Notes on Forages, Silage, and Nutrition
Straw vs Hay
- Straw vs hay is a common source of confusion. Straw is thicker, with more stalk, higher structural carbohydrates, and very little nutrient value.
- Halloween decorations often use straw bales; decorative straw is very dry and brittle and lacks thickness.
- Hay is leafier and leakier, with slower-curving blade structure compared to the rigid, board-like appearance of straw.
- Visual cues: hay shows more leaf content; straw appears stiffer and more fibrous.
Cottonseed and fiber sources
- Whole cotton seeds are high in energy and protein.
- Cottonseed hulls (hulls) are a good fiber source.
- When harvesting cottonseed, hulls may be removed; hulls contribute dietary fiber.
Bale production and baling machinery (overview)
- Baler operation involves pulling cut forage into a chamber using belts and rollers.
- A tractor provides PTO power to drive the baler; belts and rollers form and compress the bale.
- Tension on belts allows some flex; bale formation relies on rakes in the bottom portion that lift and toss grass upward into the wrap area.
- As grasses are fed in and wrapped, the bale forms progressively until a switch detects proper belt tension and width, triggering wrapping mechanism.
- If using a string bale, a string is wrapped around the bale; if using net wrap, a plastic net wrap (fishnet-like) is wrapped multiple times to secure the bale.
- The process creates large round bales typical of field production.
Cutting, mowing, and chopping for baling
- Grass is cut with a sickle-bar cutter to around 3 inches tall; mulching blades chop further to 2 inches depending on setup, leaving intact tops and little “top-hatted” pieces that are easier to bale.
- When mowing a lawn, small long pieces may remain; a well-tuned cutter produces shorter pieces that bale more easily.
- Longer pieces are easier to bale and promote better mastication for ruminants.
Windrows and baler path
- After cutting and laying on the field, the mower operator forms windrows (rows of cut forage).
- A tractor with a baler passes along the windrows in a zigzag to ensure an even bale fill.
- A beeping signal in the tractor indicates the bale is full and ready to wrap.
- Bale formats:
- String-wrapped round bales.
- Net wrap (plastic net) bales.
- A baleer may use wire fencing and spikes to move bales; individual bale wrappers can wrap a single bale.
- Moving hay with a spear (large spike) requires caution: holes in plastic create oxygen entry and spoilage; repairs may involve duct tape on damaged wraps.
- Hands-on handling: place bales down gently; stack like marshmallows to minimize damage and ensure stability.
Moisture management and drying targets
- Typical moisture target before wrapping/baling: about 20% moisture or 80% dry matter (DM).
- Starting moisture can be very high (up to 90% moisture on the ground), so drying occurs after cutting.
- Drying time varies; 2–3 days may be enough to reach 15% moisture in favorable conditions for bale processing.
- Moisture impacts fermentation risk: moist bales ferment and can heat up, potentially igniting the bale stack or barn if in an enclosed space.
- Center of stacked bales in a barn may heat during fermentation; improper ventilation increases fire risk.
Fermentation risks and safety
- Wet bales ferment anaerobically; fermentation generates heat. If heat accumulates, it can ignite surrounding bale material and structures.
- A stack could be 20 feet high and 75 feet long; improper stacking and moisture can escalate risk quickly.
- Moisture management is critical for both safety and nutrient preservation.
Grass varieties and bloat risk
- Bermuda grass and Johnson grass are common forages; clover (red, white, and crimson) also appears in spring.
- Legumes like clover can cause bloat (frothy bloat) in ruminants when consumed in certain grazing scenarios.
- Bloat risk is a practical consideration in grazing and feeding management.
Moisture-based dry matter and nutrition basics
- Example moisture/dry matter relationships:
- 15% moisture corresponds to 85% DM.
- 20% moisture corresponds to 80% DM.
- Initial cut forage can be very moist; DM increases as it dries.
- For baleage/silage, high-moisture forage is packed and sealed to create anaerobic conditions; spoilage must be avoided by excluding air.
Silage versus baleage (high-moisture feeds)
- Silage/baleage are high-moisture forages preserved via fermentation in anaerobic conditions.
- Silage is made in silos or pits (concrete or earth) and sealed with plastic and tires to keep air out.
- Baleage refers to wrapping a bale in plastic and storing it similarly to silage, but in bale form.
- Silage pits or silos are designed to limit air exposure; sealing is essential to prevent mold and spoilage.
- Baleage produces a more stable product than straight green forage if packed and sealed correctly.
Silage pits, silos, and packaging options
- Concrete-walled silos and above-ground pits are common; moisture control and cleanliness are important.
- Pits are filled with chopped green material, compacted to minimize air pockets, and sealed with plastic and tires to ensure fermentation.
- Alternative packaging includes:
- Tube-wrapped bales (ag bags): long tubes where forage is packed and air-excluded; only the exposed end touches air during feeding.
- Ag bags: large rolls used to create long, continuous silage tubes.
- Individual bale wrappers: wrap each bale separately for longer shelf life.
- Face management: when accessing silage, maintain a clean, flat face to minimize surface area exposed to air and spoilage.
Green chop and pasture-use options
- Green chop involves harvesting forage from pasture and delivering it fresh to livestock for higher moisture and nutrient content.
- After feeding, scraps are cleaned up and the process can repeat to provide fresh forage when fencing is limited or pastures are used for feeding.
- Green chop supports efficient pasture use and provides forage with higher moisture and nutrients than dry hay.
Pasture management and grazing strategies
- Strip grazing or limit grazing uses fences to control how much forage animals access at one time.
- Move fences or allow animals to move themselves to prevent overgrazing and to maximize long-term pasture productivity.
- Overgrazing reduces future yield; planned grazing distributes pressure and extends forage availability.
Hay storage and quality control
- Proper hay storage prevents moisture pooling and leaks that promote mold and spoilage.
- Water pooling or leaks in storage areas can drastically reduce hay quality and increase waste.
- Storage conditions (dry, clean, well-ventilated) are essential for maintaining nutritional value.
Economics and feed quality factors
- Hay price varies by quality and region; common ranges include around $30–$35 per bale for average hay and $50–$60 for higher-quality, fertilized, cleaner hay.
- Fertilization and pest control improve yield and quality, potentially increasing price.
Silage and forage processing details
- Silage faces: a flat, well-packed face minimizes surface area and spoilage; a clean face is a sign of good management.
- Digesting forage involves changing surface area by breaking down long pieces into smaller ones to increase digestibility, similar to making better ice pellets in a fast-food context.
Forages versus roughages and nutrient discussions
- Roughages: bulky feeds, typically higher fiber and more structural; often drier and less digestible.
- Forages: usually higher moisture content, at least 18% crude fiber, more digestible than roughages, and require different handling in rations.
- In dry matter calculation, moisture dilutes nutrients; balancing nutritional formulations requires accounting for water content.
Protein sources, energy sources, and typical diets
- Soybean meal (SBM) is a common high-protein feed, typically around $$CP ext{(crude protein)} ext{ } \