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Written by Brad Schultz, Extension Educator, Winnemucca, Nevada

There are no clear boundaries to definitively classify rangelands. However, grouping rangeland plant species into vegetation types provides a framework for managers to assess the ecological status and trend of plant communities. Vegetation can be classified on a hierarchical scale, the broadest of which is based on climatic, physiographic, and edaphic factors across large geographical regions such as grasslands, deserts, and shrublands. Vegetation types can further be divided into groups based on major plant species. Examples include the sagebrush steppe, salt-desert shrub, juniper woodland, intermountain bunchgrass, shortgrass prairie, and tallgrass prairie plant associations. Some types of land classification systems commonly used by managers to guide research and policies and as a tool for communication are: Ecological Sites; Rangeland Vegetation Types; Rangeland Habitat Types; Major Land Resource Areas. 

Ecological Sites

An ecological site is a distinct kind of rangeland that has a certain potential to produce a distinct plant community. It is used to describe units of land that require a unique management strategy based on kind of soils, climate and topography found on the site. Currently, the most widely accepted classification system for rangelands is the Ecological Site.

What is an ecological site? An ecological site is a unique, identifiable, and repeatable patch of vegetation and soil on a landscape. Each ecological site is the product of the environmental factors that influence the development of the soil and vegetation, including disturbance regimes. An ecological site has specific homogeneous biological, physical, and chemical characteristics and has the potential to produce a distinct mix of plant species with similar amounts of annual biomass of vegetation. The basic premise is that a specific soil type based on depth, texture, horizonation, water-holding capacity, pH, salinity, and other factors is inhabited by specific plant species. The soil, therefore, is the foundation of an ecological site. If the foundation undergoes a dramatic change, the structure above will have a corresponding change.

On rangelands, ecological sites form the basic classification unit for categorizing different plant communities and their associated soils. A key concept for an ecological site is the potential natural community (PNC). The PNC is a complex concept that includes the typical disturbance regime that affects the ecological site. Many rangeland plant communities endure a periodic stand-replacing disturbance — for example, fire — that does not dramatically alter the soil but decreases or removes some plant species and lets others immediately increase. The first plant community that establishes after a stand-replacing disturbance usually undergoes vegetation change over time. If the evolved disturbance regime has an average of 50 years between events the community that typically is present after 40 to 50 years of succession is considered the potential natural community. Vegetation on an ecological site, therefore, is not static, and several community phases of the PNC may develop and eventually succeed one another. Rangeland scientists have developed a conceptual approach called state and transition models to help describe changes in community composition, vegetation structure, and ecological function with regard to management actions and environmental condition.

The biological, physical, or chemical conditions that create an ecological site can also change. When their change is sufficient to add, remove, or change the intensity, frequency, or duration of the ecological processes — for example, plant competition, hydrology, disturbance regime — that maintain an ecological site, the site can degrade to a different ecological site.

What is an ecological site description? Each ecological site has defined components that are described by range management specialists and soil scientists. The complete assemblage of these components into one document forms an ecological site description (ESD). Ecological site descriptions are intended to be clear descriptions of the features that characterize the site, making it unique and different from other ecological sites.

The format for ecological site descriptions changes with time because research and management regularly create new knowledge about the environmental variables and ecological processes that affect the formation of distinct soils and their associated PNC. Important ecological and environmental components of updated ESDs are: 1) the major land resource area (MLRA) in which the ecological site occurs, 2) physiographic features, 3) climatic features, 4) influencing water features, 5) representative soil features, and 6) plant communities. Except for the MLRA, the ESD will provide substantial detail for each parameter. The intent of an ESD is to provide landowners and managers with the environmental and ecological information they need to develop management plans, management goals, and management actions for the rangelands they manage. The content of an ESD provides the end users much of the information they need to understand the potential productive capability of their rangeland, the constraints that limit management options, and potential hazards that may occur.

ESDs are developed and housed by the USDA Natural Resources Conservation Service. Recently updated versions are often available on the Internet. Older versions, especially those still in previous formats, usually are not available electronically but can be obtained from state and field level offices of the Natural Resources Conservation Service. More detail about ESDs can be found in Chapter 3 of the NRCS National Range and Pasture Handbook.

How are ecological site descriptions developed? Ecological site descriptions are used to make decisions about how to manage rangelands. Data and information about ecological sites are combined with other resource information to improve management decisions. One of the first steps is to identify and map the soils and ecological sites on a heterogeneous landscape. Once the soils and ecological sites are mapped, managers can assess the vegetative composition and annual production of the seral communities relative to the potential plant communities that could occupy the site.

How are ecological site descriptions used? Ecological sites are distinct units of the soil-vegetation complex, but many management questions and issues occur across landscapes occupied by several ecological sites. Interrelationships among ecological sites can be analyzed at different spatial scales and the results applied at the scale appropriate for the management questions and issues being addressed. Boltz and Peacock (2002) describe six uses of ecological site descriptions: 1) describing the interactions among soils, vegetation, and land management; 2) a foundation to assess the condition of current resources and monitor changes; 3) a framework to assess management opportunities and predict the outcome of management decisions; 4) a framework for identification of knowledge gaps in vegetation dynamics; 5) a common framework for communication of resource information among disciplines, agencies, and organizations; and 6) a framework for transferring experience and knowledge.

Written by Brad Schultz, Extension Educator, Winnemucca, Nevada

The vegetation on rangeland is always changing toward one of several or more plant communities. Understanding why vegetation changes and how to manipulate that change is critical for rangeland managers to ensure that rangelands continue to provide the goods and services needed by society.

Early research about changes in plant communities across time, or plant succession, on rangelands resulted in the belief that vegetation change was linear. That is, community A changed into community B, which ultimately changed into community C, and so forth. After many decades, rangeland scientists and managers realized that vegetation change is not always linear. Changes in management did not always result in the return to the previous, more desired plant community, and normal disturbances often resulted in new plant communities that were stable and responded very little to management actions. In essence, the response of the plant communities to management and disturbance was non-linear.

Land managers need to understand which plant communities can ultimately occupy a site, given the current plant composition, the inherent potential of the soil on the site to produce specific plant communities, the probable climatic patterns and environmental conditions or constraints that will occur, and the suite of management actions available within the aforementioned constraints. To describe the non-linear vegetation changes that occur on most rangelands, rangeland scientists developed a conceptual approach called state and transition models. State and transition models use box-and-arrow diagrams to describe and understand non-linear vegetation change, or plant succession. That is, changes in community composition, vegetation structure, and ecological function are illustrated that do not follow the one-dimensional pathway, forward or backward, described in the previous paragraph.

The specific plant communities that ultimately develops depends upon which management actions are applied; the intensity, frequency, and duration of those actions; and how those management actions interact with environmental conditions and their variation across time. To help you understand the concepts behind and advantages of state and transitions models we will briefly discuss plant succession on rangelands, why the previous models used to describe plant succession on rangelands do not work and can result in poor management decisions, the components of a state and transition model, and the structure of a complete state and transition model. Data and information from a Wyoming sagebrush ecological site will be used to illustrate the problems with previous plant succession models and the components of state and transition models.

Forces that Shape Rangelands. Rangelands are a dynamic landscape, composed of many resources, that produce many products. The rangeland landscape and its resources are constantly being modified by a suite of non-human forces, including:

• Grazing

• Fire

• Climate or Weather

Humans also modify rangelands directly through development (e.g., energy, mining, and transporation and communications infrastructure) and recreation. People also affect the other forces of change by introducing invasive species, controlling or igniting fires, managing grazing and potentially impacting the climate and weather patterns through human caused changes in atmospheric chemistry .

Managers need a way to predict how management practices or natural disturbance will impact the vegetation on rangelands, so they developed State and Transition Models. State and transition models are box-and-arrow diagrams used to describe vegetation change, or plant succession, from a specific disturbance based on the current vegetation community, the soils and climate of a site.

Rangelands are dynamic ecosystems that  produce a wide variety of goods and services desired by society, including livestock forage, wildlife habitat, water, mineral resources, wood products, wildland recreation, open space and natural beauty. In order to continue to provide those goods and services, rangelands must function ecologically, in other words, they must be able to capture water and nutrients and convert them into plants

Written by Rachel Frost, Montana State University

Herbicides that interfere with and/or disrupt the biochemical or physiological processes unique to plants. Herbicides typically decreases the growth, competitiveness, and/or seed production of unwanted plant species while providing opportunities for desired species to increase in number, size and productivity. Herbicides, therefore, are valuable tools for controlling unwanted plants on rangelands.

When properly applied, herbicides can provide a window of opportunity for desired plants by removing or suppressing populations of weeds. However, using herbicides alone to control weeds seldom results in successful long-term control. Once weed species are removed from a site, the area must be revegetated with desired species that can competitively exclude the potential weed species. Herbicides are most valuable when they are one component of an integrated weed management plan that focuses on replacing of weeds with desired species, proper grazing management, and management actions that reduce the risk of new infestations.

• How Herbicides Work
• Successful Weed Management with Herbicides
• Herbicide Mode of Action
• Herbicide Fate in the Environment

How Herbicides Work

Written by Rachel Frost, Montana State University

Application. Most herbicides are applied either pre-emergence, before the weeds emerge from the soil and begin to grow, or post-emergence, when weeds are already growing and easily located. Both pre- and post-emergent herbicides are used on rangelands. Pre-emergent herbicides have a high degree of soil activity and are readily absorbed by the roots of both seedlings and mature plants. The target plants are killed shortly after they germinate and/or shoots emerge from the soil. Pre-emergence herbicides are effective in controlling annual weeds, such as cheatgrass, and may be applied following disturbances like wildfire to prevent weed establishment from seeds.

Formulation. A herbicide formulation is how a particular herbicide is packaged for distribution. The formulation includes both active ingredients — the chemical that harms or kills the plant — and inert ingredients such as solvents that enable them to penetrate leaf tissue. The most common formulation of rangeland herbicides is a concentrated liquid that can be diluted with water and sprayed on the target species. Water is the most commonly used carrier of herbicides for rangeland application. It is cheap, universally available, and works with a wide variety of herbicides. However, hard water — water with high levels of calcium and magnesium salts — can decrease the activity of certain herbicides with an ionic charge. A few rangeland herbicides are formulated as dry granular material or pellets that are applied directly to the soil surface without dilution in water. Because it is not diluted prior to application, the active ingredient in dry formulations is much less concentrated. These herbicides require precipitation to move the active ingredient into the soil to the root system, where it is absorbed and translocated to the plant's growing points.

Selectivity. The selectivity of an herbicide is determined by the plant's ability to metabolize the active ingredient and render it harmless. The different metabolic processes in plants are capable of inactivating certain herbicides and rendering them harmless. For example, grass species are capable of metabolizing phenoxy herbicides, while broadleaf plants are not. Phenoxy herbicides, therefore, kill broadleaf plants but have no effect on most mature grass plants. Seedlings are the growth stage most susceptible to chemical control. An herbicide that does not harm mature plants may kill most of the seedlings of the same species. It is important that anyone applying an herbicide read the herbicide's product label before they apply the chemical. The product label will inform the applicator of the herbicide's level of selectivity and how that may change with plant maturity or the dosage applied. Understanding an herbicide's selectivity is important because land managers often want to remove one or more species without adversely affecting the non-target species.

Translocation. Once an herbicide has been absorbed by a plant, the movement of the active ingredient throughout the plant is referred to as translocation. Systemic herbicides are absorbed by the plant's roots and/or foliage and are translocated to distant parts of the plant, including root buds, growing points (meristematic tissue), and other reproductive structures. The active ingredient typically accumulates in these critical growth areas and interrupts the important metabolic processes that keep the plant alive. Systemic herbicides are very effective at controlling perennial weeds that regrow from buds on the roots or root crowns. To kill perennial plants that resprout from belowground buds, all of the buds have to be killed. Systemic herbicides that are translocated through the phloem are most commonly used on rangeland. Contact herbicides have very limited movement within the plant and kill only the tissue that comes in direct contact with the herbicide. Although contact herbicides can effectively top-kill a perennial plant, the herbicide's inability to be translocated to the root system allows the plant to regrow the following year. Contact herbicides are most effective against annual plants.

Successful Weed Management with Herbicides

Written by Rachel Frost, Montana State University

Proper attention to the following three basic principles will improve the effectiveness of herbicides and decrease potential negative impacts to non-target species, the environment, and the applicator:

• Choose the right herbicide for the job - Herbicides vary in the way that they affect plants and in the type of plants that they affect. Non-selective herbicides kill or suppress all vegetation, while selective herbicides kill some plants but not others. For example, a broadleaf spectrum herbicide like 2,4-D kills only broadleaf forbs and shrubs and does not harm grasses and sedges.
• Apply the herbicide at the right time - Herbicides need to be applied at the correct stage of plant growth to maximize effectiveness. For example, annual weeds should be treated before flowering to prevent seed set. Movement of the herbicide through the plant's system to the roots is essential for perennial weed control, so herbicides are most effective when applied to perennial plants when they are moving carbohydrates to the roots.
• Use the proper application technique - Herbicides can be mixed in a variety of formulations, including liquids, powders, or pellets. The label is a legal document that provides information on the proper use and application of herbicides. Labels provide detailed information on the correct formulation, rate of application, recommended carriers or additives, and safety precautions for that specific herbicide.
  • Additional site characteristics such as soil type, slope, and the existing vegetation — both target and non-target plants — should also be considered when selecting the herbicide and planning the application process.
  • Always read and follow the herbicide label directions.
  • ​Check with your local weed professional or Cooperative Extension agent for help in selecting the proper herbicide and application procedure for your target species. Remember to calibrate your sprayer to ensure accuracy in application rates and to save money.

Herbicide Mode of Action

Written by Rachel Frost, Montana State University

The mechanism by which herbicides actually kill plants is known as the herbicides’ mode of action. Each mode of action focuses on a specific site of action, which is usually a single enzyme or enzyme pathway that is essential for plant growth. Herbicides kill plants by inhibiting or affecting these essential enzymes or pathways.

Growth-regulating herbicides. The most widely used herbicides in rangelands are growth-regulating herbicides. Growth-regulating herbicides upset the normal hormonal balance that regulates processes such as cell division, cell enlargement, protein synthesis, and respiration. Although usually applied to the foliage, this group of versatile herbicides is also effective in the soil. This increases the effectiveness of the herbicide as any of the chemical that does not land on the foliage can be percolated into the soil with rain and taken up by the weed roots. Growth-regulating herbicides can be classified as phenoxy herbicides, benzoic acids, and carboxylic acids.

Photosynthesis inhibitors. Photosynthesis inhibitors do just what their name implies: They inhibit photosynthesis, preventing plants from converting light energy from the sun into sugars used for food. Photosynthesis herbicides are used primarily to control broadleaf plants but can be marginally effective against annual grasses.

Amino acid synthesis inhibitors. There are two main types of amino acid synthesis inhibitor herbicides: selective and non-selective. Selective amino acid synthesis inhibitors control both broadleaf plants and grasses, have both soil and foliar activity, and are virtually non-toxic to mammals and most non-vegetative life forms. Amino acid synthesis inhibitors kill the plant by binding to a specific enzyme and preventing the plant from synthesizing essential amino acids. Non-selective amino acid inhibitors, such as Roundup, control a broad range of plants, including grasses, sedges, and forbs. They bind tightly to soil clay and organic matter and do not move through the soil profile.

Herbicide Fate in the Environment

Written by Rachel Frost, Montana State University

What happens to herbicides after they have been applied to rangeland? Do they remain in the soil, eventually accumulating to hazardous levels? Or do they move into the environment, causing off-site problems? In reality, most herbicides do not survive in the soil for very long, nor do they move very far through the soil from one area to another. The environmental persistence of a herbicide depends on the rate of application, the method of application, soil type, weather, and characteristics of the chemical. Still, herbicides are subject to the same biological processes of decomposition as any other compound.

Written by Rachel Frost, Montana State University

Mechanical control on rangelands is defined as "the use of a tool to remove or destroy above and/or below ground plant material." There are numerous different ways to treat rangeland mechanically. The form of mechanical control that is best suited to a particular situation depends on:

1. characteristics of the plants
2. the size of the infestation (this is directly related to cost)
3. availability of the equipment
4. soil characteristics
5. topography
6. current and intended land use

Mechanical tools commonly employed to manage rangeland vegetation:

Chains. The use of chains to alter rangeland vegetation is called "chaining". Chaining involves pulling a large chain, most often a section of marine anchor chain, between 2 tractors. Vegetation is either pulled out of the ground by the roots or broken off at ground level. Chaining is most effective on trees as herbaceous material is generally not seriously damaged. Chaining provides relatively quick results and allows large areas to be treated at a relatively low cost, however, it causes substantial soil disturbance that can lead to compaction or erosion. Trees or shrubs that resprout may require additional treatment with herbicides or fire to actually kill the plants.

Root Plows. A root plow is a heavy-duty, V-shaped blade that is pulled behind a tractor to sever the roots of trees below the bud zone. Root plowing can control up to 90% of target plants when properly implemented; i.e. the blade is at the correct depth and it is done at the proper time of year. Unfortunately, root plowing also kills most herbaceous plants on site, especially when operating in areas of high tree density. Selective plowing can be used to sculpt the vegetation, improve wildlife habitat and enhance multiple use values on rangeland with fertile soils.

Mowers. Mowing is generally applied to herbaceous vegetation to immediately remove biomass from an area. It can be used to prevent seed production in patches of invasive weeds or to increase visibility and ease of travel such as along highways or in recreation areas. Mowing causes minimal soil disturbance, but does not necessarily kill the target plant and may cause harm to desirable vegetation as well. Repeated mowing may reduce resprouting trees and brush, however, it is most often combined with other treatments to achieve maximum control. Mowing is not suitable for rocky ground or areas with dense stands of large diameter trees.

Rakes. Rakes are often used after chaining or root plowing to smooth and prep the site for revegetation. Specially designed rakes allow trees and brush to be stacked with minimal soil in the pile.

Written by Rachel Frost, Montana State University

Cultural management tools involve changing the timing, intensity or duration of a land use or management action to achieve a desired vegetation composition or structure. Targeted grazing, fire and reseeding or planting desirable vegetation are all forms of cultural control. These management practices can be implemented at different seasons, intensities or durations to accomplish clearly defined vegetation management goals. Cultural control is most often employed to manage invasive herbaceous weeds. Planting desirable, competitive plants that can capture soil and moisture resources, preventing weeds from obtaining these resources, and limiting their abundance is an example of cultural control on rangelands.

Written by Rachel Frost, Montana State University

Successful rangeland weed management plans should be an integrated process that involves the use of several control methods, combined with a well-planned strategy to reduce the impact of weeds on rangelands. The following steps outline a complete integrated strategy for protecting and enhancing rangelands threatened by weeds.

Inventory and mapping - Before a management program can be implemented, the extent of the problem must be determined. An inventory provides information on the weed species present, the size and density of the infestation, and the characteristics of the site including soil and vegetation complexes. This information can also be used to identify areas of potential invasion or possible routes of introduction to a specific land area. Once the information is gathered, it should be incorporated into a map to facilitate planning and implementation of control measures.

Planning and implementation - During the planning and implementation phase, problems are identified and prioritized and paired with appropriate solutions. The economic feasibility of the plan should be evaluated to ensure there are adequate resources to implement all phases of the weed management plan, including post-treatment monitoring and evaluation.

Preventing weed encroachment - By far the most cost-effective method of weed management is to prevent the introduction of weeds in the first place. Prevention programs involve limiting weed seed introduction and dispersal, minimizing disturbance, and practicing proper management. Specific ways to prevent new weed introductions are:

• Use certified weed-free hay, feed grain, straw, and mulch;
• Avoid driving through weed-infested areas and always wash the undercarriage of a vehicle that has been in weed-infested areas;
• Avoid grazing when weeds have mature seedheads. 
• Move livestock to a holding area for about 14 days after grazing a weed-infested area and before moving them to a weed-free area;
• Ask hunters and hikers to clean their clothes and equipment prior to coming on your land, especially if they have been in a weed-infested area;
• Minimize soil disturbance when possible; and
• Manage for vigorous, diverse vegetative communities capable of competing with weeds.

Early detection and eradication - Early detection of new weed infestations can facilitate complete eradication of a serious noxious weed before it has a chance to widely establish on rangeland. Weeds spread by establishing small satellite infestations, the advancing front lines of the main invasion. Early detection of these small infestations can lead to successful eradication or total removal of the weed from the area.

Containment of large infestations - Once weed infestations become too large to eradicate, containment is the most cost-effective strategy. Containment of large-scale infestations is beneficial because it preserves uninfested rangeland by treating the borders of existing infestation and preventing the infestation from spreading beyond its existing boundaries.

Select appropriate control techniques - No single weed control technique is appropriate for all areas in a management unit. Control techniques must be chosen according to available economic resources and the environmental considerations of the area. Specific things to consider when selecting the most appropriate control technique include: the target weed species, effectiveness of the control technique, availability of control agents such as insects or grazing animals, land uses, timeline of control, environmental considerations, and relative cost of the control techniques. A combination of control techniques may provide better control than a single technique.

Revegetation and proper grazing management - Revegetation with desirable plants may be necessary on sites without an understory of desirable species. These newly established species can minimize the invasion of rangeland weeds and improve forage quality of the site. A grazing plan with the goal of moderate grass utilization should be established on any management unit with a weed control program. The grazing system should allow ample recovery time between grazing periods for plants to recover and to promote litter accumulation, important for maintaining a health plant community.

Monitoring and evaluation - Any time a management program is initiated, monitoring and evaluation are the keys to determining program success and identifying needs for change in the program. Monitoring involves making observations, collecting data, and keeping detailed records. Ideally, monitoring will detect changes in both weeds and desirable plants, as well as biological control agent populations and soil characteristics such as erosion, bare ground, and compaction. Many rangeland weeds are difficult to control and require a long-term commitment on the part of the land manager to suppress or eradicate the weeds. The adoption of integrated weed management (IWM) strategies is the best way to protect uninfested rangeland and reclaim land with existing weed populations.

Monitoring is the best way to evaluate what impact the management strategies of your operation have on the rangeland. Pasture and rangeland monitoring should be a systematic, structured approach to tracking changes in plant communities over time. Before you begin the process of monitoring, it is important to understand why you are monitoring and to establish some well-defined goals for your monitoring program.

Setting a Monitoring Goal

• Why Monitor
• Where to Monitor
• What to Monitor

Why Monitor Rangelands

• Early Warning: Rangeland health deteriorates before livestock production or other uses decline. Further, changes in rangeland health usually occur gradually. Often human memory cannot detect changes until reminded by a historic photograph or some other artifact. Monitoring can tell you if you are moving in an undesirable direction in time to make a necessary change.
• Know if You are Reaching Your Goals? Monitoring will reveal if you are truly meeting your management goals and objectives, and help evaluate the benefits received from changes in management or range improvements.
• Have Data to Back You Up: Well-designed monitoring programs provide a record of responsible stewardship and success stories that can defend your management, and/or encourage other land managers to monitor.
• Enrich Your Knowledge: Monitoring can help you learn more about range plants and how they interact with each other and respond to grazing.

Where to Monitor

Select a monitoring location. For many, deciding the location of plots seems to be the hardest part of monitoring. Fortunately, there are some basic guidelines we can follow to ensure that our monitoring locations are in line with our goals and objectives and will provide information that truly reflects what we want to monitor.

Note that if you are monitoring on a public allottment and setting up new plots, it is essential to coordinate among permittee (if managing livestock) and range conservationists to agree to a location. Make sure the location(s) reflects areas of resource concerns. The data you collect will only be as meaningful to the degree that you agree on where to monitor, and agree that this location reflects resources concerns of all parties managing an allottment. 

Start with the big picture. Not all rangeland is created equal, and we should compare apples to apples. There are several ways to classify land areas: such as by land use, vegetation (current or historic), soils, or climate. The most current and widely used rangeland classification system is the ecological site. An ecological site — also referred to as "range site" — is an area with similar soil and climate conditions. These conditions determine the kind and amount of vegetation produced on that site. Monitoring sites should be selected to represent the different types of ecological sites on the unit.

Now we have to ask the more specific question of where within these ecological sites we are going to establish the monitoring plot. The selection of study site should clearly reflect the management or monitoring objectives. For example, if monitoring riparian vegetation, the monitoring site should be located in a riparian area.

Selection criteria. Criteria used for selecting sites are generally based on seral state of plant community, topography, location of water, fences and natural boundaries, areas of animal concentration, and presence of species of interest. Also consider kinds of statistical comparisons or intended interpretations.

All these criteria help us to identify key and critical areas to monitor.

• Key areas are a portion of land which serve as an indicator of land conditions, trends, or degree of seasonal use by animals because of location, grazing or browsing value, or topography.   These key areas are considered indicators of what is happening on a larger area as a result of on-the-ground management actions.

• Critical areas are units that contain unique or special values, such as fragile watersheds, sage-grouse nesting grounds, riparian areas, and habitats with rare plants.

Remember, monitoring sites must always be clearly mapped and documented. In other words, use GPS, explain somewhere in your survey notes why and how you selected the sites for evaluation, and consider marking it with a T-post or other marker. 

What to Monitor

Vegetation and Soil Attributes. There are many ways to measure plants and vegetation, but, there are only about 6 "attributes" that are commonly measured. Vegetation attributes are characteristics of an individual plant, plant species, type of plant (e.g., grass, forb, shrub), or plant community that can be measured or quantified. That is, how many, how much, or what kind of plant species or type are present. The most commonly used attributes are:

• Plant species or type - Which species or what type of plant is it?
• Frequency - Is the plant there or not?
• Density - The number of plants per unit of area.
• Biomass - How much do the plants in a given area weigh?
• Cover - How much of the ground surface do the plants cover? This can be stated as an absolute spatial amount (e.g., 24-m2) or as the percent of an area.
• Structure - How tall were the plants and how were branches and leaves arranged?

We can also make observations about the health, condition, or vigor of individual plants or plants communities, how much of the current year’s growth was used by grazing animals. And we can combine the above attributes to create variables such as species composition, biodiversity of the site, or similarity with historic measurements or other sites.

Photopoints. Properly located photopoints can provide useful information in addition to any other monitoring that is done. Photos of the same area, across time, should be taken from the same point, in the same direction, at the same time of year or growth stage and day, and with the same focal length. This helps insure high comparability among pictures across years. Ideally, a stake or other marker is placed in the ground to facilitate repeat photography. Care should be taken to use stakes that will not harm animals or people or attract animals to the site. Landscape and close-up photos provide useful information. Photopoints should be located in key areas that will reflect changes in management actions. To be most useful, the photographer should use a written card describing the location, date, and other useful information that is placed in the field of view. The photographer should keep notes on anything observed at the time of the photo.

Comparing photographs (close-up or general view) of the same area taken over a period of years helps document changes in the soil and plant community.

Riparian Areas. The ribbons of green between the uplands and the water are riparian areas. The green vegetation and cool shade make these areas attractive to livestock and wildlife. Therefore, use of plants in these areas should be closely monitored to ensure adequate and appropriate vegetation exists to maintain ecological processes.

Grazing Records. Records of where and how long livestock graze in an area can determine if an area is being overgrazed or underutilized. Monitoring the amount of forage used by livestock each year, and where in a grazing allotment that use occurs,  will help determine if changes are needed in stocking rate, the grazing schedule, the location of supplements, or changes in management to improve the distribution of livestock. Various monitoring methods have been developed to measure grazing animal use. The two main methods are utilization and stubble height.

• Utilization by grazing animals is the proportion of current year forage production that is eaten or trampled. Utilization is an index of grazing impact to the land that can help a rancher achieve his objectives. Measuring utilization on 2 to 3 key forage species each year will help you understand how your animals are grazing in an area and how much they are consuming of key plants. It will tell you if you need to move animals out of a pasture sooner or if some areas are receiving excessively heavy or insufficiently light grazing.
• Stubble height measures the height of the vegetation left at the end of the grazing season. The target amount of stubble left is normally based on management objectives.

Climate and Weather Patterns. Temperature and precipitation records can provide information that helps understand why the particular changes documented by a monitoring program occurred. Changes in vegetation, soils, and riparian areas can occur from many processes, not just livestock grazing or other land uses. Extreme weather events, or longer term changes in the climate, particularly the amount and timing of precipitation, can have profound effects on plant communities across time. A good understanding of how your rangeland responds to precipitation patterns can improve your ability to make needed adjustments in stocking rate or grazing system.

Data on precipitation and climate are available at the sites below, and also available through state or local resources. 

Inventory, unlike monitoring, refers specifically to ​a point-in-time. ​When ecologists, range management professionals, or others talk about inventory, they are referring to a point-in-time measurement to assess the condition of a resource. 

For example, ecologists may inventory the population of a rare plant. Or, range managers may inventory the condition of resources on a ranch. Inventorying is the systematic acquisition and analysis of information needed to describe, characterize, or quantify rangeland resources. Inventories can be used for mapping the extent and location of various rangeland resources such soils and vegetation. Inventory data may also be interpreted to assess ecological status of these resources. 

The actual type of data collected during inventory may not actually differ from the type of data collected during monitoring, but the big difference is that monitoring is repeated. Often, inventory data may be a baseline that informs future monitoring.

“Local knowledge” refers to a body of knowledge held by an individual or group of people about ecological systems, based on personal and/or cultural experience and observation. Local knowledge can be contrasted with knowledge that is primarily derived from a formal institution or specialized field of research. Local knowledge has much in common with traditional ecological knowledge (TEK), but the two are not synonymous.

Berkes (2008) defines traditional ecological knowledge as “a cumulative body of knowledge, practice and belief, evolving by adaptive processes and handed down through generations by cultural transmission”.  Local knowledge can be obtained through direct experience with the land but does not imply a culturally embedded and inter-generationally transmitted knowledge base that incorporates values, institutions and practices as well as biophysical observations. Traditional ecological knowledge is also experiential knowledge but it is culturally embedded, inter-generationally and socially transmitted and almost always includes a much wider set of beliefs, values and institutions that are inseparable from the other components of traditional ecological knowledge.

Both local knowledge and traditional ecological knowledge are not stationary. Knowledge can evolve, change and accumulate with new experiences and learning, as well as interactions with other forms of knowledge, including science. Both local knowledge and traditional ecological knowledge are useful and important sources of information, not only to those who have this knowledge, but also to science and understanding ecological change. For example, local knowledge and traditional ecological knowledge can fill in gaps where quantitative data may not exist, can provide important context about landscape history and management, and can engage local populations in decision making processes about ecological management. Many studies in the US and beyond have documented local knowledge and traditional ecological knowledge held by pastoralists, ranchers and others. Methods for documenting and collecting local knowledge often come from social science, and include techniques like surveys, interviews, and focus groups.