From Pasture Management Guide

1. From Pasture Management Guide

2. Growth follows a sigmoid curve Growth Dry weight accumulation Harvest Time increasing

4. Detergent Procedure to Partition Forages Forage Digest with neutral detergent soluble insoluble Cell Contentsproteinsstarchsugarsorganic acidspectin Hemicellulose, Cellulose, Lignin (NDF) Digest with acid detergent soluble insoluble Hemicellulose Cellulose and Lignin(ADF) Digest with 72% sulfuric acid insoluble soluble Cellulose Lignin ADL

5. Fig. 16.7. Digestibility ranges of major forage types. Dashed lines illustrate forage digestibility levels needed to meet energy requirements of different classes of beef cattle (Riewe, 1981 and Reid et al., 1988). From Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed.

6. Stage of Maturation: Fig. 16.8. Maturity effects on alfalfa quality. From Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed.

7. Leaves vs Stems Fig. 16.6. Forage quality analysis of leaf and stem tissue from alfalfa and timothy growing together in a mixture (Collins, 1988). From Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed.

8. Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed.

9. Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed. When K increases, winter survival increases. When N increases, winter survival decreases.

10. Introduction to Forages

11. V.G. Allen, C. Batello, E.J. Berretta, J. Hodgson, M. Kothmann, X. Li, J. McIvor, J. Milne, C. Morris, A. Peeters, M. Sanderson. 2011. An international terminology for grazing lands and grazing animals. Grass and Forage Sci. 66: 2-28 DOI: 10.1111/j.1365-2494.2010.00780.

12. Pastureland land devoted to the production of indigenous or introduced forage for harvest primarily grazing. Pastureland generally must be managed to arrest successional processes. Rangeland land on which the indigenous vegetation is predominately grasses, grass-like plants, forbs, or shrubs and is managed as a natural ecosystem. Often a semi-arid region. If plants are introduced, they are managed as indigenous species. What is “forage”?

13. What is “forage”? Forage - edible parts of plants, other than separated grain, generally above ground, that can provide feed for grazing animals, or can be harvested for feeding. • Woody • Herbaceous, “herbage” non-woody • Grass - Poaceae family • Grass-like - vegetation is similar to grass in appearance; member of the Cyperaceae (sedges) and Juncaceae (rushes) families • Forb - any herbaceous broadleaf plant that is not a grass or is not grass-like • Legume - member of the Fabaceae family • Non-legume

14. What is “forage”? • Pasture, animal harvest, grazing, harvested plant material is 80% moisture • Hayfield, mechanical harvest, storage • Silage/haylage - wet; wilted; chopped; fermented, 60 - 40% moisture • Hay - dry; wilted; baled, <20% moisture, • Pellets - dehydrated; quickly dried at 300-1000 C; ground; pellet or cube

15. What is “forage”? • Diverse plant material within a field; diverse species: grasses, legumes, forbs; diverse canopy heights; diverse rooting depths; diverse maturations, i.e. mimicing the prairie • Few plant species; a grass and a legume species; diverse plant structure; not diverse maturation • Monoculture; one species, often alfalfa

16. What is “forage”? Annual: one year, harvested immature, typically harvested for grain, for ex. small grain haylage/silage, corn silage, sorghum silage, sorghum-sudangrass silage Biennials: Brassica spp, (turnips) grazed the first year while vegetative Perennials: multiple year life span

17. What is “forage”? What does the consumer (animal) want? • Maximum quantity, dry matter/feeding • Maximum quality, nutritive value The goal of the producer: • Maximum quantity (yield), dry matter/A • Maximum quality, nutritive value • Stand persistence, perennial stand remains healthy over years

18. From Pasture Management Guide

19. Seasonal growth patterns in forages

21. Growth/Yield is a result of photosynthesis • Photosynthesis, capturing sunlight which used as the energy to fix CO2, produce sugar, that is used for growth, production of dry matter, yield • Green tissue captures sunlight, both leaves and stems • Capturing sunlight so that no sunlight reaches the soil surface, inhibiting low growing forages in a mix, forage stand not reaching its potential

22. Growth follows a sigmoid curve Growth Dry weight accumulation Harvest Time increasing

23. Sugar production leads to dry matter accumulation cell contents Sugar fructan or starch cell wall Hemicellulose Cellulose Lignin growth, excess is stored structure

24. Defoliation – removal of foliation (harvest) (leaves, stems) Due to: • Mechanical harvest • Grazing • Other organisms, animals, diseases • Fire • Chemicals, herbicides • Extreme cold temperatures, winter

25. After defoliation: • For one to two weeks, above ground growth has priority • Root growth stops, fine roots and root hairs may die • Nutrient uptake declines • N-fixation is greatly reduced or ceases

26. Regrowth follows a sigmoid curve Growth Dry weight accumulation Harvest regrowth Defoliation Time increasing

27. The ability to fully recover will depend upon: • Availability and type of meristematic tissue • Remaining leaf area • Carbohydrate reserves, nutrient levels • Frequency of defoliation • Environmental conditions

28. Remaining leaf area (LA) • LA location of sugar production, the amount of sugar produced is proportional to the leaf area, sugar is needed for growth • Height of cutting or bite, the more LA the faster the recovery, less the “yield” • For growth the plant uses CHO reserves: base of the stem, crown, rhizomes, roots • Initial spring growth, no LA, CHO reserves only • The level of N in reserves influences initiation of regrowth, amino acids are used

29. Frequency of defoliation • As frequency of defoliation increases, the time between harvest decreases • Less regrowth has accumulated, lower yields • The ability for CHO reserves to completely replenish decreases • Resulting in less yield, slower regrowth, weakened plants, dead plants

31. Figure 2. Changes that occur in dry-matter yields and CHO reserves during growth periods of an alfalfa crop.

32. Effect of harvest frequency on yield.

33. Regrowth follows a sigmoid curve Growth Dry weight accumulation Harvest regrowth In IA: 2.5 weeks, May-June 5+ weeks, Aug-Sept Time increasing

34. What does the consumer (animal) want? • Maximum quantity, dry matter/feeding • Maximum quality, nutritive value The goal of the producer: • Maximum quantity (yield), dry matter/A • Maximum quality, nutritive value • Stand persistence, perennial stand remains healthy over years Amount of nutrients and the ability to get to the nutrients (digestibility of the plant material)

35. Structural sugars cell contents Sugar fructan or starch cell wall Hemicellulose Cellulose Lignin

36. Detergent Procedure to Partition Forages Forage Digest with neutral detergent soluble insoluble Cell Contentsproteinsstarchsugarsorganic acidspectin Hemicellulose, Cellulose, Lignin (NDF) Digest with acid detergent soluble insoluble Hemicellulose Cellulose and Lignin(ADF) Digest with 72% sulfuric acid insoluble soluble Cellulose Lignin ADL

37. Digestibility • Measured using bioassays • In situ, or in vivo in the animal, using fistulated animals; digestion trials, apparent dry matter digestibility, (DM intake - DM out)/ DM intake • In vitro, in test tube with rumen fluid, outside the animal, IVDMD (in vitro dry matter disappearance) • Calculated • Total digestible nutrients (TDN), summation of the digestibility of the different components • DDM (digestible dry matter), DDM% = 88.9 - (0.779 x ADF%)

38. Forage quality needs depend upon: • Animal species • Purpose or function of the the animal • Lactation; greatest nutrient need • Growth, meat; younger animals > older • Stage of development • Growing, 1-1.5 maintenance • Lactating, 2-2.5x maintenance • Maintaining

39. Fig. 16.7. Digestibility ranges of major forage types. Dashed lines illustrate forage digestibility levels needed to meet energy requirements of different classes of beef cattle (Riewe, 1981 and Reid et al., 1988). From Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed.

40. Plant Species • Protein: • legumes > cool season grasses > warm season grasses • N fertilization can increase CP in grasses. • Fiber: • warm season grasses > cool season grasses > legumes • Minerals: legumes > grasses • Varietal differences: not much selection is based on quality; more on yield, stand persistence, pest resistance

41. Stage of Maturation: Fig. 16.8. Maturity effects on alfalfa quality. From Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed.

42. Stage of Maturation • Change in maturity: • the rate of change is species dependent, digestibility of grasses declines faster than the digestibility of legumes • quality of stems declines with age, quality of leaves remain fairly constant

43. Leaves vs Stems Fig. 16.6. Forage quality analysis of leaf and stem tissue from alfalfa and timothy growing together in a mixture (Collins, 1988). From Forages Vol. I, An Introduction to Grassland Agriculture, 6th ed.

44. Leaf:stem ratio • Amount of DM from the leaf portion of the forage compared to the amount of DM from the stem portion • Leaves have higher quality, 2x more CP in leaves in than stems, less structural CHO (fiber) in leaves than stems • Ratio is dynamic, changes over time; stem leaf • Harvest, store, and feed LEAVES

45. What is the cost of poor quality forage?

46. Adapted from data by Mertens, 1985; Pioneer Forage Manual NDF is a measure of quality. As percent fiber increases, intake decreases, leading to a decrease in animal production.

47. http://www.uwex.edu/ces/forage/pubs/auction.htm As the forage quality increases, the price paid increases. High quality forage has a higher value.

48. Milk production Increase = $400 profit Milk production (lb/acre) Milk production increases, profits increase with higher quality hay.

49. Forage quality decreases with plant maturation. • Daily gain (lb of gain per day) decreases with decreasing forage quality. • Concentrate:forage ratio increases with forage age, resulting in increase costs.

50. Can I determine forage quality by just looking at it?In the field before harvest?In storage?