Get reliable rangeland science

Written by Rachel Frost and Jeff Mosley, Montana State University

The nutrient value of rangeland forages depends upon their ability to meet the grazing animal's nutritional requirements throughout the year. Livestock (or any animal) are a production unit, and each unit has different nutrient requirements based upon its physiological status (yearling steer, cow-calf pair, pregnant cow, dry cow, etc.). Plant nutritional values should be compared with the corresponding animal requirements for the animal's physiological status. The nutrient evaluation of rangeland forage is based upon the plant's content of protein, phosphorus, energy, and carotene (vitamin A). These four principal nutrients are those mostly likely to be deficient in rangeland forage, although localized deficiencies of other nutrients or minerals are possible.

Protein is calculated from the amount of nitrogen contained in plants. Grasses decline in digestible protein rapidly as they mature. Nitrogen is moved by the grass plant from aboveground parts available to the grazing animal to storage organs below the ground as the current year's grass growth matures. Shrubs, on the other hand, are good sources of protein even after they reach full maturity because nutrients remain in branches and leaves as well as below ground. Forbs, in general, are intermediate between shrubs and grasses with respect to protein content during most seasons.

Phosphorus, a macro-mineral, is often limiting in range forage plants. Grasses are low in phosphorus soon after they form seed. Shrubs are generally considered good sources of phosphorus for general animal maintenance and gestation, even when mature. Most forbs have a phosphorus content only slightly lower than that of shrubs. Phosphorus content of plants can fluctuate depending on the soil status. Soils high in phosphorus will allow plants to contain more phosphorus than where soils are limiting in phosphorus content.

Energy values of forage are commonly reported as total digestible nutrients (TDN) or digestible energy (DE). Grasses are generally considered good sources of energy primarily because of their high content of cellulose. In very mature grasses however, digestibility will be so low as to reduce intake and thereby reduce total energy intake. Digestibility is the proportion of a dietary nutrient available for animal metabolism and indirectly tells us something about intake (as digestibility goes down, intake may go down). Shrubs are not considered good sources of energy after they reach fruit development. Again, forbs are intermediate between grasses and shrubs in furnishing energy.

The single biggest problem however, especially when forage plants are mature, is maintaining intake so that the animal gets enough total nutrients each day.  Other factors may also affect the nutritive value of range plants. Range condition, for example, may alter total forage intake of grazing cattle. Research shows that protein and phosphorus are about the same in plants growing on good- versus poor-condition range. However, plant species on poor-condition range may be less digestible than plant species on good-condition range, which can reduce total forage intake by grazing animals. The animals either can’t or won’t eat enough. An appropriate mix of grasses, shrubs, and forbs, is necessary to provide nutritious forage to livestock on a yearlong basis.

Classification of Range Forage Value: To facilitate management, range plants are commonly classified according to their forage value.

• High forage value designates plants that are nutritious, palatable, and produce abundant forage.
• Medium forage value denotes a plant that will provide adequate nutrients if eaten; however, it is not preferred by animals or does not produce abundant forage.
• Low or poor forage value describes plants that simply do not provide adequate nutrients to the grazing animal. Additionally, most plants containing anti-quality compounds that reduce intake or poisonous plants containing toxins that cause illness or death in herbivores are classified as having "low" forage value.

Ways to Manage Your Forage Value Management factors such as stocking rate and specialized grazing systems can also influence grazing animal nutrition. Heavy stocking reduces individual animal performance and can result in damage to the forage resource. Although the influence of animal numbers can be altered by controlling the time the plants are exposed to grazing and allowing for adequate recovery periods, proper stocking rates are essential to long-term rangeland health and healthy, productive grazing animals. Grazing systems may reduce or improve forage nutritive value. Although forage reserves are a necessary part of ranch planning, and some amount of plant material should be left for resource protection, animal production may suffer if pastures are allowed to accumulate too much old plant growth. This can be offset by adjustments in stocking rates or changes in range condition. Carefully planned grazing can help increase diet quality. In grazing cells, for example, the longer animals stay in a particular paddock, the further diet quality is reduced.

Adapted from: Ruyle, G. 1993. Nutritional Value of Range Forage for Livestock. Arizona Rancher's Management Guide.

In this section you'll find addtional information regarding:

• Seasonal Changes in Forage Quality and Quantity
• Supplemental Feeding of Livestock on Rangelands

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Seasonal Changes in Forage Quality and Quantity

Written by Rachel Frost and Jeff Mosley, Montana State University

Forage quality and quantity are both important to maintaining livestock and wildlife production. Quality and quantity both change substantially throughout the year, and it is important to understand how to balance these attributes. Supplementation programs should be designed to specifically address a deficiency in quality or a lack of quantity to be effective.

Forage Quantity Forage quantity can be limiting even when there appears to be plenty of available standing crop. This occurs because herbivores have very definite forage preferences and dietary requirements. For forage quantity to be adequate, there has to be sufficient quantity of the preferred plant species for the specific herbivore and sufficient forage of acceptable quality. For example, forage quantity can be a problem in the spring when the quality of the forage is high, but the availability of the green plant material is limited. Drought conditions and overgrazing are the most common causes of insufficient forage quantity.

Forage Quality Forage quality can be affected by a variety of biological and environmental factors. In general, the nutritional value of forages is highest when the plant has an abundance of young, actively growing leaves and declines as the plant nears maturity. Understanding how and why forage quality changes throughout the year can help producers match the nutritional requirements of their livestock — or wildlife managers matching vegetation to the wildlife species — to the nutrient content of the forage resource. This permits producers to target forage supplementation to the specific needs of their livestock, which should reduce supplementation costs.

See the fact sheet "Why Forage Quality Changes" for a more detailed discussion on all factors.

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Supplemental Feeding of Livestock on Rangelands

Written by Rachel Frost and Jeff Mosley, Montana State University

Under certain conditions, livestock grazing western rangelands are not able to consume enough nutrients from forage alone to meet their nutritional requirements. At these times, supplementary nutrients are often provided to maintain production levels. Supplementation is one of the biggest expenses of range livestock production, accounting for up to 70% of the operation's total variable expenses. Providing the proper supplements in the correct amount and at the appropriate time can save producers money and conserve forage resources.

Determining the proper supplementation program requires livestock managers to know the following:

• nutritional requirements of the grazing animal
• nutrient content of the forage
• cost of supplementation and expected benefits 

The decision to provide a supplement should be based on forage supply, protein content, and animal body condition.

Basic Ruminant Nutrition. Ruminants differ from pigs and humans in their ability to digest fibrous plants because they have a rumen that allows for fermentation before the food enters the abomasum (stomach) of the animal. The rumen houses microorganisms that are capable of breaking down cellulose through fermentation. These microorganisms break down consumed feedstuffs for their own nutritional requirements and in return release volatile fatty acids that are a major energy source for ruminants. The microorganisms eventually die, and their bodies pass into the small intestine, where they are digested and contribute to the protein supply of the animal. This symbiotic relationship, while essential, also adds to the complexity of predicting and effectively meeting the nutrient requirements of ruminant animals.

Relationship of Protein and Energy within the Ruminant. Ruminants need the microorganisms to "unlock" the energy in forage, allowing them to harvest and make use of cellulose that is unavailable to non-ruminants. The existence and growth of microorganisms depends on an adequate supply of nitrogen, primarily found in protein. Supplementing ruminants with protein increases the number and activity of microorganisms in the rumen, which improves forage digestion and increases passage rate and intake of forages. Increasing forage intake improves energy availability; therefore, correcting a protein deficiency is generally the first supplementation priority.

Types of Protein Supplements. Escape protein does just what its name implies and escapes digestion in the rumen. It travels to the small intestine where it is broken down and used directly by the animal. Escape protein can be important to the ruminant because any rumen degradable protein that is not consumed by the microbes can be lost through the urine. However, when animals are consuming low-protein forages, as is often the case on rangeland, then a supplemental protein source is required to stimulate rumen microbial activity and encourage forage intake. For cattle consuming low protein forage, 60 to 70% of the supplemental protein should be ruminally degradable.

Written by Rachel Frost and Jeff Mosley, Montana State University

When properly implemented, a grazing system can help rangeland and livestock managers achieve management objectives related to rangeland and livestock production and ecosystem structure and function. Selection of the proper grazing system depends upon understanding the unique combination of topography, soils, vegetation types, and climate that overlap the management unit. No grazing system is better than any other, but each system is appropriate for specific conditions.

A grazing system is a particular way of managing the interactions between plants, soils, and grazing animals. If you graze animals, you already have a grazing system of some kind. As you begin to design or redesign your grazing system, remember that any grazing management problem usually has many possible solutions, and very few things you can do are "right" or "wrong." Most of all, remember than no one grazing system is "best."

By addressing a few simple principles, most grazing management problems can be solved. The successful grazing plan creatively combines these principles specifically for your operation's unique circumstances. Your grazing system will be your particular way of managing your plants, soils, and grazing animals.

A variety of grazing systems have been used on rangelands in the western United States and Canada. Follow the links below to learn more about each system:

• Rest-Rotation Grazing
• Deferred-Rotation Grazing
• Seasonal Suitability
• Best Pasture
• Short Duration Grazing
• Continuous Grazing

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Rest-Rotation Grazing The rest-rotation grazing system was designed by Gus Hormay of the U.S. Forest Service and was first implemented in the 1950s and 1960s. Under rest rotation, one or two pastures are rested the entire year while the remaining pastures are grazed seasonally, depending on the number of pastures and herds. For example, one pasture in a three-year, three-pasture rest rotation might be managed as follows during a three-year cycle: 1) graze the entire year or growing season; 2) defer until desirable forage plants set seed, then graze; and 3) rest. This schedule rests about one-third of the range annually.

• Advantages: Rest provides an opportunity for vegetation and soils to recover and helps meet multiple use objectives such as providing hiding cover for birds and forage for other wildlife and leaving ungrazed areas for public viewing and enjoyment. Rested pastures provide forage for emergency use during drought and provide opportunities to implement relatively long-term rangeland improvement practices — for example, burning, reseeding, brush control — during scheduled rest periods.

• Disadvantages: Elk or other wild herbivores may graze rested pastures, negating some of the benefit of rest or deferment from livestock grazing. The increased stock density in grazed pastures can reduce dietary selectivity of livestock and decrease their overall diet quality.

The benefits of a full year of rest can quickly be nullified if previously rested pastures are overgrazed, particularly in arid regions where frequent drought conditions can impede rangeland recovery.

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Deferred-Rotation Grazing The key feature of deferred-rotation grazing is that each pasture periodically receives deferment until seed set. Systems can vary in the number of pastures and the length of time between deferments (usually 2 to 4 years).

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Seasonal Suitability. Seasonal suitability grazing systems attempt to partition and manage diverse vegetation types that differ due to elevation, ecological site, ecological condition, or precipitation, and to move animals based on seasonal forage production. This system allows managers to strategically move grazing animals to take advantage of forage when it is abundant and of high quality. For example, in southwestern deserts, seasonal suitability systems use creosote bush and mesquite shrublands during winter and early spring, while tobosa grass and alkali sacaton ranges are used during summer. In other areas, livestock may be rotated through native range in the summer, crested wheatgrass in the spring, and Russian wildrye pastures in the fall. Seasonal suitability also has been used on mountain ranges in the northwestern United States where grassland, forest, and meadow vegetation types provide late spring/early summer use, late summer/early fall use, and fall grazing, respectively. Seasonal suitability has been practiced where desert (winter use), foothill (spring use), and mountain ranges (summer use) are managed as separate, seasonal grazing units.

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The Best Pasture System The best pasture system attempts to match animal movements with irregular patterns of precipitation and associated forage production. Precipitation patterns may be spotty and unpredictable. Therefore, areas separated by only a few miles may differ greatly in forage production. The best pasture grazing system has no set rotation schedule; rather, it requires that land managers exercise flexibility. For example, when a local rain event causes a flush of annual forbs in a particular pasture, grazing animals are moved to that pasture until desired utilization levels of the ephemeral forbs have been achieved.

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Short Duration Grazing

 

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Continuous grazing is defined as grazing a particular pasture or area the entire year, including the dormant season, while season-long grazing refers to grazing a particular pasture or area for an entire growing season. Stocking rate is key to the success of a continuous or season-long grazing plan. Stocking at light rates during the growing season is particularly important in continuous grazing systems to ensure adequate forage is left to carry animals through the dormant season. Light stocking rates enable animals to be highly selective in the plants they consume, resulting in a higher quality diet. Furthermore, livestock are not subjected to the stress of frequent moving to new pastures, which can decrease production. Continuous or season-long grazing works best on flat areas with well developed water systems — that is, watering points no more than two miles apart — and where most of the plants have some value to grazing animals.

Adapted from: Howery, L.D., J.E. Sprinkle, and J.E. Bowns. 2001. A Summary of Livestock grazing systems used on rangelands in the western United States and Canada. Arizona Ranchers' Management Guide.

Written by Rachel Frost and Jeff Mosley, MSU

Think about the wide variety in foodstuffs consumed by people around the world. What people in one region consider a delicacy, people in another region would consider inedible. Even though all people are the same species! Now, think about the many species of herbivores that graze rangelands. Each species (and often individual animals) has very different dietary habits and preferences that are molded from their environment, their genetics, and their social interactions. In general, animals consume foods that they are physiologically adapted to digest and that meet their nutritional requirements. These inherent dietary differences result in herbivores being classified into three major groups: grazers, browsers, and intermediate feeders. In addition, physiology alone does not dictate diet selection in animals. The diets of animals are strongly influenced by 1) social interactions with mother, peers, and people; 2) feedback from nutrients and toxins in plants; and 3) interactions with their physical environment including location of water and predators.

• Factors that Affect Diet Selection
• The Role of Learning in Diet Selection
• Nutritional Requirements of Livestock

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Factors that Affect Diet Selection

The physical characteristics of animals can have a profound influence on their diet selection. These main characteristics should be considered when designing a grazing plan and calculating stocking rate.

Type of livestock: Graze the type of livestock best suited for the kind of forage available and the forage's nutritional quality. The amount and kinds of forages that livestock consume depend upon a variety of factors, including species, breed, physiological status, and experiences early in life. Understanding why livestock eat certain plants or parts of plants allows managers to use diet selection as a management tool to direct the vegetation change in plant communities toward management objectives.

Grazers. Grazers, including cattle and horses, primarily eat grasses. The sheer size of the mouth of these herbivores limits their ability to select individual parts (leaves, twigs) of plants. The large rumen of cattle and the active cecum of horses are well suited to consuming large quantities of low-quality, fibrous forage like dormant grasses. They obtain the nutrients they need by consuming a large quantity of low-quality forage.

Browsers. Browsers focus their foraging on leaves, flowers, and twigs of woody species. They typically have a smaller, more pointed mouth than grazers. The narrow muzzle and other dental adaptations of browsers help them select individual plant parts of higher nutritional quality. In general, the diet of browsing animals is higher in protein and more digestible than the diet of grazers. Many browse plants, however, contain secondary compounds or toxins that limit their intake. Browsers have developed several physiological characteristics that help them either metabolize or avoid exposure to these compounds. For example, many species of browsing herbivores have a large liver in relation to their body size, which aids in metabolism of harmful plant toxins. Some browsers are equipped with salivary glands that bind tannins, an anti-quality compound found in some browse plants.

Intermediate Feeders. Intermediate feeders have adaptations of both grazers and browsers. They typically possess a narrow muzzle and a large rumen relative to body mass, which allows them to graze selectively and still tolerate substantial fiber in their diet. Sheep are intermediate feeders that possess a relatively small mouth allowing them to graze relatively close to the ground and to strip leaves or flowers from stems. The diet of intermediate feeders generally is dominated by forbs, although they will readily consume grasses when grass plants are succulent or when other forage has limited availability.

Breed: Breeds of livestock differ in size and production characteristics, which dictate their nutrient requirements, dry matter intake, and digestive ability. These factors influence which plants, and in what proportion, an animal chooses to include in its diet. Livestock selection and breeding may also affect the kind of terrain where animals can effectively forage. Breeds of cattle developed in mountainous terrain may graze rugged rangeland more uniformly than breeds developed in gentler terrain.

Age: Animal age can also profoundly affect diet selection and tolerance to secondary compounds. Metabolic requirements decline with age, so older animals need less food and spend less time foraging. Compared with adults, young, growing animals need diets higher in protein and energy and lower in fiber. Their search for a more nutritious diet takes more energy. This, combined with limited foraging knowledge, may lead younger animals to try novel foods and retry foods that once made them sick. Animals just weaned are expanding their diet selection, so they are also more willing to try novel foods.

As herbivores age, their incisor teeth wear, so they are less able to graze and achieve maintenance requirements, particularly on short forage. Wear on incisors also influences forage selection.

Body Condition: How fat or thin an animal is influences its foraging behavior. Animals in low body condition or on a diet that fails to meet their maintenance requirements may have reduced tolerance for plant toxins. That’s because there is a nutritional “cost” to metabolize a toxic or aversive plant compound. Detoxification most often occurs in the liver, so an animal that consumes chemically defended plants needs a large, healthy liver. Prolonged nutritional stress can reduce liver mass. Protein and mineral supplements can enhance rumen microbial function, liver enzymes, and other compounds for negating toxins, all of which enhance an animal’s detoxification abilities.

Malnourished and thin herbivores generally eat more than animals in good condition. When forage is limited, animals in low body condition may turn to poisonous or less desirable plants to maintain that higher intake.

Gender: Males and females select different diets, in part because of differences in size and overall nutrient requirements during reproduction. Morphological and physiological traits, such as growth rate and feed conversion efficiency, also contribute to differences in diets. Males generally have larger stature and muzzle size than females and may have greater energy needs. Males and females of most species of wild herbivores segregate when it is not breeding season. Therefore, they use different portions of the land area and consume different forages.

Stage in Production Cycle: Animals choose their diets based on nutritional needs, which change dramatically during life stages. The greatest nutrient demands are for lactating females who need more energy and protein to support milk production. However, care should be taken to prevent consumption of certain plants that are particularly harmful to females during gestation, such as ponderosa pine, lupine, and veratrum. Consumption of these plants can cause serious birth defects or even death of the fetus.

Individual Variation and Heritability: “Individuality” is a powerful force that influences dietary preference. Even animals of the same age, sex, breed, and experience will vary in their plant preferences. Some prefer plants high in energy, while others prefer those with medium or low energy concentrations. Just as with humans, animals have unique dental structure, physical abilities, organ size and function, and sensory abilities. Individual differences affect foraging abilities and how an animal metabolizes nutrients. Individuals also vary in responses to plant toxins. Almost every feeding trial with toxic plants has revealed individuals capable of consuming what would be a lethal dose to other animals without showing signs of toxicity.

Grazing selectivity: Grazing animals consume the plant species and plant parts that provide the least disruption to their digestive system and best meet their seasonal nutritional needs. Most plants contain natural chemicals that inhibit digestion when they are consumed above some level. Grazing animals are always trying to optimize nutrient and energy intake and minimize the consumption of chemicals that adversely affect digestion and extraction of nutrients from the forage; hence, the need to selectively consume forage species and plant parts. The performance of individual animals will be best when they are allowed to be picky eaters. However, repeated selective grazing of the same plants typically harms the preferred forage plants. Grazing systems are management tools that attempt to minimize an animal's ability to repeatedly and selectively graze desired plants, while trying to optimize animal performance and plant selection across all forage species.

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Role of Learning in Diet Selection

Herbivores forage in a complex environment. How do they learn which foods are nutritious and which foods are toxic or low in quality? Herbivores begin learning about what foods are safe before they are even born and continue the process throughout their life enabling them to survive in a world where toxin and nutrient levels of forages are constantly changing. These same processes allow them to make foraging decisions when they are moved to new pastures with unfamiliar foods.

Mom as a Role Model. A young animal first learns about which foods to eat and which to avoid by foraging with its mother. By the time the animal has to forage on its own, it is already familiar with a number of plants that are nutritious and safe to eat. Thus, an animal divides its foraging world into two food groups, familiar and novel. Animals learn through trial and error about novel foods based on the postingestive consequences of the novel foods they eat.

Novelty. Like most people, herbivores sample novel foods cautiously. If the consequences of eating the food are positive--feedback from needed nutrients---the animal will increase intake of the new food. If the consequences are negative --illness from toxins or lack of feedback because the food is low in nutrients--the animal will decrease intake of the food. When eating a meal of several foods, novelty is the key to figuring out which foods are harmful and which are nutritious. When animals eat a meal of several familiar foods and a novel food and then experience illness, they subsequently avoid the novel food. Conversely, when animals suffering from a nutritional deficiency recover after eating a meal of several familiar foods and a novel food, they learn to prefer the nutritious novel food. Herbivores also reduce intake of familiar foods when the flavor of the food changes. Changes in flavor may occur when forages grow on different sites or as plants mature. If the change in flavor results in illness, the animal avoids the food in the future. If, however, the change in flavor results in positive consequences then the animal will continue to eat the food.

Prior illness. Herbivores continuously sample foods, even foods that made them ill. If an animal gets sick after eating a meal of several familiar safe foods and food that caused illness in the past, subsequently it will avoid the food that caused illness. Animals are able to remember which foods previously made them sick for a long time.

Generalization. Animals use past experiences with familiar foods to make foraging decisions about new foods. If new foods have flavors similar to foods that made the animal ill in the past, it is less likely to eat those foods. Conversely, if new foods have flavors similar to familiar nutritious foods, animals ingest those foods more readily.

Amount and timing. If the foods an animal eats during a meal are equally unfamiliar and the animal experiences illness, how does the body determine which food to avoid? Animals pair feedback--positive or negative--with the food they ate in the greatest amount, provided both foods are equally new. Animals also form aversions to or preferences for foods when food ingestion is quickly followed by either illness or positive postingestive signals, provided the foods are equally familiar to the animal.

Salience. At one time researchers thought animals formed aversions to certain strong flavors more readily than others. They referred to these flavors as salient. Bitter, for example, was thought to be a salient flavor because many toxic compounds are bitter. Further study indicated that the response the scientists observed was simply due to novelty. When animals are reared on bland foods and get sick after eating a meal of several foods, one of which has a strong novel flavor, they form an aversion to the food with the strongest flavor. If, however, they are reared on foods with strong flavors and get sick after eating a meal of foods with strong familiar flavors and a novel bland food, they form an aversion to the bland food. Thus animals associate illness with novelty not necessarily with strong flavors.

Conclusion. Animals depend on the availability of familiar foods to make correct foraging decisions. When animals are moved to new foraging locations that contain only novel foods, it is more difficult for them to select safe nutritious foods and to avoid toxic foods. Understanding how animals discern safe from harmful foods is important information managers can use to help animals make transitions to new locations or train animals to eat new foods.

Adapted from: BEHAVE. Learning What to Eat and What to Avoid. Behavioral Principles and Practices - No. 1.1.3

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Nutritional Requirements of Livestock

The essential nutrients required by grazing animals are water, energy, protein, minerals, and vitamins. These nutrients are needed to maintain body weight, growth, reproduction, lactation, and health.

Water. Water is essential for all livestock, and producers should plan for an adequate supply of clean water when designing any type of livestock enterprise. Dirty, stagnant water can lead to inadequate water consumption, which will reduce feed and forage intake and compromise livestock performance. The amount of water required depends on the physiological stage of the animal and the climate. Lactating animals require more water, and the amount of water required increases as atmospheric temperature increases. For example, at temperatures above 35°C (95°F), cattle require about 8 to 15 liters (2.1 to 4 gallons) of water per kg (2.2 lb) of dry matter intake. Generally, cattle require ~2.6% of their body weight in dry matter (DM) intake per day. Therefore, a 1000 lb cow could require as much as 175 liters or 45 gallons of water a day! Daily water consumption of ewes will vary from 0.75 to 1.5 gallons depending on climate and stage of gestation. Water availability should be closely monitored because a deficiency in water will result in death much faster than a deficiency of any other nutrient. Add can cows eat snow

Protein. In most situations, the amount of protein supplied in the diet is more critical than the quality of the protein. Ruminants have the ability to convert low-quality protein sources to high-quality proteins through bacterial action. Microbial protein synthesis is sufficient to supply the protein needs as long as adequate precursors are supplied, except during lactation for high milk producing animals. Protein is required by all grazing animals for tissue growth and repair. Protein required for a 1000 lb nonlactating cow is around 1.6 lb/day or 7% crude protein in the diet. When the cow is lactating, 2.0 lb or 9.6% dietary crude protein is required. If protein is deficient in the diet, grazing animals must break down body tissue to obtain sufficient protein. A protein-deficient animal must break down 6.7 lb of lean body tissue to supply 1 lb of protein, resulting in severe weight loss.

Energy. Insufficient energy probably limits performance of livestock more than any other nutritional deficiency. Energy requirements vary greatly with stage of production, and adequate amounts of energy are extremely important during late gestation and early lactation. Energy deficiencies can cause reduced growth rate, loss of weight, reduced fertility, lowered milk production, and reduced wool quantity and quality. Energy is obtained from carbohydrates in the plant material and can be stored in the form of body lipids. However, heavy demands against fat stores as an energy source to meet daily needs may delay estrus and reduce conception in breeding females. Live weight gain can only occur after the animal’s energy requirements for maintenance and lactation are met.

Vitamins and Minerals. Ruminants require all the fat-soluble vitamins (A, D, E, and K), but they can synthesize the B vitamins in their rumen. Normally, the forage and feed supply contain all essential vitamins in adequate amounts, except vitamin A which is obtained as carotene from green plants and is often deficient in dormant forage. However, vitamin A can be stored in the liver in amounts sufficient to last considerable periods of time, such as winter dormancy or prolonged drought. Salt is essential for many body functions and important to maintain intake of feeds and water. Calcium and phosphorus are needed to maintain growth, feed consumption, normal bone development, and reproductive efficiency. Other nutrients and minerals such as vitamin E and selenium are important for maintenance of healthy bodies and reproduction.

Factors that Affect Nutrient Requirements. The nutrient requirements of domestic livestock have been provided in detail by various National Research Council (NRC) publications. However, these NRC requirements have been developed on pen-fed livestock where maintenance requirements are easily calculated and tend to vary only slightly within a given weight, sex, age, and physiological state.

• Physiological stage. The greatest influence on nutritional requirements of livestock is their life stage in production. The key physiological stages in the life of grazing animals are growth (i.e., young animals), late pregnancy, lactation, and maintenance, generally during non-lactating periods. In general, the highest nutritional requirements are for lactation, followed by late gestation, growth, and finally maintenance. Managing livestock production schedules to match nutritional demands with forage quality and availability can greatly improve the efficiency of a production system.

• Topography. The nutrient requirements of grazing animals are also dependent on environmental and climatic variables. Grazing and voluntary travel also require substantial increases in energy expenditure. Range animals walk long distances, climb gradients, and ingest herbage often of low dry matter content, thus spending more time eating and foraging for food. Research estimates that cows grazing rangeland use 30% more energy than confined cows because of longer grazing time and longer travel distance.

• Climate. Climate, particularly temperature, also affects the amount of feed an animal needs to maintain its body functions. As ambient temperature drops, an animal’s metabolic rate increases, and more energy is needed to maintain internal heat. This effect can be exacerbated by wind or wet hide/hair on the animals.

 

Rangeland cattle producers strive to graze their livestock in ways that are economically, socially, and environmentally sustainable. A major challenge facing many producers is to better manage cattle grazing in concert with clean water, fish and wildlife habitat, and recreational activities in riparian zones — for example, stream sides and shorelines. Attainment of these goals rests largely in a producer's ability to cost effectively control when and where cattle graze.

Opportunities exist for applying animal behavior principles to control cattle distribution and limit cattle grazing impacts in riparian areas. Adjusting the timing of grazing, supplemental feeding, herding, and selective culling are four strategies that producers can use to help ensure the sustainability of riparian cattle grazing. All four practices are more effective when ranchers capitalize on their knowledge of cattle grazing behavior.

Understanding and manipulating cattle behavior provides numerous opportunities for ranchers and scientists to develop cost-effective ways to limit grazing impacts in riparian zones. Failure to seize these opportunities will inhibit the economic, social, and environmental sustainability of riparian cattle grazing.

• Timing of Grazing
• Supplemental Feed

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Timing of Grazing

The timing of riparian grazing is important for good management.  Cattle typically avoid grazing on wet soils.  This explains why cattle usually spend more time feeding in upland sites during spring and early summer, and wait to graze riparian zones in mid and late summer.  Therefore, allowing cattle to graze early in the season may limit utilization of streamside plants and streambank trampling if the ground surface is sufficiently wet.

Cattle browsing of riparian shrubs can be avoided by closely monitoring the abundance and palatability of the herbaceous forage.  Cattle browsing of riparian shrubs increases with decreased palatability and availability of herbaceous vegetation. As long as the herbaceous component in the riparian zone is succulent and plentiful, cattle will not utilize shrubs much, even late in the growing season. Cattle, however, tend to shift their diet selection to riparian shrubs if the herbaceous component has been largely consumed or has reached seasonal maturity. Accordingly cattle consume more riparian browse in a dry year than in a wetter year.  Some evidence indicates that increased browsing of willows in late summer may be related to a change in the chemical makeup of willows.  For example, increased cattle browsing of planeleaf willow (Salix planifolia) coincides with decreased concentrations of ampelopsin in its foliage. Ampelopsin is a flavonoid, a specific plant metabolite that is believed to be unpalatable to browsing animals.

In mountain meadows, shrub utilization by livestock is usually slight as long as a herbaceous stubble height of 10 cm (4 inches) or greater remains.  A definite shift in preference typically occurs when the herbaceous vegetation is utilized beyond this level. The shift is increasingly apparent when stubble height is reduced below 5 cm ( 2 inches).  Cattle use should be closely monitored when stubble height for the most palatable herbaceous species reaches 7-8 cm (3 inches). At stubble heights below 7 cm (3 inches) cattle browsing of shrubs can quickly become excessive.  Cattle behavior sometimes becomes visibly more unsettled when their diets shift from herbs to browse, and astute observers can use this behavioral cue to indicate when cattle may need to be relocated.

Cattle may disperse out of a riparian zone before the herbaceous stubble height is reduced below 10 cm (4 inches). Cattle often leave valley and canyon bottoms late in the season when cold air accumulates in the riparian zone, and when late-summer or early-fall rains improve the palatability of the herbaceous forage on adjacent slopes. Thus, late-summer or early fall may be an opportune time to allow cattle access to some riparian areas.  However, cold-air drainage in flat, broad valleys is not prohibitive to cattle, and late in the season cattle are often drawn to these riparian areas because they contain the only remaining succulent vegetation.  Understanding site-specific animal behavior is critically important for developing riparian grazing plans.

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Supplemental Feed

Supplemental feed can help disperse cattle away from riparian zones. Cattle tend to disperse farther from supplemental feeding sites when hand-fed supplement is not provided every day. Protein can readily be fed at two- or three-day intervals, even weekly, which can reduce feeding costs significantly. Grain supplements for energy, however, must be fed daily to avoid reducing fiber digestion. Hand-fed supplement should be provided when it least disrupts normal grazing activity patterns. Early afternoon is generally best. Animals supplemented in the morning expend more energy foraging and traveling compared with animals supplemented in the afternoon or un-supplemented animals.

Self-fed supplements should be placed no more than two miles apart if in level or gently rolling topography; supplements are usually placed one mile apart or closer if the topography is rough. Supplements should not be located less than one-third to one-fifth miles from surface water to limit animal impacts in riparian areas. However, it is important to remember that animals consuming supplements with high salt content need access to an ample supply of water so that animals are able to excrete the salt via urine. Livestock consuming salt-mix supplements often increase their water intake 50 to 75%. Salt-mix supplements will not effectively change animal distribution when there are many natural salt licks or alkali spots in the area.

Cattle tend to consume supplemental salt only when it is convenient during their normal foraging pattern, but they are not apt to appreciably alter their behavior to obtain salt. Consequently, salt placement is generally incapable of overriding the attraction of water, shade, and palatable forage often found in riparian zones.

Supplements should be placed in accessible sites. Moving the locations from year to year can help limit impacts to soils and vegetation from congregated animals, but moving the locations annually may prevent cattle from learning where to locate the supplement. Unfortunately, permanent locations for supplementing discourage animals from foraging far away from the feeding site and may encourage substitution feeding. Inclement weather may reduce supplement consumption from self-feeders because animals avoid traveling to the feeders. Consumption during inclement weather is more easily maintained when supplement is provided near shelter cover.

Movements between pastures are made easier by withholding supplement just prior to turning cattle onto a new grazing area. Upon entering the new area, the cattle are then trailed to the new supplementation site(s) and greeted with a familiar reward. Gathering animals very early in the morning, prior to their morning grazing bout, and then herding them to new supplementation sites works well. Supplemented animals are easier to handle and easier to gather and herd than un-supplemented animals.

Written by Rachel Frost and Jeff Mosley, Montana State University

One important goal of grazing management is to prevent large numbers of animals from congregating in any one location for too long. Thus, grazing distribution is a major concern for livestock and land managers. This is especially important on sensitive areas such as streams and riparian areas. When grazing animals cause damage to soils or plants, it is often caused by poor animal distribution, not too many animals for the management unit. Animals clearly prefer some grazing sites over others, increasing the grazing pressure on used areas and leaving other areas underutilized. Spatial and temporal distribution of livestock is partly a function of rangeland resources, heterogeneity of vegetation types, forage abundance, and watering points. Water development, supplementary feed placement, and fencing are several tools that can help improve livestock distribution.

• Factors that Affect Livestock Grazing Distribution
• Managing Livestock Distribution
• Herding
• Selective Culling

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Factors That Affect Livestock Grazing Distribution

Animal behavior — Animals make conscious decisions about where to graze based on their perceptions of an area, their knowledge of plants consumed in the past, and their memory of potential choices.

Distance to water — Access to water is critical for grazing animals; therefore, the location and number of watering points are the main factors in determining movement, distribution, and concentration of grazing animals.

Topography — Hilly, mountainous, or rocky terrain can be difficult for grazing animals to traverse. The effect of topography varies with the kind of grazing animal.

Vegetation type — The distribution of grazing animals is strongly influenced by their forage preferences. Neighboring plant communities may receive different grazing pressure because they contain different kinds of plants or the plants differ in palatability.

Weather — Grazing animals must regulate body temperature and therefore seek out areas that provide thermal regulation such as shade or windbreaks.

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Managing Livestock Distribution

Each management unit has its own unique set of distribution problems; however, several tools and strategies can be employed to draw animals away from preferred areas and into underutilized areas.

Water — Often the most effective way to improve the uniformity of grazing is to increase the number and/or change the location of watering points. Animals should not have to travel more than a quarter to a half mile from forage to water in steep, rough terrain or more than one mile on level or gently rolling ground. Animals will overuse sites near water locations rather than walk greater distances to abundant forage; therefore, the development of additional water sources can improve animal performance by making additional forage available.

Kind of livestock — The species and class of livestock grazed should be matched to the vegetation and the topography. Cattle prefer grasses and rarely use slopes over 10% when given a choice. Sheep utilize a variety of plants, while goats prefer shrubs and forbs. Sheep and goats are also more surefooted and agile, enabling them to use steeper and more rugged topography. The class (age and stage of reproduction) of grazing animals should also be considered. In some situation, yearling cattle may be more appropriate in rugged terrain than cows with calves as they are more agile and tend to travel farther. However, in other cases the opposite may be true, depending on range conditions and management goals.

Supplements — The number and location of supplements including salt, mineral, and feeds can be used to entice livestock away from overgrazed areas and onto underutilized ones. Protein and energy supplements are generally more effective in altering grazing distribution than salt alone. Supplements should be purposefully located away from water as animals tend to return to grazing following consumption rather than to water.

Fencing — The most direct way for managers to alter animal distribution is through fencing. Fences can subdivide large pastures into more manageable units or delineate areas requiring different grazing management strategies, including riparian areas or irrigated pastures. However, the expense of fencing, the need for additional water sources, and the subsequent impact on wildlife mobility should be considered before installing fencing. In general, fencing should be the "last resort" to solving animal distribution problems.

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Herding

Improved grazing distribution can result in an increase in stocking rate because more of the available forage in a pasture is grazed and more forage is produced in formerly overused areas.

Herding is a proven tool for controlling cattle distribution, but herding is more effective when cattle behavior is considered. For example, trailing to a new pasture is made easier by identifying the leaders in a herd. Leaders are individual animals that consistently initiate movements that cause others to follow. Leaders tend to be the most popular cows, that is, cows that are the preferred associates of many herd members. Herd movements are easier when ranchers begin by locating the leader cows in the pasture and then purposely herding them first, before any others in the herd. This strategy enables other cows to notice movement by the leader cows, which encourages the rest of the herd to follow, more or less on their own.

Subgroups within a cattle herd should be dispersed as a unit. Otherwise, individuals separated from their subgroup will return to their former location. A herder should purposely relocate animals to alternative sites rather than merely harassing animals to disperse from a preferred site. Mere harassment often results in cattle returning within minutes or hours to their former site. Rather than trying to disperse large numbers of cattle at once, it is better to gather only one subgroup or a few subgroups at a time and then guide them to a new site. Upon arrival at the new site, the animals should be shown the location of water, salt or supplement, and palatable forage. The herder should then remain with the animals in their new location until the group has settled. This often requires half an hour to two hours. Cattle are considered settled when their heads are down grazing and cattle within the herd are pointed in different directions. The approach is similar to when trailing cow/calf pairs to a new pasture and then waiting there to make certain that every cow has claimed its calf. The time spent ensuring that subgroups establish their new home base saves much time that would otherwise be spent repeatedly harassing animals away from their former locations. Spending this time may markedly improve the intake of supplemental feed and its effectiveness in luring cattle into certain areas of a pasture. When moving cattle to a new grazing site, it is best to move them before they have watered; when relocating cattle to new loafing areas, it is best to move cattle soon after they have watered. These strategies make cattle more inclined to graze or rest when they reach their new location, rather than immediately returning to their former location.

Cattle distribution is influenced by where cattle enter a pasture because they tend to linger in the portion of a pasture first entered. This is especially true if the individual animals are unfamiliar with the pasture. Purposely having cattle enter pastures in successive years through different access points will encourage better distribution. Cattle that return to a pasture in successive years also tend to distribute themselves more completely across a pasture due to their familiarity with the topography, available forage, and the locations of water, salt, and supplement. When first released into a pasture, cattle should be moved in small groups to specific sites. Cattle should not be released at a boundary gate and left alone to find areas upon which to congregate because, once a foraging habit is developed, it is very difficult to disrupt by herding.

Individual animals sometimes do not respond to herding, and these animals should be culled from a herd. Eliminating uncooperative individuals will help develop a group of animals that readily responds to herding, and cattle can be trained to use certain areas of a landscape even though they may prefer to use others. There are examples where diligent herding has effectively trained cattle to spend less time within riparian areas. Most, if not all, of these herds at one time or another contained cows that did not respond well to the herding, and these cows were culled for this reason. In this way, selective culling has been used to lessen cattle use in riparian areas, but if the negative reinforcement from herding were to end, riparian use by these cattle herds would likely increase.

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Selective Culling

Some scientists and resource managers have suggested that selective culling also might be used to develop a herd of cattle that prefer to graze uplands. By watching where individual cows tend to graze and culling those that spend a lot of their grazing time in riparian areas, this strategy suggests that grazing pressure in riparian areas would, over time, be reduced.

Selective culling based on such observations should be considered cautiously because its effectiveness is uncertain. Although some cows do spend disproportionately more time within riparian areas, it is possible that in their absence and without diligent herding, the vacated riparian area would simply be re-occupied by other individuals in the herd.

This occurred when a selective culling strategy was assessed on foothill rangeland in southwestern Montana. A herd of 160 cows was grazing within a 1,563-hectare (3,862-acre) pasture from late July through September. Each autumn for four years, 10% of the cows were culled that spent the most time grazing in riparian areas during the previous late summer. All of the culled cows had spent at least 50% of their grazing time in riparian sites. After four years of selectively culling the riparian dwellers, the 160 cows in the herd spent 31% of their grazing time in riparian sites. Prior to selectively culling the riparian dwellers, the 160 cows in the herd had spent 30% of their grazing time in riparian sites.

The efficacy of selectively culling riparian dwellers may depend on the degree of home range overlap among individuals or subgroups. Little or no home range overlap provides less chance for other animals to perceive the absence of the culled animals and less chance that the vacated area will be reoccupied. Home range overlap is typically low in areas where resources are plentiful, such as areas with numerous watering sites and large amounts of nutritive, palatable forage, or where dense trees prevent cows from seeing each other across large distances. However, overlapping cattle home ranges are common on western rangelands where water, shelter, and desirable foraging sites are more limited. Consequently, selective culling is less likely to work in many rangeland environments. Even in the large foothill pasture in the selective culling study, for example, home range overlap was high among cows because they could readily see each other on distant ridges and most of the herd watered together at only two or three water sources.

Selectively culling riparian dwellers is less likely to be effective when ranchers introduce additional or replacement females that were not reared in the same pasture from which animals were selectively culled. This is because animals reared elsewhere cannot return to their natal home range and may occupy the home range vacated by selective culling. Finally, livestock managers using selective culling should also make certain that replacement females selected from the herd were not raised by riparian-dwelling cows. Otherwise, the replacements will likely perpetuate the foraging pattern of their culled mothers.

Written by Rachel Frost, Montana State University

The most important decision for successful range management is determining carrying capacity and setting a proper stocking rate. Matching the number of grazing animals with the forage resource is an important management decision regardless of grazing system. Too many animals in a management unit or pasture will reduce livestock weight gain, conception rates, and body condition and cause undesired changes in the soil and vegetation.

• Carrying Capacity
• Stocking Rate

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Carrying Capacity

The number of grazing animals a piece of land can support long term while maintaining or improving the rangeland resources (vegetation, soils, and water) is called carrying capacity. The characteristics of the land, vegetation, and soil determine the carrying capacity, not the land manager. Proper carrying capacity attempts to balance between long-term forage supply and forage consumption by all grazing animals, both livestock and wildlife. Determining carrying capacity is an important goal of any rangeland inventory or monitoring program and forms the basis of stocking rate decisions. Furthermore, an assessment of carrying capacity can provide information on potential economic returns from ranch developments and forms one basis of ranch value on the real estate market. The actual carrying capacity for any management unit varies across years because annual forage production fluctuates due to variability in both the annual and growing season precipitation and temperature.

Determining carrying capacity The simplest and most reliable way to determine carrying capacity is to obtain past stocking rates and grazing management information for a piece of land and then assess the ecological status or condition of the rangeland. If the condition is good or improving, the current stocking rates are below carrying capacity. If the condition of the rangeland is declining, carrying capacity has been exceeded, and grazing management practices or stocking rate may have to be adjusted.

What if there are no historical stocking rate data available? One can estimate carrying capacity for a parcel of land in several other ways, even without historical stocking rate information. The first way is to measure annual forage production on the land and calculate an estimate of carrying capacity.

This method is useful but is based on a series of estimates for annual forage supply and animal demand. Continued monitoring of range condition and adjustments may be necessary to determine a final carrying capacity. Your local Cooperative Extension Service or Natural Resources Conservation Service office can assist you in this process.

Another way to estimate carrying capacity is to compare the land to similar rangeland with a successful history of setting stocking rates. Find out the carrying capacity estimates of the area and use those as a guideline to begin the process of determining an appropriate carrying capacity for your particular piece of land.

Trial and error is an inherent part of estimating carrying capacity. Additionally, carrying capacity is complicated by the fact that both forage production and animal intake are dynamic factors that vary with ecological site, topography, time of sampling, and plant species composition. The diets of grazing animals also vary according to animal nutritive requirements and the unique dietary preferences of species, breeds, and individuals. Therefore, carrying capacity estimates should be treated as an initial starting point for the management unit that will almost certainly be revised with continued monitoring and current environmental conditions.

Adapted from: Determining Carrying Capacity by Ken Sanders

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Stocking Rate

As stated above, the most important decision for successful range management is setting a proper stocking rate. Stocking rate is defined as the number of animals grazing on a given amount of land for a specified time. Stocking rates are often expressed in AUs/unit area (links to Animal Unit).

4 Steps to Setting a Basic Stocking Rate:

1. How much forage do you have? The first step toward determining how many animals the grazeable portion of a management unit can support is to measure how much forage the area produces. The amount of forage produced can vary greatly from year to year depending on weather; therefore, estimated forage production for determination of stocking rate should not be based on one year of forage production data. Managers can estimate the forage production of their land by mapping the management area into units of land that produce similar kinds and amounts of forage. These units are termed ecological sites or habitat types and most often will differ in soil type and plant productivity. Each unit should be surveyed to determine biomass production by 1) mowing or clipping small areas, 2) referring to picture guides to visually estimate amount of forage available, or 3) referring to site guides to estimate average productivity of the site. Only a certain portion of the biomass can be safely removed, and this depends on the vegetation and other management objectives. A common starting point is that 50% of the annual production that is potential forage can be harvested each year. Once a biomass estimate for each site has been obtained, multiply the number of acres within each site by its estimated biomass production per acre and sum these values for a total amount of potential forage produced. Finally, multiply the total amount of biomass by the percent of allowable use to obtain the total amount of forage available for livestock use.

2. How much of that forage can be used by grazing animals? (Usable Forage) Land characteristics such as topography and distance from water influence the amount of forage available to grazing animals. Forage in areas with very rough or steep topography may be inaccessible to grazing animals or used much less than forage on level ground close to water. For example, grazeable plants located two miles or more from water are essentially unusable for livestock. They represent potential forage for livestock if the animals could be enticed to use the area. All management units should be stratified into areas of available and potential forage. Areas of potential forage identify management opportunities to improve livestock distribution across a greater portion of the landscape.

3. How much forage do your grazing animals need? (Forage Demand) To calculate how much forage your grazing animals will need, you must determine the average weight of the animals in a herd or flock and the number of days the herd will graze the management unit. The average daily forage consumption of an animal — a combination of eating, trampling, and spoilage from urine or feces — will vary with the nutritive quality of the forage; however, an annual average of 2.6% is usually acceptable. For example, a 1,200-pound range cow that consumes 2.6% of her body weight requires 31 pounds of forage per day (1,200 pounds * 2.6%). When you multiply the animal's daily need by the number of days the management unit will be grazed, you obtain forage demand for that period. In the example above, if the cattle grazed the unit year round, then each cow would require 11,315 pounds (31 pounds * 365 days) of forage for the year.

4. What is your appropriate stocking rate? Now that you have answered the above questions — how many animals can you graze and for how long — to determine the number of animals that can be grazed on a management unit, you must divide the pounds of usable forage by forage demand. For example, if a management unit that is grazed year long has 465,000 pounds of usable forage, and annual forage demand per animal is 11,315 pounds of forage, then 41 cows can graze the unit for 12 months. If the grazing period is less than 12 months, then more animals can graze the area for a shorter period. A three-month grazing period would have a stocking rate of about 164 cows [465,000 pounds of available forage /(31 pounds forage/head/day * 91 days) = 164.8 head].

Administration of Fire Regimes 

" ...Institutions, not merely policies, of fire protection have rapidly and probably irreversibly undergone a metamorphosis. The evidence lies all around. Privatization, partnerships, the devolution of political decision making to more local jurisdictions, indigenous land claims, a near civil war over the destiny of the public domain- all are changing the attributes of how government administers these lands and how they cope with fire."
(Tending Fire: Coping with America's Wildland Fires. by Stephen J. Pyne, 2004, pg. 164).

 A Brief History of United States Fire Policy

From the creation of the Forest Reserves at the turn of the last century through the 1970's the USDA Forest Service was the preeminent wildland fire agency commanding the bulk of the nations firefighting resources and directing its fire research. While critics became vocal as early as the 1930's, the agency's policy during these 60 years was one of suppression (Pyne 1997). With the surge of environmental legislation in the late 1960's and the establishment of wilderness reserves, policies supported letting backcountry fires burn and reintroducing flame via prescribed fire. With this shift also came greater inter-agency coordination on fire management. By the 1990's on the heals of some devastating escaped prescribed fires and a general population increase adjacent to wildlands, the nation's resources turned to the control of fire in the wildland-urban interface. New forms of collaboration between federal, state, and local fire insitutions became essential. As one devastating fire season follows another, we now know that some fires, given current fuel loads and climatic conditions, may be beyond our control.

• Fire Policies and Legislation
• Fire Management at the Federal Level
• State and Local Fire Management
• Private institutions and Collaborative Groups

Where? How Big? How Much Money?

The earth's fire problem is one of maldistribution. There is too much of the wrong kind of fire in the wrong places or at the wrong times, and not enough of the right kind of fire at the right places and times. (World Fire: The Culture of Fire on Earth by Stephen J. Pyne, 1997, pg. 5-6)

In 2006, the largest US wildfire occured in Texas, burning over 900,000 acres of grassland. Acres burned by prescription were greatest in Alabama and Florida. In 2006 the USDA Forest Service reported spending over 1.5 billion dollars on wildfire suppression (NIFC). Wildfire is not unique to the US. Russia, Australia, and Canada also experience large and frequent wildfires (Pyne 2004). Want the latest on fires around the country and around the world? These sites provide up to the day information.

• Current U.S. Wildland Fire Information: The National Interagency Fire Center. Find out where fires are burning right now. Learn how many acres have burned each year since 1960. Learn what the annual costs have been for fighting fires. find out how much prescribed burning is occuring in your state. This site is the place to go for information.
   
• Current Global Fire Status: The Global Fire Monitoring Center. Where are fires occuring in the world? How do other countries cope with fire? The Global Fire Monitoring Center Offers Statistics, News, Maps, and other resources.

The wildland-urban interface (WUI) is the zone where structures and other human development meet or intermingle with undeveloped wildland or vegetative fuels (NIFC). Currently in the United States it includes 9.4 % of the land area and 38.5 % of all housing units and growing, with the largest number of homes in California (Radeloff et al. 2005). These areas pose the greatest threats to lives and property, pitting the fierceness of wildland fires against often indefensible homes, lacking the proper protections that could reduce fire risk. These fires often occur in locations that slip between the jurisdictions of urban and wildland fire agencies and outside effective county or rural fire districts, requiring action by outside agencies at the nation's expense (Pyne 2006, pg. 275). Such situations raise questions about who should pay for the protection of these homes from wildfire? What responsibilities should landowners have for the protection of their homes? Is building in a fire zone equivalent to building in a floodplain or at the base of a volcano? The wildland-urban interface has forced new forms of collaboration between the various fire agencies. Community wildfire protection plans now pose the greatest hope for defining roles and responsibilities before the flames come lapping.