N Rate 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 Rates on Fuquay (F) and Carnegie (C) soils in Tifton Source: Dr. Bill Anderson, USDA-ARS Tifton

CP in Bermudagrass Forage as Effected by N Fertilization Source: Dr. Bill Anderson, USDA-ARS Tifton

Digestibility (IVDMD) of Bermudagrass Forage as Effected by N Fertilization Source: Dr. Bill Anderson, USDA-ARS Tifton

SPLIT YOUR NITROGEN APPLICATIONS! Long-term, this can increase yields by 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 Strategies MAMJJASO Green-up & After Each Cut

N Application Strategies MAMJJASO Green-up & After 2 nd Cut

N Application Strategies MAMJJASO 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 Days of Growth Growth of the Crop Nitrate Conc. in the Crop

Nitrate in forage fed to beef cattle. Forage Nitrate (ppm dry forage) Guidance < 4500Safe 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 < 9,000Limit to half (1/2) ration 9,000 to < 15,000Limit to third (1/3) ration 15,000 to < 18,000Limit to quarter (1/4) ration > 18,000Potentially lethal, very risky

N Concentration in the Forage Crop Days of Growth Nitrate Conc. in the Crop 4500 ppm Rec. Rate 2 x Rec. Rate 3 x Rec. Rate

N Concentration in the Forage Crop Days of Growth Nitrate Conc. in the Crop 4500 ppm Drought

N Concentration in the Forage Crop Days of Growth Nitrate Conc. in the Crop 4500 ppm Rec. Rate 2 x Rec. Rate 3 x Rec. Rate

Drought Severity and Nitrates in Bermudagrass

Growing SeasonAverage Confidence Interval Standard Error of the Mean parts per million (ppm) a † ± c± b± † Same letters within rows are not significantly different at P < 0.05.

Drought Severity and Nitrates in Bermudagrass Growing SeasonLow RiskModerate RiskHigh Risk (< 2500 ppm)( ppm)(> 4500 ppm) %11.2%8.5% (2034/2533)(284/2533)(215/2533) %19.6%15.1% (659/1010)(198/1010)(153/1010) %13.3%10.8% (659/869)(116/869)(94/869)

Additional Questions How much effect are high NO 3 having on reproduction? How successful can we be in preventing high NO 3 ? Will climate change inc. the incidence of this problem? Additional research is needed!

Eatonton 2008

Outline Overview of Bermudagrass Forage Production Variety Selection Establishment and Grow-in Fertilization Needs for production Nitrate (NO 3 ) accumulation in bermudagrass  Use of urea-based fertilizers  Needs for stand maintenance Harvesting methods Effects of Extended Grazing Burning

QUESTIONS? ASK-UGA1