Transcript Administrative Update - Colorado State University

Developed by:
Hud Minshew, Oregon State University Extension Service
Susan Donaldson, University of Nevada Cooperative
Extension
UNCE, Reno, Nev.
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Sources of irrigation water:
◦ surface versus well water
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Matching available water to:
◦ soils and plants
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Determining when it’s time to irrigate
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Irrigation systems
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Do you have a water right?
Where will your water come
from?
When or how often will you
get your water?
www.farmphoto.com
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UNCE, Reno, Nev.
Does local law allow use
of domestic well water
for pasture irrigation?
Does your well produce
enough water?
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What plants do you
want to grow?
Do you have enough
available water to
support the plants?
Are your soils
appropriate for
growing the plants
you selected?
UNCE, Reno, Nev.
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USDA
Do you want to
improve existing
pasture, or start
over?
How much time
and money do
you have?
Adapted from PNW 475 by A. Miller
Rooting Depth in Feet
Alfalfa
4’ – 6+’
A. Miller
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What is the capability class
of the soil?
What are the slopes and
aspects?
How deep is the soil?
Does it have adequate
drainage and rooting
depths?
Is compaction an issue?
USDA NRCS
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CLAY
SILT
Moderate
spread and
infiltration
SAND
Deepest
penetration
Wide, but more
shallow, infiltration
A. Miller
Soil texture
Sand
Sandy loam
Infiltration rate,
inches per hour
2-4
1-3
Silt loam, loams
0.25 – 1.5
Silty clay loams, clay
0.1 – 0.3
0.4
Water Content (% volume)
0.35
Field Capacity
0.3
0.25
Available Water
0.2
0.15
Wilting Point
0.1
Unavailable Water
0.05
0
Sand
Sandy
Loam
Loam
Silt
Loam
Clay
Loam
Silty
Clay
Clay
Finer Texture
OSU Extension Service
A. Miller
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Does your water right
supply enough water?
Will you have water during
dry years?
Do you need to reduce
your irrigated acreage to
match your water supply?
Can you use your water
more efficiently?
UNCE, Reno, Nev.
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Rule of thumb:
◦ When the amount of water-holding capacity is
at 50%
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If your plants are showing signs of stress,
irrigation is overdue
◦ Look for wilting or grasses that don’t spring
back up when stepped on
USDA NRCS
Clay, clay loam or
silty clay loam at
25 to 50% moisture
Clay, clay loam or
silty clay loam at
50 to 75% moisture
Irrigation is overdue.
Will need to irrigate
soon.
USDA NRCS
Sandy loam or fine
sandy loam at
25 to 50% moisture
Irrigation is overdue.
Sandy loam or fine sandy
loam at 50 to 75%
moisture
Will need to irrigate
soon.
UNCE, Reno, Nev.
Bureau of Reclamation
COAgMet - local weather station info and daily
ET rates. A great resource to know when to
irrigate based on weather and EC
http://www.coagmet.colostate.edu/
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Does your irrigation water contain trace
elements that may affect plant growth?
Is the water salty?
What are upstream users doing that might
affect your water quality?
USDA-NRCS
Surface
Sprinkle
USDA NRCS
Micro-irrigation
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Your flexibility may be limited with an
existing system, but costs will be lower
Starting over allows you to carefully
match soils, plants and water availability
with irrigation systems, but can be
costly
New irrigation systems may save time,
money or water
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None – select an irrigation system that does
not require power
Electricity from an existing power line
An internal combustion engine
Solar power
◦This one pictured is
not able to support a
pressurized irrigation
system. Can handle a
stock tank though!
USDA NRCS
UNCE, Reno, Nev.
NRCS Irrigation Page
UNCE, Reno, Nev.
UNCE, Reno, Nev.
USDA NRCS
USDA NRCS
UNCE, Reno, Nev.
CSU Cooperative Extension
USDA NRCS
USDA NRCS
A. Miller
USDA NRCS
UNCE, Reno, Nev.
USDA NRCS
USDA ERS
Water
delivery is
controlled
by a valve.
ERS USDA
Univ. of Idaho Extension
B. Hamblen, CSU Extension
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Do you have a legal right to reuse tailwater?
How will you capture and store the water for
subsequent use?
Maximizes the use of surface irrigation water.
Who will do it, and
what will it cost?
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Dredging and re-digging
Weed and vegetation
control
Open/close gates
Adjusting siphon tubes
Permission and access
issues
OSU Extension Service
UNCE, Reno, Nev.
USDA NRCS
USDA NRCS Mont.
USGS
USDA NRCS
www.clemson.edu
USDA NRCS
USDA NRCS
www.k-linena.com
kygraziers.com
ERS USDA
USDA NRCS
USDA NRCS
USDA NRCS
UNCE, Reno, Nev.
Univ. of Idaho Extension
USDA SCS
USDA NRCS
USDA ARS
UNCE, Reno, Nev.
Checking your system:
Does it apply water uniformly?
UNCE, Reno, Nev.
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Monitor your system during irrigation
and check for leaks or clogging of
screens
Look for areas that remain too wet or
too dry and adjust your irrigation
system
Check sprinkler system pressures and
nozzles to make sure they are
adequate
Consider system upgrades
OSU Extension Service
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Know your sources of irrigation
water
Know your soil type
Monitor soil moisture
Improve efficiency of your
delivery system when possible
 Adjust
rate of water application
to avoid runoff
 Know your labor availability
 Match your goals for your land to
the irrigation system you select
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Practice the Look-and-feel Method for
determining irrigation.
Inventory your irrigation system, both
existing and proposed, using the
Irrigation Checklist for Landowners
Activity Sheet.
Check the uniformity of your sprinkler
system, using any of the methods
discussed in this lesson.