Rangeland Management Exam 1

Akasha Faist NRSM360 Exam 1 Study Guide

Know what a rangeland is versus isn’t, and why

It is a land-use type that has many land uses. It must have a naturally growing ecosystem (grasslands, shrublands, etc), is grazed or has the potential to be, variable climates, and storage (carbon storage sites, water, etc)

Rangelands are NOT barren desert, closed-canopy forests, highly managed pasutres and farmland, covered by solid rock or concrete (urban) or glaciers

Understand roughly how much of the terrestrial land surface area and Montana is considered

rangelands.

54% rangeland covering the terrestrial land surface and roughly 70% of MT is classified as a rangeland

Know the difference between a cultivated pasture and a rangeland

A pasture has high cultivation that is used to manage vegetation, generally introduced or non-native forage species, usually have irrigation or fertilization to increase yield, and managed by agronomic rather than economic principles

Be able to explain what RM is and the different interpretations and definitions of RM.

Rangeland management is a planning, implementing, and assessing process that protects or improves the long term productivity of the resource. Different types of RM include traditional/agricultrural, ecological/conservation, or multiple-use definition.

Be able to describe how and why Rangelands are considered a multiple use system

They are a multiple-use system because they simultaneously yield a diverse mix of ecological, economic, and recreational goods and services that must be balanced to prevent resource damage

Be able to list the three components of management as discussed in this class

• Planning

• Implementing

• Assessing

Be able to generally discuss what is guiding our management decisions and how we need to balance

science and art to do so

Managers use a management framework that’s built on -

• Wants

• Needs

• Traditions

• Hunches

• Etc

Know some broad challenges rangelands face

• Unsustainable grazing practices

• Damaging fire regimes

• Invasive plant species

• Global climate change

Be able to provide examples of different types of rangelands (as described in the lectures and

readings)

Grasslands, desert shrublands, savanna woodlands, forests (open-canopy), tundra

Know why many consider rangelands important and provide examples of the reasons why

Cover a big amount of the earth’s surface and support vital ecological and human livelihoods. Provides global food security and essential ecosystem resources like carbon storage, and also houses lots of biodiversity and wildlife habitats

Know the levels of ecological organization

Organism —> population —> community —> ecosystem —> biosphere —> biome

• Be able to identify where the rangeland biomes fall in the annual precipitation and average

temperature comparison (e.g., the Whittaker biome diagram presented in lecture and Holechek

figu

Know how many of the WWF 14 terrestrial biomes rangelands fall into

Seven of the 14 are considered rangelands

Be able to describe what the general biomes are and the differences between them

• Grasslands = dominated by grasses and herbaceous plants

• Savanna = tropical or subtropical grassland with scattered or an open canopy of trees, high temps, dry in winter and summer

• Shrubland = an area made of shrubs, can be spatiotemporally transitional between grasslands and forests

• Woodland = open stands of trees with crowns not usually touching

• Tundra = cold, harsh climates w/ freezing temps for most of the year

Be able to describe why deserts are often considered outside of the primary WWF “biome”

generalization

They are usually considered outliers because they are classified with their aridity index rather than just rainfall, and they have a severe temperature disconnect from other biomes

Be able to describe the overlap between rangelands, grasslands, and drylands and the

similarities/differences between them

They overlap because they’re defined by limited rainfall, open landscapes and lack of dense forest cover. An overlap occurs because climate drives vegetation, which in turn determines land use. I’m not really sure what else to put for this one…

Provide potential examples of rangeland management prior to the Livestock Industry proliferation

• Pastoral tribes in Eurasia and Africa grazed livestock for thousands of years

• Fire and other management tools were used by indigenous people globally

• Used for survival and other cultural reasons

Be able to explain why during the Livestock industry proliferation RM was formed (i.e., tragedy

of the commons)

• Lots of free public land (treated as a “commons”) had no formal ownership or grazing regulations

• Since grass was free, sheep and cattle barons wanted to graze as many animals as possible

• This led to severe overgrazing and the big “die-up” of lots of these animals since there was no more food for them… this evolved to the birth of rangeland management as an applied science

Know big events that directed RM as we know it today

• Tragedy of the commons

• 1916 Clementstian succession

Know what succession is and the difference between primary and secondary succession with the

possibility of giving examples

Succession is the orderly process of development involving changes in species composition and community processes over time. Primary succession= where plants and animals first colonize a barren habitat. Secondary succession = Begins after a major/moderate disturbance

Know what the Range model is and how it may not follow succession in the strict sense

The Range Model is a classical ecological framework that is historically used in RM to assess the health and productivity of the rangelands. It fails to follow strict succession because it has irreversible thresholds, soil degredation and loss of an ecosystem function, and permanent disruption of invasive species

Understand what retrogression is and what causes it

Retrogression is the gradual degredation of a plant community away from its most stable, diverse, and ecological potential. It usually happens because of things like overgrazing, over-resting, or changes in fire regimes

Be able to list and describe the different postindustrial rangeland management approaches as they

have changed over time and how they relate to the sustainability of a system

Exploitation - caused the “range problem” then to

Steady state management = maximize sustainable yield of specific goods that are most highly valued then to

Ecosystem management = focused on planning for integrated ecosystems as well as solicitation of more diverse stakeholder feedback then to

Resilience based management = recognizes the inevitability of change and seeks to guide change to

sustainably provide multiple ecosystem services for society.

Know what we mean by “plant structure/pattern” and “plant function/process”

Plant structure is talking about what is there, and plant function is talking about the process, so cycles, interactions, and mechanisms of change

Be able to explain why knowing plant characteristics matters for RM

The plant morphology and plant function and structure matters for RM because it can describe what is there and what type of life the range will support

Know the primary plant functional groups we discussed in class and key components of each of

them

Grasses (herbaceous, non-showy flowers)

Grass-like (rushes and sedges)

Forbs (herbaceous, showy flowers)

Shrubs (woody, several main stems)

Trees (usually single stem)

Understand what photosynthesis is and the broad differences between the three photosynthetic

pathways.

Photosynthesis —> process to convert light energy into chemical energy

Transpiration → process of water movement through a plant and its evaporation

Three photosynthetic pathways are C3 Photosynthesis (most plants) C4 Photosynthesis (~3-5 of all vascular plants, reduced photorespiration adaptation) and CAM Photosynthesis (~3-7% all vascular plants, separates and store photosynthesis processes by time)

Know what plant phenology and plant life cycles are, and the differences between them

Phenology: Periodic plant and animal life cycle events and how these are influenced by seasonal and interannual variations in climate and habitat

Life history: describe an individual plants life, growth, reproduction, and death

Understand how the spatial scale of assessing vegetation can matter for management actions

Evaluating vegetation at the wrong scale can lead to wasted resources, wasted funds, or ecological damage, so it’s important to assess to the correct scale

Know what NPP is

Net Primary Production

Know how precipitation can impact a system and how the total amount versus seasonal distribution,

or event characteristics may influence that.

Precipitation impacts a system by altering its water balance, chemical composition, and physical structure. Total amount is volume which is baseline water availability for a system and seasonal distribution is timing which determines system synchronization (this is what google told me.. I am still kind of lost on this)

Be able to describe how average temps may not tell the full story and why maximum and min temps

may be better at helping guide managemen

Maximum and minimum temperatures provide a more accurate picture for management because they reveal the actual environmental stress boundaries that systems endure

Know how slope and aspect may influence vegetation

Steep slopes limit heavy equipment and aspect influences vegetation type. Rocky soils and bedrock need adequate soils for plants

Be able to describe why we should consider soil in rangeland management.

It’s essential because healthy soils drive water infiltration, nutrient cycling, and long term forage productivity across the landscape

Know the main components of soil

Mixture of mineral matter, organic matter, water, and air

Be able to list and describe the primary inorganic particles of soil (i.e., soil texture) and what SOM

is (and if it is calculated in soil texture

Sand, silt, and clay. SOM is soil organic matter and it is NOT calculated in soil texture

Know the basic physical soil properties discussed in class

Parts of soil are aggregated together through key processes which are physical, biological, and chemical

Know what CLORPT is and the different components that make up ClORPT

CLORPT is the 5 forces that create soils

CL = climate

O = organisms

R = relief

P = parent material

T = Time

Be able to list the three primary soil orders found in US rangelands

Aridisols = arid (dry) low organic content

Entisols = no diagnostic horizons, highly variable

Mollisols = grassland ecosystem

Be able to describe how soil map units could help rangeland ecology and management

Soil map units provide the spatial framework needed to link underground physical properties with aboveground ecological potential

Know what site potential is and how that may be influenced by terrain, climate and soils and how

our management may further influence it.

Site potential = the inherent ability of a site’s productivity

Know the five major animal types considered to live on the range

Mammals, birds, herps, fish, and insects

Know the general terminology of what makes and animal wild domestic or feral and be able to

provide examples

Wild animals = exist in a natural state (think bison or bighorn sheep or something like that)

Domestic = become accustomed to human control and provision

Feral = domesticated animals that have been allowed to revert into a wild state (feral cats or feral pigs)

Be able to define what a habitat is and the four basic elements discussed

Habitats are the “home” of the species. Four basic elements are food, water, cover, and space

Within the four basic elements of a habitat be able to provide examples of what constitutes each of

the four elements and how that may differ across different animals

Food = energy, nutrient, minerals.. diet preferences range between grass, forbs, and browse between differetn species of grazers

Water = Water requirements vary per animal

Cover = Shade, shelter, visual obstruction, also relates to grazing intensity

Space = breeding and nesting, home range, social intolerance/territories, disease transmission interactions

Know the general difference between habitat restoration and ecological restoration

Habitat is more specific, ecological restoration is on a much broader scale

Be able to describe how grazing intensity can influence different animal species and how we may

need to use that in our management actions

It directly shapes habitat structure, plant composition, and the availability of resources for diverse animal species

Know the different type of animal relationships discussed in class (e.g., who is benefiting and who

isn’t)

Know what forage and browse are

Forage = plants or parts of plants eaten by livestock and wildlife

Browse = leaf and twig growth of shrubs, woody vines, trees, cacti, and other non-herbaceous vegetation available

Be able to describe how plant phenology relates to forage quality and the different vegetative

phases across different systems and functional groups

It directly dictates forage quality by controlling the balance between nutrient concentration and structural fiber as plants mature. As plants transition from early growth to maturity, forage quality declines.

Know how forage quantity changes over the season

Follows a distinct or more linear growth curve with a major peak in spring, a dip in summer, and decline in winter and fall

Be able to describe the best time to graze taking both forage quantity and quality into account

Usually when forage reaches “stage 2” which is when forage reaches adequate height (6-12 inches) and when quality and quantity intersect at their peak.

Know what the maintenance animal requirement is, its different components, and what is

considered in this requirement as it relates to nutrition.

Maintenance = basic metabolism + minimum movement + foraging

Know how maintenance requirements may differ across different animals, and different seasons

and, if applicable, why that is

They vary drastically across animal species and seasons because animals possess different physiological strategies to manage their body temperatures, activity levels, and reproductive cycles

Be able to state different requirements that put animals above the maintenance phase and how this

may differ across both animal and environmental characteristics

Level of activity = standing 15% greater than lying down

Environmental conditions = Cold environments require energy for maintenance; hot environments require water for perspiration

Growth = young animals and gestating females; 10-15% increased requirements

Lactation = greatest energy requirement timeframe for mature females

Be able to compare and contrast the supply and demand cycle for reproductive females (annual

demand) and the forage supply, and how that changes over the different seasons

guys her slides have no information on them I am #lost but hope these photos help! I think it is just saying that forage supply increases when birth and the weaning period are occuring.

Know potential reasons how to meet demands if supply isn’t available, as discussed in class (i.e. how can management meet demand?)

• Manipulate vegetation to meet animal needs (palatable shrubs and plant diversity)

• Feed supplements (hay, grains, energy supplements)

• Stock conservatively - set demand well below supply

Know what the stocking rate is and how it relates to carrying capacity

Stocking rates are “forage demand” while carrying capacity is “forage produced”.

Carrying capacity = The number of animals that a piece of land can support on a long-term basis without causing damage to the ecosystem. Does not equal stocking rates

Know the difference that ruminants vs hind-gut fermenters each and roughly what we are using as

a baseline for this class

Ruminants eat 2.5% of body weight/day in dry matter of forage and hind-gut fermenters eat 3.0% of body weight/day in dry matter of forage.

Understand the differences between supply and demand when refering to stocking rages in RM

Forage supply represents the available plant biomass produced by the land and animal demand represents the amount of forage consumed and impacted by grazing livestock.

Know what an AU and AUE are

AU = Animal units 1 AU = 1000 lbs of grazing animals (ruminants)

AUE is animal unit equivalent

Know what an AUM is and how it is calculated for a grazing ruminant or a hind gut fermenter.

AUM is animal unit month, meaning it’s the amount of forage that an AU will eat in a month.

Each AU = 1,000 lbs x 2.5% = 25 lbs/day

AUM = 25 lbs x 30 days= 750 lbs

Be able to list the four steps of the forage-demand method used for setting stocking rates

1) Calculate usable forage supply

2) Adjust for accessibility

3) Calculate forage demands of animals

4) Calculate stocking rate

Know what the proper use factor is and how it may differ across systems and potential ecological

reasons how we apply the proper use factor to get from total biomass supply to usable supply

Proper use factor = set stocking rate well below carrying capacity and total forage availability. Based on maintaining sufficient plant residue for plant health/regrowth, wild forage and habitat, and erosion prevention

Understand why and how we may adjust for accessibility across the primary reasons we often

consider

We adjust for accessibility to accurately estimate usable forage and prevent localized overgrazing by accounting for new terrain, water, and vegetation that limit animal movement

Why? Could be for lots of different reasons, but distance to water, slope and topography, or vegetation density or physical barriers

Know how to calculate the forage demand for animals.

o What is the equation used with its different components.

o How does AUM factor in to this step?

Determine usable forage/biomass supply → weight of biomass/area x total area = total biomass supply

Convert total forage/biomass to total forage available → weight of biomass/acre x proper use percentage x area = usable forage supply

An example – You manage a 1,200 acre ranch and the average

production is 500 lbs/acre. The ranch is located in a sagebrush

steppe plant community and has a proper use factor of up to

30% of the annual forage.

1,200 acre ranch x 500 lb/ac = 600,000 lbs of biomass x 0.30 = 180,000 lbs useable forage.

AUM = each AU = 1,000 lbs x 2.5% = 25 lbs/day

AUM = 25 lbs x 30 days = 750 lbs

Know how to calculate stocking rate and the different components that go into it.

Example: How many cows should you have in your

base herd if your usable forage is 180,000 lbs/pasture

and the forage demand of each cow (AU) is 2,250 lbs?

Total land area (acres) / total animal units (AU) x grazing period (months)

180,000 lbs supply / 2,250 lbs demand = 80 cows

Understand what happens to animal production, and potential reasons why, when we increase our

stocking rates

Increasing stocking rates intially increaes total production per acre but eventually causes individual animal behavior and total yield to decline if pushed too high

This is because of less forage selection and lower forage quality

Identify how environmental variability may influence stocking rates and potential reasons why/how

we may account for this

Environmental variability (like rainfall or drought) directly changes how much forage (plant growth) a rangeland produces from year to year which can affect forage fluctuations, drought stress and overgrazing risks. We account for this by being flexible (no more than 60% of herd in breeding stock) and constant (herd size that could be sustained if rainfall was 25% below average)

You have a 5,000 acre cattle (i.e., 1 cow = 1 AU) ranch in a shortgrass prairie (proper use

is 40-50%) where the total production (on average) is 900 lbs/acre and you have a 90 day

active grazing season.

▪ What is your usable forage supply/year?

▪ What is your forage demand for each cow?

▪ With an AUM of 750 lbs how many AUMs are there in this ranch?

▪ How many cows is the appropriate stocking rate for this ranch?

Usable forage supply per year: 5,000 acres x 900 lbs/acre = 4,500,000 THEN put this into proper use which would be 4,500,000 x .40 = 1,800,000

Forage demand for each cow = 90 days / 30 days/month = 3 months. 750 lbs/month x 3 months = 2,250 lbs per cow

Total AUMs = 1,800,000 lbs / 750 lbs = 2,400 AUM’s

Appropriate stocking rate = 2,400 AUMs / 3 months = 800 cows

Understand what the primary terms of grazing methods are and their definitions as discussed in

class

Grazing system = a planned effort guide grazing timelines and if/how to leave areas unused

Grazing period = season, timed period, or number of days when a pasture/location is grazed

Know the difference between deferment and rest

Deferment is the delay of livestock grazing on a specific area until (typically) seed is set and matured

Rest is the complete absence of livestock grazing on a pasture for an uninterrupted and extended timeframe

Be able to describe the principles of grazing management

Balance forage and supply and demand, provide effective rest periods, avoid sensitive time periods, and manage livestock distributions

Continuous grazing definition and pros and cons

Grazing the whole area for the entire grazing season.

• PROS = simple/low input, animals get maximum choice

• CONS = plant species and areas of high preference are excessively used and can become degraded

Deferred rotation grazing system pros and cons -

Do not graze at least one pasture until after it has set seed (defer) and across years, deferment is rotated among all the pastures

• PROS = Pastures occasionally not grazed when they are most sensitive to grazing

• CONS = Can reduce animal performance a little bit bc animal opportunity to chose among plants and places is restricted, and requires more fencing and management

Rest rotation grazing system pros and cons -

Do not graze at least one pasture for a whole year (rest). In subsequent years, change the pasture rested so rest is rotated among all the pastures

• PROS = Pastures all allowed to be rested and set seed every few years

• CONS = can reduce animal perfomance bc higher stocking rate is inc. on grazed pastures, and pastures not recently grazed have dormant stems mixed with green growth

Short-duration grazing method pros and cons -

Each pasture in the unit is grazed for a short time and animals are rotated through all available pastures so that each pasture is grazed at least two times every year.

• PROS = short duration allows for high stocking rates, forage quality can be higher, all plants are often grazed

• CONS = plants never get rest or deferement, animal perfomance is usually low

Seasonal suitability grazing methods pros and cons -

Moving livestock to different areas of range depending on growth patterns of different vegetation types (i.e following the green)

• PROS = animals have green forage most of the year, plants mostly grazed in earlier seasons before seed set

• CONS = high management/herding input, summer range may not get deferment