1. FIRST Aid for Drought-Stressed Forages Part I: Drought Management Plan
Dennis Hancock
Extension Forage Agronomist
Crop and Soil Sciences

2. Too little, too late. “Average” Difference
Georgia Automated Environmental Monitoring Network (

3. May
June
Pasture
Conditions
-2006
July
August
September

4. A few assumptions… Delayed decisions led to overgrazing
Body condition scores slipped (< 5)
Likely poor conception rate!
Problem is worse where Tall Fescue is the base
A lot of poor-quality and/or expensive hay was fed
Difficulty in fall establishment

5. On the bright side… A chance to evaluate your stocking rates…
Good time to apply lime/gypsum and P/K fertilizer
If cattle are already in a sacrifice area
Ensure that P/K addition is not in sensitive areas
Make preps for other renovation

6. First Aid for Drought-Stressed Forages
First, do no harm!

7. Overgrazing During Drought
Plants slow way down and go dormant
Drought rarely kills most pasture species.
But can if combined with poor fertility, overgrazing, or pests…
Competition w/ warm-season species
Overgrazing reduces reserves (carbohydrates) and root growth

8. First Aid for Drought-Stressed Forages
First, do no harm!
Recognize early
De-stock
De-populate
Set up sacrifice areas
Best Defense is a Good Offense.

9. No such thing as a good “quick-fix”.
"FIRST" Aid
ERTILITY
NSECT CONTROL
FIRST
ISK MANAGEMENT
PECIES
IMING

10. No such thing as a good “quick-fix”.
ERTILITY
FIRST

11. Drought Tolerance Species Water Use Efficiency Max. Root Depth
DM lbs/inch
inches
Coastal Bermudagrass
1646 78
Pensacola Bahiagrass
1194 79
Tall Fescue
1064 48
Ladino Clover
480 38
Red Clover
436 45
From: Southern Forages, as adapted from Doss et al. (1960; 1962; 1963)

12. Low Soil pH

13. Low Soil pH = Aluminum Toxicity

14. Soil Acidity and CEC Strength of cations:
pH = 7.0
BS = ~ 50%
pH = 6.0 H+ K+
Ca2+
Mg2+
Soil
BS = 0%
Al3+
pH = 4.5 H+
Soil
Ca2+ K+
Mg2+
Soil
BS = 100%
Strength of cations:
Al3+ > H+ > Ca2+ > Mg2+ > K+

15. Very Slightly Alkaline
How Soil pH Affects Availability of Plant Nutrients
Very Slightly Acid
Very Slightly Alkaline
Strongly Acid
Medium Acid
Slightly Acid
Slightly Alkaline
Medium Alkaline
Strongly Alkaline
disk 10 pH

16. + CaCO3 Ca2+ + CO3 Soil Soil HCO3 + Al(OH)3 CaCO3 pH = 4.5 Al3+ Al3+

17. Lime Quality Rule: At least 90% must pass a 10 mesh sieve. Sieve Size
% of total
≤ 10 mesh 12
10-20 mesh 17
20-35 mesh 55
≥ 35 mesh 16

19. Plants very sensitive to acidity pH 6.5-7.0 required
Alfalfa
Barley
Sweet clover

20. Slight tolerance to acidity pH 6.0-6.5
Corn
Crimson clover
Dallisgrass
Ladino clover
Orchardgrass
Red clover
Ryegrass
Sorghum-sudan
Wheat

21. Moderate Tolerance to Acidity pH 5.5-6.0
Bahiagrass
Bermudagrass
Lespedeza
Oats
Pearl Millet
Tall fescue
Vetch
(Perennial Peanut)

22. Potash also determines competitiveness of some species
Leafspot and winterhardiness

23. Nutrients removed per acre with bermudagrass hay or 500 lb animal
Adapted from S. Forages 3rd Ed.

24. Efficiency of Four-legged Manure Spreaders
White et al., 2001 J. Environ. Qual. 30:2180–2187

25. Thou Shalt Soil Test
Sample 1/3 of your pastures each year.

26. Thou Shalt Soil Test Most common cause of poor establishment:
Soil pH and/or fertility is too low.
Most common cause of poor persistence:
Most common cause of poor drought tolerance:

27. No such thing as a good “quick-fix”.
ERTILITY
NSECT CONTROL
FIRST

28. Fall Armyworm Fall armyworm infestations can be a problem anytime,…
But, the effects are most devastating in drought years.

29. Fall Armyworm
ACES – ANR-1019

30. Fall Armyworm

31. Application if above threshold (>3 larvae per ft2)
Fall Armyworm Control
Application if above threshold (>3 larvae per ft2)
Sevin
Tracer
Lannate (bermudagrass only)
Dimlin

32. No such thing as a good “quick-fix”.
ERTILITY
NSECT CONTROL
FIRST
ISK MANAGEMENT

33. -------------------- Dry lbs/ac --------------
Emergency Forage Base
2005 Total (3 cuts)
2006 Total (4 cuts)
SORGHUM/SUDAN
Dry lbs/ac
SS 211A
26813 a
12944 a
Summergrazer III
22053 b
11405 b
SS 220 BMR
19246 c
10731 b
PEARL MILLET
Tifleaf 3
17441 a
10728 a
SS 635
17273 a
9309 b
Pennleaf
16602 a
8826 b

34. Nitrate in forage fed to beef cattle.
Forage Nitrate
(mg/kg 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 restrict 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, dilute carefully

35. Feeding hay during the drought -
Hay value during drought year: % more

36. Drought Risk Management Plan
Have an emergency forage base
Don’t depend on hay stocks
Supplement to stretch hay
Cull following a priority list

37. No such thing as a good “quick-fix”.
ERTILITY
NSECT CONTROL
FIRST
ISK MANAGEMENT
PECIES

38. Legume Persistence Species/Cultivars Year-to-year variations
Drought
Grazing pressure
Temperature
Soil Conditions
Competition

39. Species/Cultivars Red Clover (Cimarron Plus, Redland Max, Cherokee)
Alfalfa (Alfagraze, Bulldog 505, Amerigraze 702, Bulldog 805)
White Clover (Durana, Patriot)

41. No such thing as a good “quick-fix”.
ERTILITY
NSECT CONTROL
FIRST
ISK MANAGEMENT
PECIES
IMING

42. Drought Recovery Allow the pasture to recover Not too soon!
Leave sufficient grazed stubble
Tall Fescue: in.
Bermudagrass: ~2 in.
Not too soon!
Target height to start grazing
Tall Fescue: in.
Bermudagrass: in.
Reintroduce pastures slowly

43. Effect of Grazing on Recovery
Grazing is SELECTIVE defoliation
Unlike mowing this may allow greater pressure to be placed on a single forage species
Shift competitive advantage toward unfavorable species
Can alter selectivity with animal species, stocking rate and timing

44. SUMMARY
ERTILITY
NSECT CONTROL
FIRST
ISK MANAGEMENT
PECIES
IMING

45. Keys to Pasture Survival…
FIRST
Maintain soil pH: 6.2 – 6.5
Maintain P/K levels
P for energy maintenance and root growth
K for persistence (esp. legumes & Bermudagrass)

46. Keys to Pasture Survival…
FIRST
Anticipate insect damage
Spray if thresholds have been exceeded.

47. Keys to Pasture Survival…
FIRST
Follow your drought plan
Early Recognition
Set up sacrifice areas
Save Hay

48. Keys to Pasture Survival…
FIRST
Integrate an emergency forage base
Monitor nitrate levels
Maintain perennial species that will buffer against droughts.

49. Keys to Pasture Survival…
FIRST
Leave some stubble
Reintroduce pastures slowly

50. QUESTIONS?