Fact Sheet No. 19: Riparian Pastures

Background

When the protection of rangeland riparian area is mentioned to ranchers, they often fear the worst and think of total livestock exclusion with fences. The following paper explains an option that in many cases will protect the riparian habitat while also improving livestock production.

Introduction

Range managers have increased their attention to riparian values in recent years. Areas once considered sacrifice areas are now considered critical for grazing management. This causes a problem in many pastures because cattle tend to concentrate in or near riparian areas, much upland forage may no longer be grazed.

Management practices can be applied to accomplish practical livestock production and proper management of upland and riparian areas. These include:

• implementing grazing systems,
• developing hillside water,
• improving nonriparian grazing,
• and building riparian pastures.

Each practice is most appropriate with only certain conditions.

Optimum Settings for Riparian Areas

Putting in riparian pastures is most efficient where existing pastures are large and cannot be managed for both upland and riparian objectives. These pastures generally include substantial amounts of upland and riparian forage. Commonly, upland forage is not grazed until after heavy use in riparian areas, and rotation grazing or range improvements will not resolve livestock distribution problems.

Concentration Of Cattle

Cattle tend to concentrate in a riparian area if

• water is not well distributed,
• the land near riparian water is steep or rocky ( especially if all the water is riparian,
• salt is placed in or near riparian areas,
• the weather is hot and riparian shade is available,
• nonriparian forage is less palatable than riparian forage,
• the herd is composed of cows with calves as opposed to yearlings,
• individual animals develop behavior patterns that favor riparian areas,
• animal distribution is not maintained by herding,
• and/or the grazing season is long.

Seaonal Differences

The effects of livestock grazing vary by season. In spring, upland forage is palatable and water more available throughout large pastures. This reduces riparian use. Cattle using riparian areas in spring can cause physical damage to stream banks and meadows. Soil compaction can also be an important problem in moist (but not saturated) loamy or clay soils.

Degraded and Unhealthy Riparian Areas
Degraded Riparian Area Pastures	Healthy Riparian Area Pastures
Lowered water table	Higher water table
Poor water storage with downstream floods and reduced summer flows.	Increased on site flooding, infiltration downstream summer flows.
Low vegetation productivity	Higher vegetation productivity
Little shade-warm water	Good shade-cool water
Poor fish habitat-poor water quality	Good fish habitat-good water quality
Low wildlife habitat diversity	High wildlife habitat diversity
Little vegetation to protect and stabilize banks	Vegetation, including roots and debris, protects and stabilizes banks

Cattle use of riparian areas generally increases as the summer progresses. It reaches a peak during periods of prolonged drought or intence heat. In late summer forage prferance switches to include more shrubs this is the time associated with most willow, asen, or cottonwood grazing. When fall rains moisen dry forage and creates frost pockets in riparian areas cattle again disperse.

Fence Construction

Riparian pastures are designed to be grazed although some need a few years of recovery first. Riparian pastures are generally much larger than exclosures. Normally their fence is built far enough away from the stream and riparian vegitation that the pasture includes upland. In fact, if there is not enough upland range included in the pasture, the upland may be overused.

The cost and amount of fence required for riparian pastures may not greatly exceed that needed for riparian exclosures. Side-fence legths can actually be shorter because the fence can be straighter. A riparian exclosure fence might need to be stronger and need more maintenance because it is within or close to the riparian area.

The top wire on both riparian pastures and riparian exclosures should be smooth (not barbed) because riparian areas provide big-game habitat and water for surrounding upland, big-game habitat. Riparian areas in antelope habitat should also have a smooth bottom wire that is no less than 16 inches off the ground. Deer generally go over fences and antelope go under.

Riparian Objectives

Writting good, reachable ojectives for riparian values is perhaps the most technicial and important part of riparian management. When setting riparian objectives the manager should:

• use stream and vegetation or soil riparian classification methods to identify similar riparian settings and then compare areas grazed differently
• or identify current problems that are obviously caused by livestock and then seek to eliminate at least some of the direct impact.

On streams that have already cut down to base level or have well-armored beds, manage for the recovery of riparian vegitation so that steep or overhanding stream banks can form and endure. These provide deep, cool pools, shade and shelter for fish. Broad, shallow streams may become so warm that cold water fish such as trout, cannot survive.

Streams that are not well-armored with rocks may depend on riparian vegetation to stabilize stream meanders. On these streams the most important objective is preventing the stream from straightening and then downcutting, causing a gully.

Management of Pastures For Riparian Objectives

How to manage riparian pastures depends largely on the vegetation needed for stabbilizing the stream bank or providing other riparian values. Steep streams typically need willows or trees with strong root systems. Flat streams can maintain stable banks with strongly rooted grasses, rushes, or sedges. Streams controlled by large cobbles and boulders don't need vegetation for bank stability. The vegetation may be important however, for wildlife or livestock forage or cover and beauty. Some streams are naturally unstable. Their confinement and high gradient generate tremendous energy during high water and vegetation has little or no effect on stream form unless it becomes especially dence and well rooted.

Shrub Lined Streams

Streams that depend on shrubs or trees can be severely imacted by heavy late-summer, fall, or winter grazing, or by frequent sheep grazing. They should be grazed in a rotation of spring and early summer use. A rest rotation or deferred rotation system that includes prolonged or intensive periods of late-season use should be avoided. Two years of rest, or grazing during non critical season, cannot make up for a grazing impact that removes three years growth on woody species.

Grass, Sedge and Rush-Lined Streams

The effects of improper grazing may show up quicker and be difficult to reverse along streams that depend on grasses, sedges, and rushes. On these streams rotation grazing systems that include late-season use sometimes work well when overall livestock distribution favors nonriparian areas and when sediment can be trapped in last year's regrowth and stabilized by new growth.

Recovering Gullies

Sediment can build stream banks and raise the bottom of old, wide gullies. Some gullies fill and widen sufficiently to allow the stream to meander across a broad floodplain. This greatly reduces the force of flood water and allows it to soak into the soil. Stable banks along low-gradient meandering streams form deep, narrow channels that can provide good fish habitat while the floodplain provides water storage and flood control.

Midsummer Use

Midsummer (late spring in coastal California) use for a short time rotated between years offers several advantages. By midsummer (late spring),

• stream banks are generally firm,
• there is still sufficient soil moisture and warmth for riparian vegetation to regrow before winter,
• sediments in spring flood waters have been trapped by last year's standing dead regrowth,
• herbaceous species may still be green and forage preference has not yet shifted to woody species,
• and livestock can most benefit from green feed after range has matured.

The reason for a short season is to minimize grazing of regrowth and to achieve, but not exceed, proper use levels. Use at this time can be heavy if the season is very short and there is moisture available for regrowth. Use can be prolonged if utilization levels are conservative.

Location and Size

Ideally, riparian pastures should be located and designed to fit the livestock production operation. They should be used for bulling, weaning, pregnancy checking, shipping, gathering, or grazing pastures. Labor can be saves by locating them where cattle will automatically use them in the normal sequence of rotation. Topography and cattle numbers have a great influence on size and location. In some settings a series of riparian pastures can be set up for sequential or rotation grazing. Riparian pasture fences may also divide large pastures, allowing the implementation of a large scale rotation grazing system.

By Dr. Sherman Swanson, Riparian Scientist and Extension Range Specialist, Environmental and Resource Science Department, University of Nevada - Reno, Nevada

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prepared and edited by John Harper, Ken Tate and Mel George

Fact Sheet No. 23: Stream/Watercourse Site Evaluation^1

RANCH NAME_______________________________________	QUARTER SECTION_________________
STREAM NAME OR DESCRIPTION_________________________________________________________
LOCATION/WITNESS POINTS______________________________________________________________
PHOTO STATION: _____ Perpendicular	_____ Oblique to stream
STREAM TYPE: _____ Perennial/year around	_____ Intermittent/seasonal

CURRENT PRECIPITATION YEAR: _____ Wet _____ Normal _____ Dry

CHANNEL TYPE/PATTERN:

a. _____ Deeply entrenched _____ Moderately entrenched _____ Slightly entrenched

b. _____ Well confined _____ Moderately confined _____ Poor/no confinement

c. _____ Straight/slightly sinuous _____ Meandering or braided

STREAM GRADIENT: _____ Steep (over 10%) _____ Moderate (4-10%) _____ Gentle (<4%)

STREAM WIDTH/DEPTH RATIO: __________

PREDOMINANT STREAMBANK CONDITIONS (% stability):

_____	Stable (<5% degradation): armored with rock/vegetation/roots/overhang/no headcuts/little impact of high flow or access traffic.
_____	Some instability (5-25% degradation): occasional sloughing/erosion/exposure to bare soil/strata/ evidence of travel impacts.
_____	Significant instability (>25% degradation): frequent sloughing/exposed soil/headcuts/chiselling compaction by vehicles, livestock, or people.

VEGETATION:

_____	Typical riparian perennial water-loving species dominating; bottomland/alluvial or upland perennial watercourse.
_____	Riparian herbaceous and woody species infrequent; upland foothill intermittent watercourse.
_____	Principal watercourse/stream flood plain cover:

	0-25%	25-50%	50-75%	75-100%
Trees - canopy	_______	_______	_______	_______
Shrubs - canopy	_______	_______	_______	_______
Herbaceous - canopy	_______	_______	_______	_______

Major Species _______________________________________________________________________

Watercourse residual/mulch/plant cover filter strip function: _____ High _____ Moderate _____ Low

Utilization of riparian vegetation: _____ None _____ Light _____ Moderate _____ Heavy

Grazing or browsing by: _____ Livestock or _____ Wildlife

WATER TURBIDITY/CONDITION: (period since last storm: _____ <2 days _____>2 days)

_____	Clear or very slightly turbid/muddy: bottom objects clearly visible to depths of up to 3 feet.
_____	Considerable/moderate turbidity: objects visible to only about 1½ to 3 feet depth.
_____	Very turbid/muddy/sediment-loaded: objects not visible at more that ½ to 1½ feet depth.

WATER TEMPERATURE: _____ Cold (<50%) _____ Cool (50 to 70%) _____ Warm (>70%)

CHANNEL BOTTOM CONDITION:

_____	No evidence of recent bed material movement/deltas/sediment bars/scouring; pools free from deposition.
_____	Some or few fine gravel/sand/silt bars/deltas present and without vegetation cover.
_____	Abundant evidence of erosion and/or deposition; sediment bars/deltas present and unvegetated; pools silted.

_____ % bedrock _____% gravel _____% sediment

AQUATIC BIOLOGY (Riparian, perennial streams, or pools)

	Abundant/Diverse	Some/Few	None
Fish	_______________	_________	______
Amphibians	_______________	_________	______
Insects	_______________	_________	______
Emergent Plants	_______________	_________	______
Algae	_______________	_________	______

ADDITIONAL COMMENTS:	________________________________________________________________
___________________________________________________________________________________________
___________________________________________________________________________________________
___________________________________________________________________________________________

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MANAGEMENT ACTIONS

_____	Changes in management are not justified.
_____	Further examination of watershed is needed.
_____	Request visitations and advice by resource specialist.
_____	Consider prompt changes in kind, degree, time of land use.
_____	Develop water quality management plan or element of ranch management plan.

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prepared by John Stechman, UC Cooperative Extension, USDA Morro Bay Hydrologic Unit Area Project, and Jim Clawson, Extension Range Specialist, Agronomy & Range Science, University of California, Davis.

¹To be used with individual streams or stream reaches.