12/20

Opportunities in Agriculture

Smart Water Use on Your Farm or Ranch

Idaho farmer Pat Purdy is able to deliver more water to the soil with a low-elevation spray application system (the 

pivot span on the right) than a standard spray system (the pivot span on the left) because of reduced wind drift. His 

adoption of this technology, along with soil health practices, has improved water management on his farm. Photo by Pat Purdy

WHEN PAT PURDY RETURNED HOME TO JOIN HIS FATHER

Nick at Picabo Livestock Company near Picabo, Idaho, 

in 2008, his desire was to beef up the farm’s environmental efforts with a fresh perspective. The farm has 

been in the family since the 1880s with the goal of living 

in harmony with Silver Creek, which runs alongside the 

property. Silver Creek is a major trout stream.

And while Silver Creek is close by, the farm itself is 

on a flat, arid span amid a higher mountain altitude. 

That makes irrigation mandatory for the malt barley 

grown on contract for Anheuser-Busch and Coors. The 

Purdys also raise alfalfa hay and mustard seed, and 

have a cow-calf enterprise.

“We get 12–14 inches per year of precipitation from 

mostly snowpack and little to no summer rain,” Purdy 

says. “Water availability is always a concern, so we are 

efficient in how we use it.”

In 2017, Purdy used a SARE grant to see if he 

could save water using a low-elevation spray application system (LESA) with cover crops, no-till and 

CONTENTS

INTRODUCTION 1

PART ONE: 

SOIL MANAGEMENT 3

Cover Crops 4

Compost and 

Amendments 8

Conservation Tillage 8

PART TWO: 

PLANT MANAGEMENT 9

Crop Rotation 9

Water-Conserving Plants 9

Rangeland Drought 

Management 11

PART THREE: 

WATER MANAGEMENT 14

Irrigation Systems 14

Types Of Irrigation 

Systems 14

Drain Water 

Management 17

Managing Salinity 18

Smart Irrigation 19

RESOURCES 20

managed intensive grazing. The plan was to follow 

intensive grazing of cover crops with a malt barley crop the 

next season. He hoped to get a positive income stream the 

first year from cattle grazing followed by improved barley 

yields in year two.

LESA systems are attractive options compared to 

traditional center pivot irrigation because, with low-to-theground sprinkler heads, water is applied at lower pressures, 

which reduces pump power consumption and increases efficiencies. (The exact potential of a LESA system to improve 

efficiency will depend on the region, soil type, crops being 

grown and management practices.)

According to soil moisture sensors, the LESA system 

delivered 3.1 inches of additional water into the soil over 

the course of the season compared to using the conventional center pivot with no cover crops. In addition, soil 

water infiltration reached 32 inches under the LESA 

system with cover crops versus 12 inches under the center 

pivot control. The extra water represented a chance to save 

15–20 percent of pumped water.

Also available at 

www.sare.org/water-bulletin, 

or order a free hard copy 

at (301) 779-1007.
Water conservation was not the only benefit. Purdy wanted to reduce wind erosion 

and enhance wildlife habitat by eliminating the bare soil that comes with fall tillage and 

winter fallow, so he planted cover crops. He no-till seeded a cool-season mix of forage 

barley, oats, peas, common vetch and purple top turnips in the spring. Cattle grazed the 

area separated into paddocks, moving once or twice a day. Following the first grazing of 

the cool-season mix, Purdy planted a warm-season mix for late summer forage. He was 

able to get four grazing cycles per season. 

“Regenerative agriculture will benefit any farm,” states Purdy. “We now have an 

organic matter layer on the soil surface that absorbs moisture and reduces puddling. We 

also reduced fuel use and wear and tear on our equipment. We saw a 10–15 bushel per 

acre bump in barley yields that was a direct result of the soil health improvements from 

intensive grazing the prior year. To me, that showed us the effort was all worthwhile.”

A Systems Approach to Water Management

Water is fundamental to food production. In fact, agriculture accounts for 85 percent of 

U.S water consumption, according to the USDA Economic Research Service. Yet, farmers 

nationwide face water-related challenges, whether it’s too little, too much or both. And 

some practices have contributed to declining water quantity and quality.

For example, in the West, urban and suburban communities compete with each other 

and with farmers and ranchers over water withdrawals from the Colorado River. In the 

Northeast, farmers face water challenges with annual, short-term droughts. And coastal 

farmers deal with increasingly more dramatic wet and dry spells, as well as saltwater 

intrusion that requires unique management strategies.

Many farmers around the country like Purdy are using a whole-farm approach to 

tackle their water problems. Rather than relying on changes to individual areas of their 

operation, they are adopting farm-wide practices that build soil, improve crop and 

livestock management, and efficiently use water across the farm. Farmers are simultaneously changing up crop rotations, incorporating cover crops, reducing tillage, integrating 

crops and livestock where feasible, improving their irrigation systems, and more.

This bulletin 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 that are often used in conjunction to improve overall water management:

» Part 1: Soil Management. Apply practices that build soil health, which results 

in a porous, well-structured soil that allows water to infiltrate and holds it there 

for plants to use.

» Part 2: Plant and Livestock Management. Select plants, such as droughttolerant species and native varieties, that maximize water availability in crop 

rotations or pastures; practice other rangeland management strategies.

» Part 3: Water Management. Improve the efficiency of irrigation systems; 

refine application schedules and volumes to meet crop needs without 

over-watering.

2 www.SARE.org

Water Management in a Changing Climate

The importance of sustainable water management 

will continue to grow as the impact of climate 

change intensifies. Temperature and moisture 

extremes are projected to increase in frequency 

and intensity over the next 30 years throughout the 

country. Heavy rainfall interferes with field operations, causes labor issues, degrades soil health, 

threatens crops and livestock, and damages infrastructure. Drought is challenging even with 

irrigation, if access to water becomes limited.

As one example, University of Vermont graduate 

student Alissa White surveyed vegetable and berry 

farmers in New England to identify the adaptive 

strategies they’re beginning to use to meet climaterelated challenges. Her project, funded through a 

SARE grant in 2017, found that growers were most 

concerned about projected increases in heavy 

precipitation and drought.

To adapt to these challenges, White concluded, 

farmers should start by using a whole-systems 

perspective for farm planning, and they need to 

understand the flow of water on their land. 

Strategies that farmers are using to cope with too 

much precipitation include the use of raised beds, 

investments in stormwater management, adjusted 

crop locations based on site and soil characteristics, 

new high tunnels, perennial plants and reduced 

tillage. Management strategies for drought include 

water harvesting, efficient irrigation systems, mulch, 

reduced tillage, cover crops and crop planning.

The strategies for managing water outlined in this 

bulletin are part of a holistic approach to conserving water and reducing the climate risk your farm or 

ranch faces. Learn more about how sustainable 

farming and ranching practices provide climate risk 

management in SARE’s bulletin Cultivating Climate 

Resilience on Farms and Ranches (www.sare.org/

climate-resilience).

Photo by Lance Cheung, USDA
www.SARE.org 3

Adding organic matter 

to the soil, reducing 

disturbance and 

maximizing living roots 

(a rye cover crop is 

pictured here) are key 

strategies for improving 

water management. 

Photo by Edwin Remsberg

Part One 

Soil Management

THINK OF THE SOIL AS A SPONGE: IT ABSORBS AND HOLDS

water, and it reaches a point where it’s full and cannot 

hold any more. Unlike a real sponge, though, you can 

change the amount of water that soil can hold through the 

way you manage your soil. However, you are somewhat 

limited by your soil’s texture. Keep in mind, finer soils that 

have a high percentage of silt and clay particles tend to 

hold more water than coarse, sandy soils.

Otherwise, practices that add organic matter and 

improve soil structure, such as adding compost or cover 

cropping, will increase water infiltration and waterholding 

capacity while decreasing runoff and erosion. Such soils 

are porous and allow water to enter easily, rather than 

running off to streams and rivers. With poor tilth, soil 

aggregates break down, compaction increases, and 

aeration and infiltration drop.

Most soil-improving strategies work slowly over several 

years. In contrast, management practices that degrade soil 

are often immediately apparent. Working soil when it is 

too wet will quickly compact it and degrade its structure. 

Degraded soils do not absorb precipitation as quickly or 

hold as much, which leads to increased ponding and runoff 

of excess water when it rains.

Organic matter also plays a vital role in soil health and 

water availability. Organic materials like cover crop 

FIGURE 1. RAINDROP ENERGY AND SOIL MOVEMENT

residue or straw mulch applied to soils and maintained on 

the soil surface protect the soil from erosion (Figure 1). 

Vegetative cover deflects rain drops, while living roots and 

the exudates they produce hold soil together. Additionally, 

surface residues and mulches reduce evaporation and 

smother weeds, so plants have more water.

During a rainfall 

millions of drops fall at 

speeds up to 30 feet 

per second. Without 

raindrops, little soil 

erosion would be 

caused by water.

Raindrops explode like 

tiny bombs, splashing 

water and soil particles as 

high as 3 feet and as far 

to the side as 5 feet, and 

breaking soil aggregates 

where the soil surface is 

not protected.

Small aggregates and 

soil particles can be 

carried down slopes 

and off fields where the 

soil surface is not 

protected. Crop residue 

on the surface can 

prevent most soil loss.

Falling on water Falling on soil With surface residue

Illustration by Vic Kulihin
4 www.SARE.org

As organic matter increases, soil particles clump 

together and form aggregates. The spaces between aggregates are called macropores and are important for soil 

water dynamics. These larger pores contain open spaces 

that facilitate drainage and aeration. Smaller micropores 

fill with water and contribute to the total waterholding 

capacity of the soil. Plant residues and other organic 

amendments decompose and help bind soil particles 

together.

Strategies to increase organic matter content include:

» Spreading manure or letting livestock deposit 

manure in well-managed pastures.

» Applying composts from a variety of materials 

ranging from poultry litter to leaves.

» Rotating crops and using cover crops, which 

provide nutrient-rich residue after they die.

» Reducing tillage. Plowing breaks down soil aggregation and hastens organic matter loss.

Cover Crops

Cover crops, seeded between or amid cash crops, contribute a variety of conservation benefits for water and soil. 

For water, they offer a triple bonus. A living cover crop 

traps surface water. When killed and left on the surface, 

cover crop residue bumps up water infiltration and lessens 

both erosion and evaporation. When incorporated into 

soil, residue adds organic matter that boosts infiltration to 

the root zone.

Before choosing to test any cover crop species, first 

identify your needs and consider factors like your cropping 

system, climate, tillage options, planting window, soil type 

and more. Where water conservation is the goal, adding a 

grass into the rotation, either as a hay crop or forage, can 

This multi-species cover 

crop is being grown on a 

farm in eastern Oregon 

to evaluate whether it 

can conserve moisture in 

a dryland system. Photo by 

Garrett Duyck, USDA NRCS

Rotational grazing 

increases both organic 

matter and the 

waterholding capacity of 

pastures. Photo by Lance 

Cheung, USDA
www.SARE.org 5

Profile: Wicking Hills and Cover Crop Valleys

Like many farmers in the Northeast, Louis Lego, Jr. has increasingly faced flooding 

and drought troubles while he grows certified organic fruits and vegetables at 

Elderberry Pond Country Foods in Auburn, N.Y. In 30 years of farming, Lego has 

never seen a greater climate challenge. But through trial and error, he has finally 

found an effective way to manage his soil for the extremes.

“The last three years, every spring has gotten worse with heavy rains and flooding. The water was not getting absorbed,” he states. “We have a nice loam soil, but 

the fine particles were coming to the top in our flat fields, creating a layer that 

made it difficult for water to filter down.”

As an organic farmer, Lego is required to plant cover crops every three years. But 

they were no match for the impact of heavy precipitation on the soil. Lego first 

tried adding more drainage tiles. His neighbors did as well, and the result was more 

water draining into streams and causing flooding. They expanded their pond to 

catch more water and tried hybrid mulching techniques. Neither of those strategies 

worked well either. So, Lego turned to “wicking hills,” a type of raised bed system 

that contains natural wicking/drainage materials in the form of straw or plant stalks. 

In his case, Lego used sunflower stalks.

“Wicking hills have been by far the best solution for keeping water on the farm—

higher soil moisture and no flooding. It is a natural irrigation and flood protection 

system,” he says. “But it takes some time and effort up front to put the hills in 

place. It is a multi-step, multi-year process.”

Supported by a SARE grant, Lego designed his wicking hill system for vegetable 

production, and he notes that root crops do very well in the raised rows, including 

carrots, onions, garlic and potatoes. The only equipment requirements were a 

rotary plow and a seed spreader. He planted sunflowers in the rows of hills he 

created during the first year. The leftover sunflower stalks become the wicking 

fiber for new wicked hills in subsequent years. The sunflowers also provide valueadded cut flowers and chicken feed.

The second year, the raised rows use the high-carbon sunflower residue to stabilize the hills. They also drain excess moisture when it is wet and draw up water to 

keep soils moist when it is dry, through capillary action. 

In between the hilled rows, Lego plants a cover crop of medium red clover. The 

clover absorbs excess water during storms and improves soil health. Soil quality 

tests confirm higher nutrient availability, more neutral soil pH and higher organic 

matter content. 

Lego is still evaluating the long-term results of the SARE-funded trial. For 

example, the clover cover begins to deteriorate after a couple of seasons and may 

need to be periodically reseeded.

“It is a lot of work to put the hills in, but we believe it has been worth it,” he 

affirms. “We have no weed issues, no water runoff and no replanting. Our pickers 

have better conditions standing in clover rather than in mud, and our crop yield and 

vegetable quality surpassed our expectations.”

Elderberry Pond supplies vegetables, fruits and meat to its on-farm retail store, 

farmers’ markets and its own restaurant, promoting small-scale sustainable farming 

and demonstrating the quality and nutrition of local food production. Lego also 

makes presentations to farm groups about the wicking hills system and invites visitors to the farm to see how it works first hand.

“We have converted the whole 25-acre production area to this system,” says Lego. 

“It is very sustainable, good for small farms and easy to adapt for home gardens.”

Learn more: https://projects.sare.org/sare_project/fne18-903

“Wicking hills” are a raised bed system that contains 

natural wicking or drainage materials, such as sunflower 

stalks, and acts as a natural irrigation and flood protection 

system. Raised vegetable beds are prepared (top) after 

sunflowers are grown and harvested (bottom), and cover 

crops grow between rows. Photos by Louis Lego
6 www.SARE.org

improve soil aggregation, since the complex root system of 

grasses loosens soil. 

Grasses like rye, wheat and sorghum-sudangrass 

produce biomass that, when terminated, provides soil 

coverage to reduce evaporation rates and supply organic 

matter. Tillage radish and its deep taproot are useful for 

breaking up compacted soils and improving water infiltration (Figure 2).

Learn more about selecting and managing cover crops 

in Managing Cover Crops Profitably (www.sare.org/

mccp).

The conservation benefits of cover crops usually 

translate into higher yields, cost savings or both, especially 

when water is scarce. During the severe drought of 2012, 

some Midwestern and Western farmers who had planted 

cover crops found that corn yields were an average 9.6 

percent higher than on fields where cover crops had not 

been planted. Soybean yields were 11.6 percent higher, as 

reported by farmers who participated in the six-year 

National Cover Crop Survey conducted by SARE, the 

Conservation Technology Information Center and other 

partners (view survey results at www.sare.org/covercropsurvey). Better yields were most likely due to cover crops 

providing ground cover, reducing evaporation and 

increasing available soil water for the crop.

In drought conditions, corn and soybean farmers can 

expect to recoup the cost of cover crops in a single year, 

according to an economic analysis of the National Cover 

Crop Survey found in the SARE report, Cover Crop 

Economics: Opportunities to Improve Your Bottom Line 

in Row Crops (www.sare.org/cover-crop-economics).

Depending on how many years the farmer was using cover 

crops for before the onset of a drought (from one to five 

years), they can expect an average return on corn of 

FIGURE 2. THE EFFECT OF COMPACTION ON WATER STORAGE

Left: Compacted soil had reduced pore space between soil particles, which reduced the ability of the soil to absorb moisture. This increases 

erosion and results in poor crop health. Right: A tillage radish cover crop can break up compaction and increase pore space between soil 

particles, which allows the soil to hold more water for crops to use (see the photo on this page). Illustration by Carlyn Iverson

This hole was created by 

the large taproot of a 

tillage radish cover crop. 

Photo by Edwin Remsberg

Reduced 

pore space

Soil particles

Soil 

particles

Pore space
www.SARE.org 7

Profile: Coastal Modification for No-Till Success

Mary Connor tested this 

roller crimper that has 

been modified to work 

on raised beds at her 

South Carolina farm, 

where she has to manage 

with regular periods of 

both drought and 

flooding. Photo by Mary 

Connor

In the coastal region of South Carolina where Mary 

Connor runs Three Sisters Farm with her two sisters, 

practices that improve soil health and water management are critical but complicated. Because of tropical 

weather conditions that often bring extreme rains, 

they need to grow their vegetable crops on raised 

beds on their 90-acre farm. This makes it difficult to 

practice no-till, even though conservation tillage and 

cover crops are needed both to improve organic 

matter in their sandy soils and to conserve moisture 

during periods of drought.

“Our high annual rainfalls typically occur in concentrated time intervals. We can get eight inches of rain 

over a 48-hour timeframe,” says Connor. “Raised beds 

help prevent complete water saturation of plants. But 

converting to no-till in the beds has many obstacles 

in the coastal plain.”

To begin with, most no-till equipment is not 

designed for raised beds. And sandy soils in the 

coastal plains are susceptible to losing nutrients and 

carbon in the soil structure. To enhance moisture 

retention, humus in the soil must be retained through 

something like cover crops.

With funding from a SARE grant, Connor tested a 

no-till roller-crimper that was modified to work on 

the raised beds of her Bluffton, S.C., farm. Her aim 

was to manage the impacts of frequent flooding and 

drought, as well as to enhance and improve soil 

health, using the combination of no-till, cover crops 

and tarping. Her approach to improving water 

management and soil health combined an Austrian 

winter pea cover crop with surface mulch to lower 

water loss via evapotranspiration. 

Using a roller crimper in no-till, raised-bed applications is a relatively new way to terminate cover crops. 

It is designed to kill cover crops by crimping but must 

be timed properly to prevent cover crops from 

regrowing. Once the family terminates their Austrian 

winter pea cover crop, they tarp for a month to 

ensure die down. This allows clean transplants. The 

cover crop mulch provides weed suppression and 

moisture retention for vegetable crops. 

“The water retention of our soil has noticeably 

improved since we started this process,” Connor says. 

“This is a small farm, so we do not have any water 

meters. But I can tell you from walking the farm a 

couple of times a day, there is a visual difference. You 

can feel the moisture when you handle the soil even 

during those periods when we may go two or three 

weeks without rain.”

In addition to cover crops, Connor uses tarping to 

retain soil moisture and to manage problematic, often 

herbicide-resistant, weeds 

like nutsedge. Tarps reduce 

the time spent weeding by 

hand by about 250 labor 

hours, which represents a 

savings of $4,000–$6,000. 

Additionally, she puts silage 

tarps on raised rows until 

planting, keeping topsoil in 

place and weed seeds out. 

Connor has observed higher 

yields with these tactics as 

well as reduced labor for 

weeding. 

Other soil and water 

conservation efforts include 

getting double-ground leaf 

and grass mulch from a large 

residential resort development on nearby Hilton Head 

Island, and using drip irrigation and micro-irrigation as 

needed for lettuce and 

carrots. The water comes from an onsite well.

Soils are tested every five years. Connor has been 

able to reduce fertilizer use with a documented 

increase in organic matter and Cation Exchange 

Capacity (CEC). CEC is used as a measure of soil fertility. A higher CEC reflects well-humified organic 

matter and clay minerals.

“By building organic matter, soil characteristics like 

waterholding content and water infiltration have 

improved,” states Connor. “CEC was raised to 9, 

where typically we would have only a range of 3–6 on 

most areas. That is as dramatic as if we added highquality compost to our soil.” 

Temperature variations that happen more 

frequently are another concern for the coastal farm. 

Connor has moved frost-sensitive crops like lettuce 

into the farm’s hoop house for production and has 

switched to more weather-hardy plantings outside, 

such as bok choy, spinach, broccoli, collards and 

carrots.

And while Connor says other farmers can replicate 

her work, she cautions not to expect overnight 

results. “You have to be willing to adapt to your 

conditions,” she says. “This is a unique area, so what 

works elsewhere may not work here, and what works 

here may not work in other regions.”

Learn more: https://projects.sare.org/sare_

project/fs16-288
8 www.SARE.org

$27.34–$110.45 per acre. The average return on soybeans 

is $41.69–$84.54 per acre.

In 2008, no-till farmer Keith Berns began experimenting with cover crops in dryland rotations of corn, soybeans 

and wheat on his Bladen, Neb., farm. This SARE-funded 

project revealed that some multi-species cover crop mixes 

conserved water as well as wheat stubble alone, and they 

resulted in higher yields of the following corn crop than 

stubble.

“Results of this project made us firm believers in cover 

crops,” Berns says. Today, Berns and his brother Brian 

continue using diverse cover crop species on their 2,000-

acre farm to increase organic matter and manage soil 

fertility. They also operate a thriving cover crop seed 

business. Moisture management remains both a focus and 

a challenge each spring as they make decisions about 

when to terminate cover crops and plant cash crops based 

on available moisture in the soil.

Compost and Amendments

Some farmers, particularly organic farmers, have long 

applied manure and compost to meet fertility needs. Most 

non-organic vegetable producers rely on the quicker fix of 

annual applications of commercial fertilizer. In either case, 

nutrient applications should be based on the crop’s needs 

and on results from soil testing if they are to enhance soil 

health and water management. 

Animal manures are high in important crop nutrients 

and help build and maintain soil organic matter. Analyze 

manures first to accurately determine application rates. 

Keep in mind potential limitations like pathogen contamination of crops intended for direct human consumption 

and accumulations of potentially toxic metals if application rates exceed crop needs.

Composting organic residues before applying them to 

soil can, if done correctly, eliminate plant disease 

organisms, weed seeds and many potentially noxious 

chemicals. Compost provides extra organic matter that 

improves the soil’s waterholding capacity and provides a 

slow release of nitrogen. Good composting requires 

plentiful, decomposable carbon- and nitrogen-containing 

materials, good aeration, moist conditions and enough 

pile size to allow high temperatures to develop for 

microbial activity. 

Conservation Tillage

Conservation tillage leaves at least 30 percent of the soil 

surface covered by residue after planting. No-till planters 

leave even more than that by placing seeds or transplants 

in narrow slots, the only area where farmers disturb the 

soil. No-till also consistently improves water infiltration, 

with reports of up to three times the infiltration compared 

to moldboard-plowed soil. 

Soil porosity and infiltration are likely to continue to 

increase the longer the soil is under no-till and is accumulating organic matter. Other benefits of reducing soil 

disturbance include increased biological activity by arthropods and soil microbes, deeper rooting depth for crops, 

and the surface residue that protects the soil from temperature extremes.

More on Farm-Scale Composting

A SARE-funded project at Oregon State University 

led to development of an agricultural composting 

and water quality bulletin. It provides detailed, stepby-step guidelines on how to develop a composting 

enterprise on the farm, regulatory considerations and 

impacts on water quality.

Learn more:

https://catalog.extension.oregonstate.edu/em9053

https://projects.sare.org/sare_project/ow10-329

No-till soybeans emerge 

through corn stubble on 

a Pennsylvania farm. 

Photo by Edwin Remsberg

Composted dairy manure is an excellent soil amendment 

that improves organic matter, infiltration and 

waterholding capacity. Photo by Rob Myers, North Central SARE
www.SARE.org 9

Part Two 

Plant Management

SELECTING PLANTS ADAPTED TO INDIVIDUAL FARM AND 

ranch conditions is an important part of a water management strategy. Consider drought-tolerant varieties for 

water efficiency. Plants with deep root systems, such as 

buffalo grass, can stretch to the water table. Rangeland 

species—cool-season grasses ideal for cool-climate 

pastures or warm-season plants for hotter zones—can 

thrive in dry conditions.

Crop Rotation

Crop rotation is one of the most effective ways to manage 

water resources nationwide. Since farmers began growing 

grain, particularly in the Great Plains, they’ve used long 

periods of fallow to conserve water for wheat and other 

cash crops. The fallow system leaves the land bare over a 

year or more and allows water to accumulate in the soil. 

More recently, farmers and researchers turned to crop 

rotation as an alternative. They find that rotations improve 

soil health, conserve water and achieve better profits.

Crop rotation using cover crops is one way to enhance 

soil health and subsequent crops while also helping to 

maintain cleaner surface and groundwater. Cover crops 

prevent erosion, improve soil physical and biological properties, and supply nutrients to the next crop. They also 

suppress weeds, improve soil water availability and break 

pest cycles. Individual benefits will vary by species, crop 

productivity and how long a cover crop grows before soil is 

prepped for the next crop. Learn more about selecting and 

managing cover crops in Managing Cover Crops 

Profitably (www.sare.org/mccp).

Water-Conserving Plants

Certain varieties of grain crops can perform well in dry 

conditions and can help conserve moisture. Likewise, 

certain cover crops help farmers and ranchers conserve 

soil moisture. Look for crops that work in your specific 

climate and that might provide a market advantage.

For example, cotton is a significant water user. Texas 

accounts for 45 percent of the total U.S. cotton supply, 

with most of that concentrated in the state’s High Plains 

region. Water levels are declining at an alarming rate in 

the Ogallala aquifer, the main water source for Texas 

cotton.

Long-term research led by the Texas Alliance for 

Water Conservation and funded in part by SARE has 

shown that rotating cotton with perennial forages that 

are adapted to dry conditions uses 24 percent less water 

than a cotton monoculture. What’s more, such a diversified system opens a door to profitable beef marketing 

opportunities.

When plant residue is left on the soil surface, water 

infiltration increases and evaporation decreases, so there 

is less moisture stress during drought. Lightly incorporated cover crops can trap surface water and add organic 

matter to increase infiltration to the root zone. 

Especially effective at covering the soil surface are 

grass-type cover crops, such as rye, wheat and a sorghum-sudangrass hybrid. Some water-efficient legumes, 

such as medic and Indianhead lentils, provide cover crop 

benefits in dryland areas while conserving more 

moisture than fallow. 

White Sonora wheat 

(left) and Chapalote flint 

corn (right) are examples 

of drought-tolerant crops 

that can be used to 

diversify crop rotations 

in arid and semi-arid 

regions. Photos by Native 

Seeds/SEARCH
10 www.SARE.org

A research site in 

Nebraska includes field 

peas (left) as an 

alternative to summer 

fallow (right). 

Diversifying rotations 

with field peas is helping 

many farmers in this 

semi-arid region 

conserve water, improve 

soil health and adapt to 

market fluctuations. 

Photo by Strahinja Stepanovic, 

University of Nebraska Lincoln 

Extension

Profile: From Fallow to Field Peas

As farmers in western Nebraska face higher cash 

rents and property taxes, many want a more profitable, sustainable alternative to fallow for crop 

rotation. Strahinja Stepanovic, a University of 

Nebraska Lincoln Extension educator, received a 

SARE grant to find suitable crops for the mix.

“Farmers in the semi-arid regions of western 

Nebraska (14–19 inches of annual precipitation) who 

have no irrigation often conserve soil water by rotating cereal crops, such as corn or wheat, with a period 

of summer fallow,” says Stepanovic. “Unfortunately, 

fallow expenses are increasing due to development 

of herbicide-resistant weeds, record-low wheat prices 

and low protein levels. Farmers are slowly abandoning 

the fallow concept and are searching for alternative 

crop rotations. We have shown that pulse crops like 

field peas and chickpeas are a solid alternative to 

fallow.”

 Stepanovic notes that before 2013, only 10,000–

20,000 acres of field peas were grown in the 

Nebraska panhandle. Between 2014 and 2018, as 

farmers became familiar with peas through research 

and outreach efforts by Stepanovic and others, 

acreage grew to 70,000 and spread into central and 

eastern Nebraska. Production is slated to continue to 

expand.

“Replacing fallow with field peas has helped many 

farmers intensify and diversify crop rotations, 

improve soil health and better cope with herbicideresistant weeds and weather- and market-related 

fluctuations,” asserts Stepanovic. “Adding field peas 

to crop rotations helps conserve moisture.”

Stepanovic says that in 2018, precipitation was 

above average at 22 inches from March to September. 

On fallow ground with 60% residue cover, 19 of those 

inches were lost to percolation into the aquifer (11 

inches) and evaporation (8 inches), with 3 inches 

stored in the soil profile for fall-planted wheat.

“Water is way too valuable to lose,” Stepanovic 

states. “We can ‘harvest’ 11 inches of water as a 

30-bushel-per-acre pea crop and still not lose as 

much water as during fallow.” Field peas are a shortseason crop (March to July), and if the soil water 

profile regenerates between field pea harvest and 

wheat planting in September, the yield impact on the 

next year’s wheat crop may be negligible, he adds.

Depending on the year, farmers may report gains 

of $50 per acre. That is a significant improvement 

compared to $40–$90 per-acre expenses associated 

with spraying herbicides to control weeds in fallow. 

Additionally, three pea processors are now located in 

Nebraska along with about eight seed companies, so 

getting good quality seed and marketing are much 

easier now.

New research conducted since the SARE-funded 

project also is positive for pea farmers. Stepanovic 

notes one farmer planted field peas under pivot irrigation on sandy hills where irrigated corn yields were 

not attractive. In the dryland corners, field peas 

produced a 15-bushel yield while the same variety 

under pivot made a 65-bushel yield by supplementing only 1.5 inches of water applied at the right time. 

“We learned if you irrigate properly, you can get 

50–60 bushels of peas by applying only two or three 

inches of irrigation water, and then double-crop 

forage sorghum with no additional fertilizer or chemical inputs. That adds three to five inches of irrigation 

water between July and October to turn a pretty 

good profit,” Stepanovic says. Contrast that to a highinput crop like corn that requires more than 13 inches 

of water on sandy ground to make 180 bushels per 

acre, he adds. “This is how to save water with crop 

rotation. This is the most fundamental way to 

manage water.” 

Learn more: https://projects.sare.org/sare_

project/onc16-021
www.SARE.org 11

Heritage Grains

Native Seeds/SEARCH, an organization in Arizona that 

promotes arid-adapted crop diversity, worked with a team 

of farmers and researchers to successfully reintroduce two 

heritage grains to the arid Southwest. Supported by a 

SARE grant, the team evaluated Chapalote flint corn and 

White Sonora wheat for their capacity to reduce water use 

and enhance both soil fertility and moisture-holding 

capacity. They chose Chapalote corn for its reputation of 

performing well during dry years with little supplemental 

irrigation. White Sonora wheat was similarly selected for its 

drought tolerance. Using these heritage varieties, they 

reduced their seed, water and nitrogen inputs by up to 50% 

compared to conventionally grown varieties. Native Seeds/

SEARCH restored local production of this heritage grain 

and helped support the community by enlisting members 

to produce value-added products from the grain.

Regional Crops

Researchers and farmers in different states have evaluated 

such water-conserving species as hulless barley, quinoa 

and pearl millet. Washington State University researchers 

in the Palouse region of Idaho and Washington tested 

hulless barley and quinoa on dryland, no-till farms for 

seeding rate, nitrogen supply and yield. Evaluation of 

quinoa revealed farmer enthusiasm, but continued 

research is needed on combining agronomic practices 

with varieties that can tolerate drought conditions. Results 

with food-grade barley were much more favorable. Barley 

yielded reliably across three years of research on participating farms, and the team identified optimum seeding 

and fertility rates. They released a new cultivar of hulless 

barley with nutritional characteristics that are attractive to 

the health-food market.

Pearl millet is one of the most drought-resistant 

commercial grains. It can grow in areas that experience 

frequent dry weather during the plant’s vegetative or 

reproductive phases. This warm-season annual grass has a 

high protein content and a short maturing season that 

allows it to fill a midsummer, double-crop production 

niche. Pearl millet appears to be more tolerant of sandy 

and acidic soils than other summer crops, is deep rooted, 

and takes up residual nitrogen, phosphorus and 

potassium. The grain is used in poultry and livestock 

rations, and is a good option for wildlife plantings and 

birds. Opportunities also exist in health-food outlets and 

in beer brewing. 

Other drought-tolerant crop alternatives, especially in 

the South, include sesame and cowpeas.

Rangeland Drought Management

Ranchers must prepare for the ever-present challenges 

posed by drought. They need practical ranch management 

options during drought to sustain soil health, plant 

diversity and livestock production while supporting rural 

economies in the western United States.

Rangeland livestock producers are often the first to feel 

the impacts of drought, especially in California, where the 

majority of precipitation and forage growth occurs in fall, 

winter and spring. Ranchers report lost grazing capacity 

and profits, as well as reduced calf weaning weights during 

dry years. And many are not prepared for frequent 

drought events. 

Early Weaning Options 

In a SARE-funded project that began in 2018, University of California rangeland specialists partnered with local ranchers to assess early weaning of beef 

calves as a drought management strategy. In a producer survey conducted 

prior to and following the conclusion of California’s 2012–2015 drought, 

project coordinators learned that while early weaning is done by significant 

numbers of ranchers, very little research has been conducted in annual 

rangeland systems to determine whether such a strategy is economically or 

ecologically beneficial. 

While the project is ongoing, researchers learned during the first season 

that, as expected, early weaned calves were significantly lighter than traditionally weaned calves and did not gain as rapidly post weaning. Early 

weaned cows recovered their body condition score more rapidly than traditionally weaned cows, which may have 

bearing on conception rates in years following drought. The project team aims to develop guidelines that help individual ranchers decide when and how early weaning might work as a drought management strategy.

Photo courtesy Dan Macon, 

University of California 

Extension
12 www.SARE.org

Ken Tate, University of 

California Davis 

Extension specialist, 

advises ranchers to keep 

hay on hand to avoid 

paying a premium for it 

during a drought. Here, 

hay is fed to cattle 

during the 2015 drought 

in California. Photo by Tracy 

Schohr, University of California 

Cooperative Extension

Profile: Adapt-or-Perish Approach 

In 2013–14, University of California Davis Extension 

Specialist Ken Tate interviewed ranchers and asked if 

their current management strategies would be sufficient to deal with more frequent drought events (5–8 

drought years in a 10-year period). Most (82%) did not 

think so, and more than half said they would reduce 

their base herd size as a result.

Better options exist, however, according to Tate, 

whose effort to help ranchers adapt to more persistent drought was funded by SARE. “We can place 

management strategies into two bins: proactive in case 

of drought and reactive when there is drought. The 

best adaptive capacity is to have a good mix of both 

of these strategies as part of an actual drought 

management plan.”

Proactive strategies for cow-calf ranchers, 

particularly:

• Stock the herd at a moderate level with a safe 

number of animals should drought occur. Tate 

advises ranchers to protect their herd’s genetics 

and not to impulsively add or sell cows from their 

basic herds at random in response to adverse 

weather. 

• In good years, scale up the number of short-term 

tenants on pastures to use up forage. Consider 

buying 500–600 pound stockers and putting them 

on grass. 

• Keep 10 percent of a ranch’s forage in a resting 

state, or stockpile for emergencies. 

• Keep hay on hand so you don’t have to buy it 

during a drought.

• Be aware of specific financial risks and evaluate 

drought insurance. 

• Be aware of federal and state programs for 

drought aid. Track the federal drought monitor 

and provide input for your region so it is 

accounted for in aid packages. 

Reactive strategies for cow-calf producers:

• Determine which cows you would cull first during 

the drought and why. Cull open cows, old cows or 

bad-temperament cows first. 

• Have price triggers in your drought plan. Watch the 

market as drought begins to have an impact and 

sell if you can get a good price. 

• Replace feed with hay and realize you can’t feed 

your way out of a drought. Decide how long you 

are willing to invest in feeding cows before culling 

a second or third group. 

“Water management is another priority. Producers 

need a strategy to handle water availability,” Tate notes. 

“It is a pain to haul water to cattle, but if you do not 

have enough stock tanks, ponds or creeks then you 

need to have a plan to improve water distribution so 

cows can access forage that may be farther away from 

existing water sources. That makes more forage 

available.”

For example, keep a water truck that you can take to 

the cattle full during a drought. Explore USDA costshare dollars to put in equipment for improved water 

management. Tate adds that either option can be labor 

intensive but should be analyzed for long-term 

opportunities.

“No one thing will get you through. Successful ranchers 

are those who are willing to be risk takers and try new 

things,” says Tate. “Ranches on the same ground for generations have people who know what works locally. They are 

good resources for other ranchers.” 

For the long term, Tate encourages ranchers 

concerned about climate change or more frequent 

periods of dryness to weigh other options, including 

genetic selection to reduce cow size, adding or switching cattle breeds, or exploring opportunities with other 

ruminants.

“Take an adapt-or-perish strategy,” he states. 

“Switching breeds is not easy, but maybe it is a consideration. Sheep offer greater flexibility in forage and 

crop residue consumption and can be transported 

closer to urban areas for grazing than cattle can. Just 

don’t rush into a new enterprise. Match livestock to the 

environment and anticipate it not to be a good year 

every year.”

Other rangeland management specialists have found 

that adding small ruminants, such as goats and sheep, 

to a cattle operation can deflect the effects of drought. 

Large and small ruminants have different forage requirements. In addition, when drought strikes, common 

advice is to make the most of forage. Send the herd to 

graze drought-stricken crops to salvage the value of 

those crops, but monitor residues from droughtstressed crops for prussic acid and high nitrate levels.

Learn more: https://projects.sare.org/sare_project/

sw10-073
www.SARE.org 13

Part Three 

Water Management

FARMERS AND RANCHERS IN MANY PARTS OF THE COUNTRY 

are taking steps to make irrigation systems more efficient 

and cost effective. Regardless of which irrigation system 

you use, there are common ways to improve your management of irrigation water.

Improve soil health. The soil management practices 

described in this bulletin increase organic matter, aggregation, infiltration, waterholding capacity and rooting 

volume. They reduce crusting, erosion and surface evaporation. All of this maximizes a crop’s ability to use the 

irrigation water you apply.

Use water conservatively. Schedule irrigation 

times and amounts based on data from soil moisture 

sensors and weather forecasts, and based on the needs of 

the crop at different growth stages. Work with local specialists to determine the best ways to integrate sensor 

technologies on your farm. There may be other ways to 

modify your irrigation system to make it more efficient or 

opportunities to replace one system for another. Careful 

water management can also help manage salinity issues.

Harvest and reuse water. Water storage systems 

can be used to catch and store rainwater to supplement 

your needs, depending on your state and farming circumstances. If available, explore options for using good-quality 

recycled wastewater. EPA’s Guidelines for Water Reuse 

may help you find out your state’s regulations.

Contact an NRCS technical service specialist to develop 

an irrigation management plan that will control volume, 

frequency and flow rate to promote desired crop response, 

optimize water use, improve water quality, minimize 

irrigation-induced soil erosion, manage salts in the root 

zone and reduce energy consumption.

An irrigation audit may help determine what goals or 

outcomes are best for your individual farm. The Texas 

Water Conservation Implementation Task Force uses an 

audit with three phases: 

» Data collection. Key information may include 

sketches or maps of fields, locations of water 

supply networks, meters or measuring points, 

and inventories of pumping plants. Crop types, 

field slope, soil types and textures, and infiltration rates are also important. Irrigation 

scheduling method, previous water use data and 

prior audit results can also be significant, along 

with well construction information and well 

testing records. 

» Onsite audit. A physical irrigation audit should 

verify water use by assessing water and energy 

use efficiency across the farm. 

» Audit report. Data gathering and onsite audit 

phases should provide enough information to 

generate a report about current equipment, 

recent irrigation schedules and identified water 

uses throughout the operation. The irrigation 

audit report generally provides practical options 

for scheduling maintenance to improve irrigation 

systems and serves as a guidance tool for making 

innovative management changes.

In areas with frequent 

droughts or limited 

water availability, many 

producers are conserving 

water by adopting more 

efficient irrigation 

systems combined with 

improved soil 

management practices. 

Photo by Lance Cheung, USDA
14 www.SARE.org

Typical irrigation 

systems, which can have 

varying degrees of 

efficiency and cost, 

include (from top left): 

surface flooding, 

standard center pivot, 

center pivot with lowelevation application 

nozzles, drip, and mobile 

drip (a combination of 

drip tubes and lowelevation center pivot). 

Photos by (from top left): New 

Mexico State University 

Extension; Lance Cheung, USDA 

(second, third and fourth); and 

Kansas State University.

Irrigation Systems

Many irrigation packages and operating methods are 

available. For example, with proper design and installation, a center pivot sprinkler system can achieve high 

irrigation efficiency and uniform application. Furrow irrigation strategies, such as tailwater recovery, irrigating 

every other row and polyacrylamide application, also 

provide ways to lower water use. Other water delivery 

systems include lined on-farm irrigation ditches or 

pipelines, drip/micro and subsurface irrigation, gated and 

flexible pipes for field water distribution systems and 

surge flows. 

Types of Irrigation Systems

Surface irrigation supplies water to the soil surface by 

gravity. Surface irrigation systems can vary. Water flows 

over the ground and through the crop, with levees and 

gates used to control water depth, furrows or borders. 

Cascade flood irrigation involves water entering the field 

at the highest elevation and cascading down through a 

series of levee gates. Side-inlet flood irrigation involves a 

lay-flat pipe placed across levees with holes in it to simultaneously deliver water to each zone of the field. Surface 

irrigation systems are the cheapest to install and use, but 

water application rates are not exact and distribution 

across the field is typically uneven. They are most associated with salinization concerns because they may easily 

raise groundwater tables depending on the depth of the 

water table and how effective your drainage systems are. 

Flood irrigation is often less efficient than other systems 

due to the likelihood, depending on your circumstances, 

of experiencing higher rates of evaporation, deep infiltration or surface runoff. Techniques like land leveling, 

surge flooding, and capturing and reusing runoff can 

improve the efficiency of flood-irrigated systems.

Sprinkler irrigation applies water to crops via 

nozzles. Sprinkler systems use a water pump, or gravity 

in some cases, to build pressure and deliver water to 

crops through fixed or continuously moving nozzles that 

can be programmed to start and stop, such as with 

center pivot irrigation. Sprinkler irrigation works well on 

medium and coarse soils that have naturally higher infiltration rates. Sprinkler systems may be adapted to use 

on heavier soils by combining with practices like land 

leveling, tillage or diked furrows to help hold water while 

it infiltrates. Water can be applied at low rates with fertigation and chemigation, but frequent applications may 

be needed to recharge soils. Sprinkler irrigation 

improves efficiency compared to flooding systems by 

allowing for more precise water application rates. It does 

require a larger up-front investment and more energy 

use. Adaptations to center pivot and linear sprinkler irrigation systems can reduce water loss to evaporation and 

drift. These systems include:
www.SARE.org 15

Photo by Lance Cheung, USDA

» MESA, or mid elevation spray application, 

is a center pivot system where nozzles are spaced 

farther apart (10 feet) and the nozzles are higher 

(approximately 5–15 feet) off the ground. In 

MESA systems, water is delivered above the crop 

canopy. MESA can be less efficient than other 

systems because water applied above the crop 

canopy can be lost both to wind drift and to evaporation from the crop and soil surface. Use nozzle 

weights and flexible drop hoses to reduce water 

loss and improve water distribution.

» LESA, or low elevation spray application, is 

a modified center pivot system where the sprinkler nozzles are spaced closer together (less than 

5 feet apart) and are suspended closer to the soil 

surface (1–1.5 feet). LESA systems deliver water 

under the crop canopy and closer to the soil 

surface, so less water is lost to evaporation and 

wind drift. LESA irrigation systems run at low 

pressure, so they use less energy to pump water 

than MESA systems.

» LEPA, or low energy precision application, 

is a modification to typical center pivot systems 

that uses suspended nozzles to deliver water 

directly to furrows at lower pressures. Nozzles are 

typically spaced 60–80 inches apart, and water is 

delivered directly to the soil up to about 18 inches 

from the ground. The crop canopy stays dry since 

water is delivered close to the soil. Drag socks can 

be installed to minimize furrow erosion. LEPA 

irrigation systems work well with low-growing 

crops. They minimize water loss to wind drift and 

evaporation, and also optimize energy use since 

water is run at lower pressure.

Drip irrigation delivers water to crop roots; it is 

supplied under low pressure through plastic tubing with 

emitters to regulate flow rate. Tubing can be placed on the 

ground or buried beneath the soil surface. Drip irrigation 

is efficient with water by minimizing evaporation loss. It 

also reduces nutrient losses from leaching. More maintenance may be required for drip irrigation, but it offers a 

high level of control. Drip irrigation systems may be 

expensive to install, but reduced water and energy use, as 

well as potential yield increases, makes drip irrigation 

systems a good investment.

Mobile drip irrigation combines features of drip 

irrigation with the flexibility of center pivot irrigation. 

Mobile drip systems consist of trickle tape attached to a 

center pivot system that delivers water directly to the soil 

surface. Water loss to wind drift and evaporation are 

minimal under mobile drip systems. Energy savings may 

be significantly improved due to the low pressure needed 

to run these systems. 

Sub-surface irrigation delivers water beneath the 

soil surface through drip lines installed underground. The 

system is used to raise and maintain the water table near 
16 www.SARE.org

Profile: New Techniques Tweak Efficiencies

acres are irrigated, and more than 80 percent of them 

use furrow irrigation. During the last few years, 

Mississippi farmers have upgraded to technology tied 

to smartphones and computers. 

“We have demonstrated in the Delta region that 

combining furrow irrigation with technological 

advances, such as computerized hole size selection, 

irrigation timing using a soil water balance, and 

sensors for real-time feedback of plant and soil moisture conditions, can produce significant water 

savings,” says Curt Lacy, Mississippi State’s Delta 

Region Extension coordinator. 

Lacy and other Mississippi State Extension staff 

used a SARE grant to educate farmers on how to 

reduce water use through adoption of improved 

furrow irrigation management. On-farm demonstrations of the three tools validated practices, improved 

efficiency and uniformity, and saved water:

• Right-size holes are created by putting information regarding elevation and flow rates into a 

computer program. Holes are punched into 

pipes for uniform water distribution.

• Soil moisture sensors signal when to start and 

stop irrigation, and reduce water use.

• Surge irrigation valves are used to increase application efficiency.

Research shows that utilizing soil moisture sensors, 

computerized hole selection and surge irrigation in 

corn decrease total water applied by 39.5 percent 

while increasing corn grain yield by 6.5 bushels per 

acre and irrigation water use efficiency by 51.3 

percent. Net returns above irrigation costs rose from 

$25 to $40 per acre, according to Drew Gholson, a 

Mississippi State Extension irrigation specialist. 

Soybean returns and yield were unchanged as water 

use was reduced by 21 percent and water use efficiency increased 36 percent. 

“More than 18 trials showed statistically significant 

improvement in water use efficiency,” says Gholson. 

“Soil moisture sensors allowed farmers to prolong 

irrigation as long as possible without affecting crop 

development. Farmers should work with local 

Extension specialists on trigger thresholds best for 

their areas and on crop growth stages vulnerable to 

timely water application.”

Learn more: https://projects.sare.org/sare_

project/es16-127 

Furrow irrigation supplies water to crops through 

shallow, evenly spaced furrows. University of Missouri 

Extension describes it as, “parallel beds usually spaced 

30–38 inches apart. Water flows from a pump in layflat plastic pipes with holes in them to obtain desired 

flow rate.”

Though furrow irrigation is not very efficient on its 

own, the economics of it are attractive to farmers 

given little capital investment other than possible 

land grading. About two-thirds of Mississippi’s crop 

Soil moisture sensors 

that signal when to start 

and stop irrigation are 

installed in this soybean 

field at depths of 6, 12, 

24 and 36 inches. Photo by 

Drew Gholson, Mississippi State 

University Extension
www.SARE.org 17

the root line. This system is less labor intensive and is 

good for soils with low water retention capacity and 

smooth, level topography; it also can double as a drainage 

system. Tubing and emitters must be placed close to plant 

roots to be effective, and lateral water flow from the trickle 

line through the soil is limited.

Drain Water Management

Tile drainage systems are widely used to manage excess 

water in regions that receive a lot of precipitation. But 

when crop production practices that diminish soil health, 

such as excessive tillage and no crop rotation, are also 

used, then tile drainage systems do not operate as efficiently as they can because of poor water infiltration. This 

is why practices that improve soil structure, like conservation tillage and planting cover crops, and that result in 

increased water infiltration, are important for getting the 

most out of a drainage system. Excess water will flow more 

easily through the soil profile and into drain pipes instead 

of ponding or running off the surface.

In addition, fitting a drainage system with water 

control structures allows you to control the timing and 

amount of water leaving the field each year. Drainage 

water management, or controlled drainage, is a conservation drainage practice that focuses on managing the timing 

and flow of water leaving your drainage systems. 

Adjustable water-level-control structures allow you to 

raise and lower the water table (Figure 3). This gives 

farmers some flexibility and opportunity to manage their 

soil water table throughout the year, especially during 

excessively wet or dry periods.

Water levels are typically managed at key times during 

the growing season. Raise the water table after harvest in 

order to keep water and nutrients in your fields. Two 

weeks before planting or before any scheduled field activities, lower the water table to allow the field to fully drain 

so you can safely operate equipment without impacting 

the soil. Raise the water table near your crop root zone 

after planting. Effective management of drainage water 

can provide benefits, such as reducing the nitrogen lost as 

nitrate from fields by up to 40% and reducing annual 

FIGURE 3. EXAMPLES OF HOW A CONTROL STRUCTURE IS USED TO MANAGE FIELD DRAINAGE

A: The outlet is raised after harvest to reduce nitrate delivery to ditches and streams in the off season. B: The outlet is lowered a few weeks before 

planting (and again before harvest) to allow the field to drain more fully before machinery is operated. C: The outlet is raised after planting and 

spring operations to increase water storage for crops during the summer. From Drainage Water Management for the Midwest: Questions and Answers about Drainage 

Water Management for the Midwest (WQ-44), Purdue Extension.

Outlet

A B C

Drainage water 

management reduces 

the flow of nitrates to 

water ways and can 

make more water 

available to crops. 

Photo by Curt McDaniel, USDA
18 www.SARE.org

water discharge by 20–40%. In drier years, crop yield may 

increase by up to 10%. Further environmental benefits of 

controlled drainage are improved wildlife habitat, reduced 

erosion and cleaner water. 

Controlled drainage systems may be retrofitted onto 

older systems. Newer systems offer automatic controls, 

cellular data collection and weather monitoring. Work 

with your local technical service providers and Extension 

agents to develop a drainage water management plan that 

works for you. Cost-share programs are available through 

NRCS and your state’s department of agriculture to help 

manage the costs of improving your system. 

Managing Salinity

As salt accumulates in the soil, crops have more difficulty 

taking up the water that’s available. High salinity in the 

root zone also causes nutrient imbalances and affects plant 

growth and yield. High concentration of specific ions can 

be toxic to crops. 

Salinization occurs when irrigation water evaporates, 

which leaves salts behind. It is especially prevalent with 

flood irrigation systems, which tend to over apply water 

and can raise saline groundwater tables. Once the water 

table gets close to the surface, capillary water movement 

transports soil water to the surface, where it evaporates 

and leaves salts behind. When improperly managed, this 

can render soils unproductive within a matter of years.

The adverse effect of salinity can be reduced through 

proper irrigation and crop management practices, such as 

leaching, selecting plants like barley or alfalfa that can 

tolerate salinity or specific ions, and soil/water amendments. Testing for salinity and sodicity in irrigation water 

and soils can help you develop irrigation and crop 

Manage Salinity with Cover Crops

In the Northern Plains, extensive wet periods lead to salinity problems on an 

estimated 15–35% of cropland. Creating cropping systems that use more water 

and that drive salts deeper into the soil profile is one recommended strategy for 

addressing this challenge. Funded by two SARE grants, North Dakota State 

University Extension specialists partnered with area farmers to demonstrate how 

crop rotations involving cover crops can manage salinity while providing other 

soil-health-related benefits.

The team worked with four farmers to implement rotations on salt-affected 

fields. They were able to extend the amount of time a crop was growing in 

those fields by up to four months by combining cover crops with an early 

season, salt-tolerant crop, such as a small grain. Along with better management 

of excess moisture, these rotations that extended the length of the growing 

season also improved soil health and developed more sustainable agronomic 

systems. The cover crops used on each farm were mixes that included cereal rye, 

radishes and turnips, plus additional species in some treatments.

Learn more:

https://projects.sare.org/sare_project/ONC15-012

https://projects.sare.org/sare_project/ONC17-036

Water Harvesting

Farmers with greenhouses, high tunnels and other structures with significant roof 

area can consider installing systems to capture and store rainwater for irrigation. 

Capturing, storing and pumping the water that falls on such rooftops can be an 

attractive way to supplement other sources of irrigation water.

Cherry Flowers and Tim Page operate an urban farm in the Twin Cities area of 

Minnesota, and they saw many positives to adding a rainwater harvest system to 

their high tunnel, which they did with support from a SARE grant. It consists of 

gutters lining both sides of the structure, which drain into rain barrels. The barrels are 

connected to the drip irrigation system inside the tunnel, and water is pushed 

through by a solar-powered pump. The system can capture 600 gallons of water in a 

1-inch rainfall, and in the first year of use, there were only four rain events that 

exceeded the capacity of the system.

Along with using rainfall to irrigate the crops inside the tunnel, Flowers and Page 

have found other benefits of the system: it allows them to avoid chemicals that are 

found in municipal water and are potentially harmful to crops, such as flouride and 

chlorine; it eliminates erosion and ponding around the inner and outer edges of the 

high tunnel, which used to occur during heavy rainfalls; and it reduces the amount of 

stormwater their operation contributes to the municipal sewer system.

The rainwater harvesting system that Cherry Flowers and 

Tim Page added to one of the high tunnels at their urban 

farm in Minnesota. Photo by Marie Flanagan, North Central SARE
www.SARE.org 19

Apply Nitrogen and Phosphorus with Care to Protect Water Quality

Managing soil phosphorus is a concern for farmers and environmental regulators. 

Over-applying phosphorus in composted or uncomposted animal waste may 

contribute to surface water pollution. Although nitrogen and phosphorus are 

essential for plant nutrition, excessive amounts can wash and leach into 

waterways.

The first step for keeping nitrogen and phosphorus in fields and out of surface 

waters is to rely on regular soil testing and to maintain soil nutrient levels that 

support plant growth but do not accumulate beyond optimal levels. NRCS recommends soil testing fields every three to five years. Any nitrogen and phosphorus 

added through bio-solid or manure applications should be accounted for when 

determining how much plant-available nitrogen and phosphorus is required to 

reach the levels recommended by a soil test. 

Experts suggest analyzing the phosphorus and nitrogen contents of compost as 

part of nutrient management planning. Routine testing is both recommended and 

widely available. Test soil—as well as organic amendments such as compost—for 

nitrogen and phosphorus levels, and test compost for moisture content. Each 

state’s soil testing lab, typically located at land grant universities, can also provide 

information about the phosphorus index (PI) to measure phosphorus 

concentration.

The NRCS recommends using one of three phosphorus application options 

when manure or other organic byproducts are land applied:

• PI rating: nitrogen-based manure application on low- or medium-risk sites, 

phosphorus-based or no manure application on high- or very-high-risk sites

• Soil phosphorus threshold values: nitrogen-based manure application on sites 

where the soil test phosphorus levels are below a threshold value, phosphorus-based or no manure application on sites that equal or exceed threshold 

values

• Soil test recommendation: nitrogen-based manure application on sites where 

there is a soil test recommendation to apply phosphorus, phosphorus-based 

or no manure application on sites where there is no soil test recommendation 

to apply phosphorus

management practices that will sustain crop yields, 

maintain or improve soil physical properties, and 

minimize adverse environmental impacts. 

One option is to keep soils moist. Drip irrigation with 

low-salt water plus a surface mulch does not allow salt 

content to get as high as it would if allowed to concentrate when the soil dries. Another option is to grow 

saline-tolerant crops like barley or Bermuda grass. 

The only way to get rid of salt is to add sufficient water 

to wash it below the root zone, which requires significant 

amounts of water and time. If the subsoil does not drain 

well, drainage tiles might be needed to get rid of salt 

water. In arid regions, where shallow groundwater tables 

and less precipitation is common, irrigation management 

systems should be designed to both supply and drain 

water to avoid the issues that contribute to salinity accumulation in soil. 

Smart Irrigation

Unlike traditional irrigation controllers that operate on a 

preset schedule to deliver a uniform amount of water 

across a field, variable rate irrigation systems allow you 

to change the water rate either from one irrigation event 

to the next, or to apply different rates in various zones of 

a field during a single event. These systems use data 

from sensors monitoring soil moisture, weather conditions and crop plants, combined with analysis software 

and irrigation system controls, to automatically adjust 

irrigation schedules based on actual conditions. These 

systems are becoming more sophisticated in their ability 

to determine the precise needs of individual crops and to 

account for variability across fields in terms of both soil 

type and moisture level.

Basic systems can start with soil moisture sensors 

that are placed at varying depths and in multiple field 

locations. These sensors can be connected to smartphones and can help you recognize when soil-moisture 

levels are adequate to reduce a scheduled application of 

water, or to skip it entirely.

Contact local specialists with NRCS, Extension or 

irrigation suppliers to explore strategies for adopting 

sensor technology on your farm or ranch.

Regularly test soil to avoid over-application of nutrients. Photo by Jason Johnson, Iowa NRCS
20 www.SARE.org

This bulletin was written by Barb Anderson. It was produced by Sustainable Agriculture Research and 

Education (SARE), supported by the National Institute of Food and Agriculture (NIFA), U.S. Department of 

Agriculture under award number 2019-38640-29881. USDA is an equal opportunity employer and service 

provider. Any opinions, findings, conclusions or recommendations expressed in this publication are those 

of the author(s) and do not necessarily reflect the view of the USDA.

Resources 

Profile: Low-Cost Irrigation Technology Ideas

Efficient irrigation management is important for all farms regardless of their size, 

but some small-scale growers find that the cost of commercial technology puts it 

out of their reach. This motivated Christian Flickinger of Renegade Acres in Howell, 

Mich., to create a low-cost, automated irrigation system using a mix of commercialand professional-grade components. The system, which Flickinger developed 

through a SARE-funded project, is controlled with open source technology, meaning 

other farmers can easily adopt a similar approach and modify it based on their 

irrigation needs.

The web-based controller in Flickinger’s system includes flexible programming 

options with the capability of reducing irrigation schedules based on real-time 

weather patterns, which is helpful when managing the water requirements across his 

diversified, 7-acre operation. He used consumer-grade solenoid valves and professionalgrade drip tape to complete the system. In 2017, his first year using the new system, 

he reduced his water use by 58%, or by more than 58,000 gallons, compared to 2016. 

Both years had similar weather patterns. The savings were a result of irrigating less 

frequently and for shorter periods of time because his schedules took weather 

conditions into account.

The low-cost irrigation system set up by Michigan farmer Christian Flickinger includes a 

mix of commercial and professional components (top) that is controlled by web-based, 

open source technology (bottom). Photos by Christian Flickinger

Cost-Share Resources

USDA’s Conservation Stewardship Program provides financial 

and technical assistance to eligible producers to conserve and 

enhance soil, water, air and related resources on their land.

The NRCS Environmental Quality Incentives Program (EQIP) 

provides producers with financial resources and one-on-one 

help to plan and implement conservation practices that lead 

to cleaner water and air, healthier soil and better wildlife 

habitat, all while improving agricultural operations. 

The USDA’s Agricultural Management Assistance program is 

available in 16 states to help producers implement 

conservation practices that reduce financial risk and that can 

be used to construct and improve water management and 

irrigation structures. 

To further explore sustainable water management, read this bulletin online at www.sare.org/water-bulletin, where you will find links to additional resources that 

were developed by SARE and by SARE grantees. General resources that are free to access online:

Soil and Plant Management

Building Soils for Better Crops

www.sare.org/bsbc

Cover Crops for Sustainable Crop Rotations

www.sare.org/cover-crops

Crop Rotation on Organic Farms

www.sare.org/crop-rotation-on-organic-farms

Cultivating Climate Resilience on Farms 

and Ranches

www.sare.org/climate-resilience

Managing Cover Crops Profitably

www.sare.org/mccp

Rangeland Management Strategies

www.sare.org/rangeland

Water Management

USDA Natural Resources Conservation Service 

(NRCS) irrigation page

http://go.usa.gov/Kow

Contact your local Extension or NRCS office for 

site-specific irrigation information.