Introduction
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A low-energy, precision
watering device irrigates an alfalfa field in Newberry Springs,
Calif., part of a SARE grant project teaching farmers how to
use soil moisture sensors to conserve water.
Photo by Ron Daines |
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On a steep farm hillside where his parents had previously grown
hay, Tim Gieseke planted black walnut trees. While he expects to
harvest valuable timber in two decades or more, Gieseke grows hay
between the rows and will harvest walnuts and graze a flock of sheep
in the grove. The enterprises, which make great use of a 15-percent
slope that otherwise would have to be left in grass or forage, also
feature an important,water-saving innovation to capture rainfall.
Gieseke designed his agroforestry system to maximize water availability.
Walnut trees need 35 inches of water a year to thrive, but Gieseke’s
farm in southern Minnesota averages 30 inches of precipitation annually.
To make up the difference, Gieseke, with help from a Sustainable
Agriculture Research and Education (SARE) farmer grant, constructed
a contour system featuring irrigation holes that trap hillside runoff
and convey it to the tree roots. (See profile)
“The hillside obviously sheds water, and quickly in the
spring when we have snow melt,” said Gieseke, who farms 50
acres. “We wanted to capture that runoff.”
He planted tree seedlings in rows 20 feet apart, created earthen
curbs on the contour and augured 9-inch-wide, 30-inch-deep holes
between every other tree. The swiss-cheese infiltration system absorbs
water from even torrential downpours with minimal runoff.
“If we get a sudden rain, we probably get all of the moisture
into the ground, whereas without it, 90 percent of that would run
down the hill,” Gieseke said. In the first three seasons,
he has not irrigated the walnut saplings.
All over the country, and especially in the desert Southwest and
semi-arid Plains, farmers and ranchers worry about water. Agriculture
accounts for about 85 percent of U.S. water consumption, a reality
that contributes to declining ground and surface water quantity
and quality. Severe long-term droughts and explosive population
growth in dry, previously rural areas compound the problem.
In response, farmers, ranchers and agricultural researchers are
designing innovative runoff collection systems like Gieseke’s,
managing soil to improve infiltration, and selecting drought-tolerant
crops and native forages that grow well with less water.
“The hard truth is that we’re drawing down the aquifer,”
said Vivien Allen, a Texas Tech University researcher who received
two SARE grants to study cotton systems that make better use of
water. “When I came here in 1995, the clear message was that
everything pivots around water.”
Access to water has been controversial since settlers migrated
west. Today, throughout the West, urban and suburban dwellers compete
with one other and with farmers and ranchers over Colorado River
withdrawals. Even in the Northeast, farmers face water challenges
with annual, short-term droughts.
“Most field crop farmers will experience drought in most
years,” said Harold van Es, a Cornell crop and soil science
professor, who is partnering on a SARE grant examining strategies
to improve soil quality, including its ability to hold water. “They
are absolutely concerned about water.”
Yet, you can create systems that require less water or make better
use of what’s available via aquifers, streams, rivers, ponds
or precipitation. This bulletin from the Sustainable Agriculture
Network is written for producers and agricultural educators who
want to consider new approaches to agricultural water use. It showcases
innovative research, much of it funded by the Sustainable Agriculture
Research and Education (SARE) program, that identifies a range of
promising water conservation options.
The bulletin is organized around the following broad tenets:
Managing
soil. Applying practices that build soil quality, resulting in
a porous, well-structured soil that allows water to infiltrate
and holds it there for use by plants. (Part
1)
Managing
plants and livestock. Selecting plants, such as drought-tolerant
species and native varieties that maximize water availability
in crop rotations or pastures. (Part 2)
Managing
water. Treating water like a precious resource, capturing, conserving
and recycling it among farming enterprises. (Part
3)
For tips on applying some of these strategies on your farm or
ranch, or more in-depth sources of information, consult the "What
You Can Do" boxes at the end of each section and Resources.
Soil Management
| Plant Management | Water
Management
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