Photo Credit: U.S. Department of Agriculture | Flickr | CC BY 2.0 | no changes made

Forage is the foundation of livestock nutrition, providing essential nutrients, fiber, and energy for animals to thrive. Whether fresh pasture or harvested hay, high-quality forage supports animal health, reduces feed costs, and promotes sustainable farming practices. But not all forage is created equal—understanding what makes good forage, how to evaluate quality, and which types best suit different livestock species is key to optimizing performance and profitability.

This e-book explores the benefits of forage-based diets, how to identify top-quality fresh and stored forages, and the specific needs of various livestock, from cattle and sheep to goats and horses. Whether you’re a seasoned farmer or just starting, this guide will equip you with the knowledge to make the most of your forages and keep your livestock thriving.

Benefits of Allowing Livestock to Forage

Improved Animal Health

• Provides a diverse, nutrient-rich diet, enhancing overall nutrition.
• Reduces stress and promotes natural grazing behavior.
• Lowers the risk of digestive issues compared to grain-based diets.

Cost Savings

• Reduces reliance on purchased feed, cutting feed costs.
• Lowers labor and equipment expenses associated with feed distribution.

Soil & Pasture Health

• Encourages natural manure distribution, improving soil fertility.
• Supports regenerative agriculture by enhancing soil structure and microbial life.
• Prevents overgrowth of unwanted vegetation through controlled grazing.

Sustainability & Environmental Benefits

• Reduces reliance on synthetic fertilizers and grain production.
• Helps control erosion and improves water retention in the soil.
• Lowers the carbon footprint of livestock farming.

Better Meat & Dairy Quality

• Grass-fed livestock often produce higher-quality meat and milk with better fatty acid profiles.
• Natural forage diets can enhance flavor and nutritional value.

Photo Credit: Paul VanDerWerf | Flickr | CC BY 2.0

Principles to Consider When Selecting Forages

Selecting the right forages for livestock production requires a systematic approach that balances multiple factors. Forage selection should be tailored to the specific needs of different livestock species, as cattle, sheep, goats, and horses all have unique dietary requirements. Still, there are general parameters that apply to all livestock.

This section outlines the key principles to consider when making forage selection decisions.

Nutritional Quality

Growing and managing top-notch forages means they can make up most or even all of what your animals eat. That's why picking the right forage or forage mix is so important - you need options that nutritionally deliver your animals' needs. 

Production Yield and Longevity

Choosing forages that produce adequate amounts of dry matter and grow reliably throughout the season is just as important as nutrition. You need plants that yield enough to feed all your livestock, with growth patterns that keep your pasture productive season after season.

Climate Compatibility

When selecting forages, matching them to your climate conditions is essential. Choose cool-season or warm-season species based on your temperature zone, and ensure the variety aligns with your growing season length and frost-free period. 

Consider precipitation patterns, opting for drought-tolerant species in arid areas or moisture-adapted varieties in humid regions. In colder climates, prioritize winter hardiness; in hotter areas, focus on heat tolerance to ensure summer persistence.

Soil Factors

Soil characteristics play a crucial role in forage selection. Different species thrive in clay, loam, or sandy soils, so matching forage to your soil type is essential. Drainage is another key factor—some species tolerate wet conditions, while others require well-drained soils. Soil pH also influences growth, so choose varieties suited to acidic, neutral, or alkaline conditions. 

Consider fertility requirements, as some forages need nutrient-rich soils while others perform well in low-fertility environments. In areas with high salinity, salt-tolerant species are essential for productivity. Finally, soil depth and topography should be accounted for, as shallow soils, slopes, and aspect differences can impact forage establishment and yield.

Maintenance Demands

Forage management requires careful consideration of several factors to ensure long-term productivity. 

Fertility requirements vary, with grasses often needing consistent nitrogen inputs for optimal growth. Pest management is also crucial, as different species have varying susceptibility to insects, diseases, and other threats. Understanding irrigation needs helps determine whether a forage is drought-tolerant or dependent on supplemental water. 

Additionally, harvest flexibility should be evaluated, considering whether the forage is best suited for grazing, haying, or silage. Lastly, some species require frequent stand renovation, while others persist with minimal maintenance, making long-term planning essential.

Economic Considerations

It's essential to consider the overall return on investment, balancing yield potential against input costs. Certain forages may offer unique market opportunities, catering to specialized markets or uses. Risk assessment is also key, as some species are more resilient to unpredictable weather conditions than others. Evaluating multi-year productivity helps determine whether annual crop costs outweigh perennials' long-term benefits. 

Finally, equipment compatibility should be considered to ensure efficient farm resource use and minimize additional investments.

Grasses vs. Legumes: Which Forage Type Should Dominate Your Pasture?

Single-species plantings of either grasses or legumes come with their own set of benefits and challenges. 

Pros of Forage Grasses

✓ High fiber content

✓ Longer growing season

✓ Tolerant of frequent, close grazing

✓ Establish quickly

✓ Tolerant of a variety of soils

✓ Better drought tolerance over legumes

✓ Can be grazed or used for hay

Cons of Forage Grasses

✗ Lower crude protein 

✗ Less tolerant of trampling

✗ Lower yields

 

Photo Source: Jeffrey Surianto | Pexels

Pros of Forage Legumes

✓ High in crude protein

✓ Improved palatability and digestibility

✓ Nitrogen fixation lowers input costs

✓ Useful for grazing or hay

Cons of Forage Legumes

✗ Less tolerant of heat, cold, and drought

✗ More intense management requirements

 

Photo Source: Wikimedia Commons

Multi-Species Pasture Advantages

Rather than planting single-type pastures, many successful livestock operations are switching to mixed forage systems that combine various grasses and legumes. This diversity delivers several practical benefits for your operation: 

• Higher total forage production per acre
• Natural weed suppression as multiple plant types fill available space
• More consistent forage availability throughout the growing season
• Better resilience when facing drought, excess rain, or temperature extremes
• Lower fertilizer costs since legumes naturally add nitrogen to the soil

Choosing Annuals vs. Perennials

Annual forages complete their entire lifecycle—from germination to seed production—within a single growing season. They require replanting each year to maintain forage production. Examples include annual ryegrass, small grains (oats, wheat, rye), sorghum-sudangrass hybrids, and annual legumes like crimson clover.

Perennial forages persist for multiple years from a single establishment, with lifespans ranging from 3-5 years for some legumes to 10+ years for well-managed grass stands. Notable perennials include alfalfa, tall fescue, orchardgrass, timothy, and white clover.

Comparative Advantages and Limitations of Annual Forages

Advantages:

✓ Higher yield potential within their growing season

✓ Greater flexibility in crop rotation systems

✓ Ability to fill seasonal forage gaps

✓ Quick establishment and production

✓ Can be used as emergency forage during shortages

✓ Allow for rapid adaptation to market changes

✓ May provide better weed suppression during establishment

 

Limitations:

✗ Higher recurring establishment costs (seed, labor, fuel, equipment)

✗ Increased soil disturbance and erosion risk

✗ Greater vulnerability to establishment failures

✗ Higher year-to-year variability in production

✗ More intensive management requirements

✗ Limited contribution to long-term soil health compared to perennials

 

Photo Credit: NRCS Oregon | Flickr | CC BY-ND 2.0 | no changes made

Comparative Advantages and Limitations of Perennial Forages

Advantages:

✓ Lower long-term production costs when amortized over multiple years

✓ Reduced soil erosion and improved soil structure

✓ Extended growing seasons with earlier spring and later fall production

✓ Deeper root systems enhancing drought tolerance

✓ Greater carbon sequestration and soil organic matter contributions

✓ Reduced annual labor and equipment demands

✓ More stable year-to-year production

 

Limitations:

✗ Slower initial establishment period

✗ May have lower peak production compared to annuals

✗ Less flexibility to change production systems

✗ Potential for stand deterioration over time

✗ May require periodic renovation

✗ Can be more challenging to maintain optimal forage quality as stands mature

 

Photo Credit: Matt Lavin | Flickr | CC BY-SA 2.0 | no changes made

When to Choose Each Type

Choose annual forages when:

• Needing quick production after a crop failure
• Filling seasonal gaps in perennial forage systems
• Testing new forage options before larger-scale commitment
• Transitioning between perennial stands
• Operating in rental land situations with short-term agreements
• Requiring specific seasonal production windows
• Implementing rotational benefits in row crop systems

 

Choose perennial forages when:

• Seeking long-term stability in forage systems
• Establishing pastures on erodible or marginal lands
• Focusing on soil health improvement
• Minimizing annual establishment operations
• Managing lands less suitable for cultivation
• Developing low-input sustainable systems
• Creating wildlife habitat alongside forage production

Planning for Year-Round Forages

Regardless of your locale, you can assemble an extended-season forage plan to feed your livestock as long as possible, if not year-round. Forages for spring and fall pastures include cool-season grasses and legumes such as clover.

1. Identify what forages are available for grazing each season.
• Spring pastures include cool-season grasses and legumes like red and white clover and hairy vetch.
• Summer pastures include warm-season grasses and legumes like lespedeza and alfalfa.
• Fall forages include cool-season grasses, wheat, oats, and alfalfa.
• Winter forages include silage, hay, and crop residues.
2. Choose one or two primary forages based on local climate and soil conditions to meet your production needs.
3. Improve management practices (e.g., fertilization, watering) to extend the existing forage’s grazing season.
4. Add complementary forages to fill in seasonal gaps. 

Grazing Strategies for Better Pasture Efficiency

Livestock may graze continuously across the entire pasture or be rotated through different sections, allowing forage to recover before being grazed again.

Continuous Grazing

Continuous grazing is a single-pasture system where livestock have unrestricted access to the entire grazing area throughout the season. Typically, all animals are turned out at once, with no designated rest periods for forage recovery.

This system is easy to manage and requires minimal investment, but it often leads to overgrazing, reducing both forage quality and quantity. Uneven manure distribution, persistent weed growth, and the need for lower stocking rates to maintain sufficient forage are common challenges associated with continuous grazing.

Rotational Grazing

Rotational grazing is a pasture management system where livestock are moved between multiple grazing areas, allowing forage in previously grazed sections to recover before being used again. This method promotes healthier pastures by preventing overgrazing, improving forage regrowth, and enhancing soil health. By controlling grazing pressure, rotational grazing helps maintain a diverse and nutrient-rich forage base, benefiting livestock nutrition and overall pasture productivity.

In addition to improving forage quality, rotational grazing leads to more even manure distribution, reducing nutrient runoff and enhancing soil fertility. It also supports higher stocking rates than continuous grazing, as pastures remain more productive. While this system requires additional planning, fencing, and water management, the long-term benefits—such as better forage utilization, reduced weed pressure, and improved animal performance—make it a valuable strategy for sustainable livestock production.

Forage Quality Analysis Measurements

When checking if your pasture, hay, or silage makes good feed, three main quality factors stand out: crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF).

For operations where forage makes up most of the livestock’s diet, you'll also want to look at total digestible nutrients (TDN), energy values, and mineral content in your test results.

Understanding Crude Protein (CP)

When you get forages and other feeds tested, crude protein (CP) shows the combined true protein and non-protein nitrogen percentage. This number helps you judge if your forage can satisfy your animals’ protein requirements and guides your feed mixing decisions.

• High-quality legumes typically deliver 20-24% CP
• Fresh grass pastures in spring and summer can reach 20% CP or higher

Understanding Fiber Content: Neutral Detergent Fiber (NDF) & Acid Detergent Fiber (ADF)

Fiber plays a key role in forage quality, directly affecting digestibility and energy value for livestock. The main fiber components—cellulose, hemicellulose, and lignin—determine how easily animals can break down and utilize the forage.

• Lower fiber = Higher digestibility → More energy for livestock and improved intake.
• Higher fiber = Lower digestibility → Harder to chew, less palatable, and reduced nutrient availability.

 

Neutral Detergent Fiber (NDF) – Measures hemicellulose, cellulose, and lignin. It predicts intake potential (lower NDF = higher intake).

• Grasses: High-quality forage has <50% NDF, while poor quality is >60%.
• Legumes: High-quality forage is <40% NDF, while poor quality is >50%.

 

Acid Detergent Fiber (ADF) – Measures cellulose and lignin, indicating digestibility (lower ADF = more digestible).

• High-quality forage typically has <35% ADF.

Grasses tend to have higher NDF and ADF than legumes due to increased lignin content. However, fiber levels vary widely across species and increase in all forages as they mature.

Understanding Moisture and Dry Matter (DM)

Dry matter (DM) refers to the portion of forage excluding moisture, representing the nutrient content available to livestock. Higher DM means greater nutrient density.

• Pastures generally contain 75-90% moisture or 10-25% DM, regardless of forage type. 

Understanding Total Digestible Nutrients (TDN)

Total digestible nutrients (TDN) measure a feed's energy content, combining digestible fiber, protein, carbohydrates, and fats. Higher TDN means more energy is available for livestock. TDN is closely linked to digestible energy and is typically estimated using crude protein (CP) and acid detergent fiber (ADF) values. 

• Low quality: 45 - 52% TDN
• Mid-quality: 52% - 58% TDN
• High-quality: greater than or equal to 58% TDN

Understanding Energy Content

The energy content of forage can be tricky to understand. Forage energy powers essential functions like growth, lactation, and maintenance, but not all energy in feed is usable by livestock. Different metrics help measure energy availability:

• Gross Energy (GE) – Total energy in forage, though not all is digestible.
• Digestible Energy (DE) – Energy absorbed after accounting for losses in feces.
• Metabolizable Energy (ME) – Energy remaining after digestion losses from urine and gas.
• Net Energy (NE) – The actual energy available for maintenance, growth, and production.

In the U.S., digestible energy (DE) is commonly used and reported in Mcal/lb, often estimated using crude protein (CP) and acid detergent fiber (ADF). However, DE has limitations since energy use varies between forages and livestock species, so it should be considered an approximation.

Understanding Mineral Content

A plant’s mineral content reflects soil conditions and fertilizer use. In forage analysis, total minerals are reported as “ash,” with macronutrients listed in percentages (%) and trace minerals in parts per million (ppm).

All minerals are essential for livestock health, but proper balance is key:

• Calcium to phosphorus – Maintain a 2:1 ratio for optimal nutrition.
• Zinc to copper – Keep a 4:1 balance, favoring zinc.
• Iron – Should stay below 500 ppm, as excess iron can block nutrient absorption and may contribute to insulin resistance. Legumes typically contain more iron than grasses.

Physical Assessment of Hays

Visual inspection is as crucial as chemical analysis when selecting hay. Assess color, smell, maturity, leafiness, and foreign matter content.

Hay Color

Color provides initial insight into hay quality. Ideally, hay should appear green, indicating good nutrition, though this shouldn't be your only criterion, as weeds also retain greenness when dried.

• A pale yellow exterior suggests sun-bleaching, which is acceptable if limited to half an inch or less. These bleached areas contain less carotene and palatability but minimally impact overall nutrition.
• Completely yellow hay often indicates over-maturity at harvest, resulting in reduced nutritional value and palatability. 
• Dark brown or black coloration typically signals moisture during harvesting and baling, allowing microbial growth that generates heat and causes darkening. This hay may emit a sweet, caramel-like odor. Heat-damaged hay potentially contains harmful mycotoxins and offers diminished nutrition, digestibility, and palatability.

Note that red clover naturally browns during drying without indicating quality issues, highlighting the importance of identifying forage species during evaluation.

Smell

Quality hay emits a clean, fresh, slightly sweet fragrance. Avoid hay with musty or stale odors, indicating potential mold contamination.

Dust Levels

Examine hay for excessive dust. Bales that release dust clouds during handling can trigger or worsen respiratory conditions in your livestock.

Leafiness

Check the leafiness of the hay inside the bale. Leaves hold more nutrients, protein, and digestible carbohydrates than stems, so high-quality forage should have plenty of leaves with minimal stems and seedheads.

Examine Seedheads, Flowers, and Stem Thickness

Examine grass hay for seedhead quantity and size and legume hay for flower numbers. Fewer, smaller seedheads and fewer flowers indicate less mature, more nutritious hay.

As plants mature, their nutritional value decreases while lignin content increases, reducing digestibility. Harvest maturity significantly impacts nutrition, far more than cutting numbers.

Stem thickness is a key indicator of forage maturity at harvest. Thick, coarse stems suggest the hay was cut at a later growth stage, while finer stems indicate an earlier harvest. However, if fine stems lack leaves, the hay may have been cut too soon, resulting in immature forage.

Presence of Foreign Matter

Finally, check for foreign matter that’s unsafe or inedible, like insects, trash that may cause gut issues, or dead animals that could introduce botulism toxins.

Comparing Fresh Forage Quality Versus Hay

Fresh forages and hay contain notable nutritional differences. These variations primarily stem from the significantly higher water content in fresh pasture grasses and legumes, directly impacting all other dietary components. 

Moisture Content

• Pasture plants: 75 - 90% moisture 
• Hay: 10 - 12% moisture

Hay's lower moisture allows for more extended storage periods without mold growth. However, you must increase your livestock’s water intake when feeding hay. 

Crude Protein (CP)

• Grass pastures: 10 - 20% 
• Legume pastures: 20 - 24% 
• Grass hays: 6 - 10%
• Legume hays: 12 - 20%

Fresh forages typically have higher crude protein levels than hay. Once forages are harvested, their proteins start breaking down into nitrogen-based compounds like ammonia and urea, altering the hay’s CP percentage and amino acid profile.

The CP of all pasture forages also declines as the season progresses and plants mature. 

Fiber and Forage Digestibility

• Young pasture forages have better digestibility than mature ones
• Fresh pasture is more digestible than hay cut at the same growth stage 

Forage digestibility decreases as fiber content increases. This inverse relationship becomes more pronounced as plants mature, with rising levels of lignin, cellulose, and hemicellulose, making these forages progressively more difficult for animals to digest.

Vitamin Levels

• Pasture forages have more vitamins A, C, and E than hay

After harvest, forage experiences nutrient degradation due to oxygen and sunlight exposure. This vitamin breakdown process continues throughout hay storage, resulting in substantially lower vitamin content than fresh forages.