Pasture Plant Selection

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Pasture Plant Selection Grazing Management

• T.C. GriggsDept. Plants, Soils, Biometeorology

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Environment site conditions
Availability of soil surveys http//soils.usda.go
v
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NRCS, Bozeman, MT
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Alfalfa,white clover, red clover
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Adapted pasture species

• -- Grasses
• Orchardgrass
• Tall fescue
• Bromegrasses
• Ryegrasses
• Wet meadowland grasses
• Kentucky bluegrass
• Wheatgrasses
• Wildryes

• -- Legumes
• White clover
• Red clover
• Alfalfa
• Birdsfoot trefoil (NB)
• Cicer milkvetch (NB)
• Sainfoin (NB)
• Alsike clover
• Strawberry clover

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Wet meadowland grasses

• Timothy
• Reed canarygrass
• Creeping foxtail
• Meadow foxtail

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Basic grasses for Utah pastures

• Irrigated Tall fescue (endophyte-free) Meadow
  brome Orchardgrass
• Dryland Smooth bromegrass Intermediate/pubescen
  t wheatgrass Thickspike/streambank
  wheatgrass Crested or Siberian
  wheatgrass Russian wildrye

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Species with more defoliation tolerance/rapid
recovery

• Orchardgrass
• Tall fescue
• Meadow brome
• Perennial Italian ryegrasses
• Kentucky bluegrass
• Creeping meadow foxtails
• Crested Siberian wheatgrasses
• White clover
• Red clover

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Species with less defoliation tolerance/slower
recovery

• Smooth brome
• Timothy
• Reed canarygrass
• Intermediate pubescent wheatgrasses
• Quackgrass
• Bluebunch wheatgrass
• Warm-season perennial grasses
• Alfalfa
• Birdsfoot trefoil

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Forage plant information resources

• Comparative Characteristics of Forage Species in
  Montanahttp//animalrangeextension.montana.edu/Fo
  rage/forage.htm
• Plant Guides Fact Sheets in USDA NRCS National
  PLANTS databasehttp//plants.usda.gov/index.html
  
• Intermountain Planting Guide. USU Extension
  Publication AG 510.

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How many grasses can remain productive compete
with weeds when grazed this closely?
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Pasture plant requirements

• Green leaf area for sunlight capture, or energy
  reserves to support regrowth
• In grasses, energy reserves are above ground in
  stubble
• Maintain stubble through winter for survival
  spring recovery
• Roots require energy from shoots in order to
  absorb water nutrients to potential

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Vegetative shoot (where is the apicalmeristem?)
New tiller (shoot) stack of phytomers from a bud
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Reproductive shoot Shift in status of shoot
apex Internode elongation creates true stem
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Manage reserves or retain some leaf area
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Orchardgrass, 30 hr
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Timothy, 10 days
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Residual leaf area growing points How much
height or pasture mass to leave?
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Impact of defoliation on root depth function
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Targets monitoring

• Animal performance
• Herbage mass maturity stage
• Amounts to graze, stockpile, or conserve
• Pasture growth rate
• Residual leaf area or stubble
• Soil water nutrient status
• Weeds
• Market conditions

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Seasonal carrying capacity
Annual forage prod.
Seasonal utilization level
x
Length of grazing season
Average daily intake
x
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Grazing systems

• Continuous stocking livestock have access to
  entire pasture all of the time. Potentially
  higher individual animal performance.
• Rotational stocking livestock are moved through
  a series of subdivisions (paddocks) which are
  grazed rested. Potentially higher carrying
  capacity.

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Rotational stocking dry lot
NRCS, Bozeman, MT
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General guidelines

• Initiate grazing when plants are 6-10 in. tall
• Limit grazing in a paddock to no more than 7 days
• Terminate grazing when stubble is 3-4 in. tall
• Allow at least 14-28 days regrowth