1. How to produce high quality hay I: Forage species, harvest timing, and forage quality
Dennis Hancock, PhD.
Extension Forage Specialist
UGA – Dept. of Crop and Soil Sciences

2. What is the difference?

3. What is the difference?
Digestible energy
How much can be eaten

4. How do we get enough energy in the animal?
The animal eats more forage.
What is the physical limit?
Can a cow eat enough straw to meet her energy needs?
What forage the animal eats must be high in energy.
High digestibility -> High energy
Bottomline: Every bite has to count!

5. What is “high quality forage?”
Forage that is highly digestible (i.e., high TDN)
Large amounts of the forage can be consumed (i.e., high DMI).
Relative Forage Quality (RFQ) =
TDN * DMI/1.23
The vast majority of hay producers and certainly cattlemen believe that crude protein is the primary factor that influence hay quality. I believe that crude protein is the most OVERrated hay measure available. Think about the oh so popular Atkins diet. This is a diet where people consume large quantities of protein and restrict carbohydrate (calorie) intake to LOSE weight. Why would cattle or horses be any different. Crude protein tells you nothing about the energy content of hay. While protein can be related to the energy content of hay this often does not hold true, particularly when nitrogen fertilizer has been applied to the hay field or dry weather is present. Crude protein often doesn’t even indicate what quality the protein in the hay is. The protein could be in a highly useful form like amino acids or it may be bound due to heat damage and unavailable to animals. In a worst case scenario, some of the crude protein may even be HARMFUL to the animal because it is present in nitrates. In addition, the protein requirements of beef cows in particular are easily met with medium quality hay. A dry cow requires about 8% crude protein on a dry matter basis and even a lactating beef cow only requires around 12% crude protein. CP has traditionally been used as the default way to compare forage quality across species. That’s because it is related to the maturity of the crop that was cut. I’m not telling you that crude protein is unimportant as it is a useful measure and animal requirements must be met- it’s simply overutilized by most producers.

6. Relative Forage Quality (RFQ)75
100
125
150
175
200
225
Dairy, 1st 120 days
Dairy calf
Dairy, last 200 days
Heifer, 3-12 mo.
Stocker cattle
Weanling horse
Mature horse, int. work
Quality Required
Heifer, mo.
Lactating beef cow
Lactating mare
Mature horse, mod. work
Heifer, mo.
Dry cow
Mature horse, lt. work

7. Typical Range in Quality of Common Forages
Alfalfa
Other Legumes
Cool Season Annual Grasses
Quality Provided
Cool Season Peren. Grasses
Bermudagrass
Summer Annual Grass 75
100
125
150
175
200
225
Relative Forage Quality (RFQ)

8. Which Is The Better Hay?

9. Which Is The Better Hay?

11. What Affects Forage Quality?

12. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Fertilization
Provide fertilizer based on soil test recommendations
Variety
Use varieties that have proven to be higher in quality.

13. The Paradox of Forage Quality and Quantity
Digestibility & Palatability

14. Fescue Maturity- Effects on Yield and Protein
The same is true for tall fescue. As we progress from late boot to seed dough stage the yield per acre increases rapidly, but look what happens to crude protein level (add yellow line). Crude protein drops from 14% to 7% and is barely meeting animal requirements.

15. Fescue Maturity- Digestibility
Here’s a similar graph that shows what happens to the digestibility of that same tall fescue hay. Note that the bars represent total yield per acre and match the previous graph perfectly. If we harvest hay at late boot stage we get a little over 1.5 tons per acre of hay. The yellow part of the bar shows us that the animal is able to digest almost 1 ton per acre of that forage and utilize it for her energy requirements. The brown portion of the bar represents the undigested or “manure” portion of the hay produced (about 0.6 tons per acre). {Go through the rest of the bars and point out that even though YIELD increases that the amount of digested hay per acre does not- you are essentially baling up extra “manure” as the poorer quality hay has lower digestibility} It is interesting to point out that most of the hay baled in Georgia is at the hard seed stage (build last arrow) which is here on the graph…
Majority of hay harvested at hard seed stage
Only truly applicable with spring harvest

16. Bermudagrass Harvest Interval: Effects on Protein and Digestibility
Percent, %
Controlling the harvest interval and plant maturity of your hay operation is the simplest way to make a dramatic impact on hay quality. Note that this is very old data- over 40 years we have known this stuff!!! As we increase the harvest interval from 4 wks to 8 wks to 13 wks the crude protein of bermudgrass drops rapidly. Requirements of a mature dry cow are in the neighborhood of 8% so a supplement would be needed for 8 and 13 wk old hay. Also note the rapid decline in digestibility of the hay with older cuttings. We drop from 55% digestible to 45 (which is about equivalent to oat straw).
McCollough and Burton., 1962
DMI 11.9, 8.8, 9.5 lbs
ADG 1.2, .9, 0 lbs

17. Bermudagrass Harvest Interval: Effects on Yield and Protein
Hoveland et al., 1971

18. The Effect of Maturity on the Bottomline: Supplementing a Lactating Cow
Crop
Maturity CP
TDN
Supplement
Cost
-- % --
lbs/hd/day
$/hd/day
Bermudagrass
4 weeks
10-12
58-62 $0
6 weeks
8-10
51-55
4.8
$0.45
8 weeks
6-8
45-50
7.5
$0.72
+ ~$2.00/hd/d

19. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Fertilization
Provide fertilizer based on soil test recommendations
Variety
Use varieties that have proven to be higher in quality.

20. Typical Range in Quality of Common Forages
Alfalfa
Other Legumes
Cool Season Annual Grasses
Quality Provided
Cool Season Peren. Grasses
Bermudagrass
Summer Annual Grass 75
100
125
150
175
200
225
Relative Forage Quality (RFQ)

21. Quality Differences in the Major Forage Species
High
Production
Mod.
Production
Maint.

22. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Fertilization
Provide fertilizer based on soil test recommendations
Variety
Use varieties that have proven to be higher in quality.

23. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Fertilization
Provide fertilizer based on soil test recommendations
Variety
Use varieties that have proven to be higher in quality.

24. The Effect of Rainfall on DM Loss
Rainfall, in.
Scarbrough et al., 2005

25. Crop Moisture Lessens Rain Damage on Bermudagrass
DM Loss, %
76% Moisture, Not Significant.
Rainfall, in.
Scarbrough et al., 2005

26. Crop Moisture Lessens Rain Damage on Bermudagrass
NDF, %
76% Moisture, Not Significant.
Rainfall, in.
Scarbrough et al., 2005

27. The Effect of Rain on Tall Fescue Hay
No Rain
Rain Damage
Intake, % of b.w.
2.10
1.92
NDF, %
68.1
76.0
Digestibility, %
63.2
59.7
Turner et al., 2003

28. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Fertilization
Provide fertilizer based on soil test recommendations
Variety
Use varieties that have proven to be higher in quality.

29. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Variety
Use varieties that have proven to be higher in quality.

30. Yield and Digestibility of Bermudagrass Hybrids
This slide outlines the yield and quality of selected bermudagrass varieties at Tifton Ga. Note that all harvests were taken at the same time and all varieties were fertilized identically. Everything is set relative to Coastal, so anything above 100 yields more ( or has higher quality) than Coastal and vice versa. REMEMBER THIS WAS CONDUCTED AT TIFTON. Responses- particularly those of Tifton 44 and Tifton 85 will differ in North GA. Note that the yellow bars are all almost identical to Coastal suggesting that when harvested properly that variety makes little difference with quality. The two exceptions to this are Alicia and T 85. Alicia quality drops rapidly and can be much lower than other bermudagrasses. Tifton 85 quality is much higher than other varieties which makes this an excellent choice for producing high quality hay when South of I-20.

31. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Variety
Use varieties that have proven to be higher in quality.
Fertilization
Provide fertilizer based on soil test recommendations

32. Effect of N Rates on Bermudagrass CP & Digestibility
So what effect to fertilization have on the energy content of hay??? (Build yellow bar) Notice that as we go from 0 lbs to 1400!! Lbs of N per year that crude protein does go up (as expected). Notice that you can make crude protein content of hay almost anything you wish if you’re willing to deed the farm to the fertilizer company. But what is important is the red bar. Note that digestibility (or energy) in hay DOES NOT CHANGE regardless of what amount of nitrogen is put on. To increase caloric content of the hay we need to take an approach other than variety or fertilization…
Burton et al.

33. Effect of N Rates on Yield and CP of Bermudagrass
We’ve known for years that adding nitrogen to forage crops will improve yields (build first set of bars and talk about increasing annual nitrogen rate effects on yield). It is also true that higher nitrogen rates typically improve the amount of crude protein in the hay. However this can be misleading- think of the Atkins diet. This is a high protein diet that encourages weight loss!!!! Crude protein in hay has nothing to do with calories which are what cows are worried about…
Annual lbs N/Ac
Hoveland, 1971

34. Does fertility or harvest timing affect quality more?- Crude Protein
(4X as much N)
Bromegrass
Colovos et al. 1961

35. Does fertility or harvest timing affect quality more?- Digestibility
(3.8 X as much N)
Bromegrass
Colovos et al. 1961

36. Primary Factors Affecting Forage Quality
Recommendation
Plant Maturity
Cut bermudagrass every 4-5 wks; cut tall fescue in the boot or early head stage.
Forage Species
Use the highest-quality grass species that will persist in your environment.
Bale Storage
Protect bales from rainfall and weathering during storage (i.e., barn, tarp, etc.)
Rain During Curing
Avoid cutting if significant rainfall (> 0.50 inches) is predicted during curing.
Moisture at Baling
Allow forage to dry to the appropriate moisture (Round: 15%; Square: 18%)
Variety
Use varieties that have proven to be higher in quality.
Fertilization
Provide fertilizer based on soil test recommendations

37. Proper Maturity is the KEY!
Harvesting hay at the proper maturity is the only way to potentially bale high quality hay!
Fertilizer drives yield.
Economics should drive fertilization strategies, not quality goals.

38. Harvest Timing Recommendations
Hybrid Bermudagrass
1st cut at inches
Subsequent cuttings at week intervals
Tall fescue, ryegrass, orchardgrass, etc.
Spring cut at early flower stage
Mid to late boot stage for higher quality
Subsequent cuttings at inches (better quality)
Alfalfa
Spring cut at when 10-20% of plants are blooming
Cut at late bud – 10% bloom stage

39. QUESTIONS?