Agriculture and Natural Resource Protection

What shape is your farm in?

Agriculture is second only to forestry as a form of land use in North Carolina. Agricultural production occurs on over six million acres or 19 percent of the land. Agriculture is an intensive activity involving the management of soil, water, animals, and crops to produce food and fiber. We know that the operation of the farm can cause a wide range of impacts on the environment depending on the production practices. This self-assessment will allow you to evaluate your agricultural practices in relationship to natural resource protection.

How can we help?

This publication can help you focus on potential problems and solutions that will help you manage your farm to maximize yields while preserving natural resources—wildlife and water quality. Gather any records that you may need to help you answer any of the questions.

Each of the following sections deals with a different topic. Each topic is a question for you to answer. Your answers will help you to see where you may have potential problems.

• If you answer a question with a or b, you have few problems.
• If you answer a question c or d, your agricultural practices may be degrading natural resources.
• If you answer a question c or d, you will want to consider making changes in order to maintain profitable agricultural practices while protecting natural resources.

For further help in assessing the conditions on your farm, visit your nearest Cooperative Extension Service Center, your local Natural Resource Conservation Service office, or your North Carolina Soil and Water Conservation District office.

What kind of natural resource steward are you?

Environmental stewardship can be part of your production practices. Why? Because once groundwater becomes polluted with agricultural chemicals, it is nearly impossible to clean up. At that point, the only ways to get safe drinking water are to treat the water, drill a new well, or obtain water from another source. All of these options are expensive and inconvenient. Clearly, it is easier to protect our natural resources in the first place than to restore them.

Some practices in our homes and on our farms can pollute our groundwater and surface waters and may reduce wildlife habitat and populations. The North Carolina Farm*A*Syst publications will lead you through an evaluation of your farmstead and agricultural practices to determine if you are protecting natural resources while maintaining a viable farm. If there is a problem or a potential problem, the Farm*A*Syst publications have information about how to solve the problems. The publications also list the North Carolina state agencies responsible for helping you solve your agricultural problems.

The goal of the North Carolina Farm*A*Syst program is to help you protect the natural resources that all North Carolina residents depend on, while maintaining viable agricultural production practices.

Water quality: What is it and why is it important?

For many years we used our water resources as waste disposal systems, dumping raw sewage and industrial wastes into rivers and lakes. In 1972, the U.S. Congress took action and passed the Clean Water Act. This reduced the amount of pollution that was directly discharged. During the past 25 years, we have increasingly recognized a different type of pollution, called nonpoint source pollution. It is different from the direct discharge sources because it comes from large areas instead of a pipe below a factory or sewage plant. There are many sources of this pollution—soil erosion, construction sites, and agricultural fields.

The water resources in North Carolina most affected by pollution are streams and rivers, followed by lakes and ponds. Only 40 percent of the streams and rivers are meeting their designated uses such as swimming, fishing, and drinking. Approximately 75 percent of the lakes and ponds and 95 percent of the estuaries are meeting their uses. Approximately 50 percent of all water pollution is caused by agricultural activities, much of that coming from erosion. In order to reduce nonpoint source pollution, it is important that good agricultural practices that produce high yields while preserving our natural resources be used. The surest way to have waters that are safe for drinking, recreation, and aquatic habitat is to protect them before we pollute them.

How do we fit in?

Each of us lives in a river basin, so what we do on the land ends up affecting water quality. River basins are simply the areas that drain into a river. North Carolina is divided into 17 river basins: the Broad, Cape Fear, Catawba, Chowan, French Broad, Hiwassee, Little Tennessee, Lumber, New, Neuse, Pasquotank, Roanoke, Savannah, Tar-Pamlico, Watauga, White Oak, and Yadkin.

Once water begins to run over the land, it can pick up pollutants, such as pesticides, sediment, or phosphorus. As water continues to move into streams, these pollutants are carried along with the runoff. These streams and tributaries then deliver their pollution load to lakes, rivers, estuaries, or oceans. Reducing or eliminating pollution from farms helps protect small streams on the farm as well as the waters downstream. Most practices that producers use to reduce or control pollution also protect the farm resources and often actually save producers money.

What are the Pollutants of Concern?

1. Why does sediment cause problems?

Excessive sediment from eroding cropland and overgrazed pasture affects water resources. Sediment reduces the storage capacity of certain water resources, such as lakes and ponds, and it destroys fish and wildlife habitat. Sediment in the water makes it harder for fish eggs to survive and can clog gills. Water treatment also costs more because of excess sediment.

Water erosion is the natural process of soil movement from higher areas to lower areas by the action of water flowing downhill. During a storm, precipitation rates usually are greater than infiltration rates, resulting in an overland flow of water. This creates the potential for water erosion. Agricultural activities such as soil cultivation, the destruction of vegetative cover, and soil compaction accelerate soil erosion.

Many agricultural practices have been designed to reduce soil erosion. Some, such as grassed waterways, move water into channels and then off the fields. Others, such as contour planting and conservation tillage, are designed to slow runoff, hold the soil in place, and reduce soil erosion. Still others, such as field borders and grassed buffer zones, are designed to trap soil that is moving from agricultural fields.

Why do nutrients cause problems?

Nutrients (phosphorus or nitrogen) can enter water resources through surface runoff, either dissolved in the water or attached to soil particles. These nutrients are the primary cause of algal blooms. Algal blooms can kill fish, cause the water to be toxic, and make water taste bad. In addition, high concentrations of nitrate (10 parts per million) cause Blue Baby Syndrome, a condition in which nitrate interferes with the transport of oxygen in the blood of an infant. Without enough oxygen, the baby may turn blue and die. A recent North Carolina study of 1,719 drinking water wells found that 1.8 percent of the wells had nitrate-nitrogen levels at or above the danger level of 10 parts per million. Approximately 20 percent of the wells sampled contained elevated nitrate-nitrogen levels of between 4 and 9 parts per million, also risky. Nitrate-nitrogen concentrations were greater in wells in coastal plain counties, where 4.9 percent of the tested wells contained 10 parts per million nitrate-nitrogen or higher.

1. Circle the statement that best describes your soil conservation practices.

a. I prevent soil erosion by using conservation tillage.

b. I reduce soil erosion by using contour planting, and, if applicable, I use grassed waterways, field borders, grassed buffers and other soil conserving practices.

c. I reduce soil erosion by using contour planting only.

d. I do not use any soil conservation practices; OR do not know.

2. Phosphorus

The greatest amount of phosphorus pollution is delivered by overland flow of water that carries sediment. Most phosphorus is attached to soil particles. Therefore, agricultural practices that maintain adequate but not high levels of soil phosphorus and reduce soil erosion will reduce pollution from phosphorus. In addition, since animal waste is high in phosphorus, it is important to follow animal waste disposal rules, regulations, and guidelines. (For information regarding the proper handling and disposal of animal waste to reduce phosphorus, see Fact Sheet # 7, Improving the Storage, Handling, and Disposal of Livestock Waste.)

2. Circle the statement that best describes your phosphorus soil test.

a. My phosphorus soil test has a P-I of <75; I don't have erosion or I control soil erosion, and I am not near a stream or lake.

b. My phosphorus soil test has a P-I of <75; I don't have erosion, or I control soil erosion, and I am near a stream or lake.

c. My phosphorus soil test has a P-I of >75; I do not control soil erosion, but I am not near a stream or lake.

d. My phosphorus soil test has a P-I of >75; I do not control soil erosion, but I am near a stream or lake; OR do not know.

3. Nitrogen

Most nonpoint source nitrogen that enters surface waters moves into streams through groundwater. Surface runoff commonly contains low concentrations of nitrogen compared to groundwater flows from fertilized fields. Most nitrogen added to soils as commercial fertilizer or organic wastes is converted to nitrate-nitrogen, a mobile form of nitrogen that readily moves with soil water. As rainwater enters the soil and flows down through the rooting zone, the nitrogen is absorbed by growing plants, incorporated into the organic matter, denitrified, or moved into groundwater. The movement of nitrogen into the groundwater occurs most often during the winter when plants are not growing, but nitrate leaching also can occur in very wet periods during the spring or summer.

Once nitrate-nitrogen moves below the water table and enters the saturated zone, it will flow with the groundwater. In upland areas, groundwater tends to move down, driven by periodic rainfall that recharges the groundwater system. As the groundwater percolates downward, it frequently moves laterally toward streams. Nitrate that is carried with the groundwater eventually discharges into a surface-water body. The amount of nitrate entering the surface water can be reduced if the groundwater flows through a riparian buffer or discharges into a controlled drainage system, or if the amount of nitrogen that reaches the groundwater is reduced as a result of good management practices.

Managing nitrogen is important to ensure that only the amount needed by the crop is added. This is the essence of a nitrogen management plan: nitrogen supplied at the correct rate, time, form, and placement. Although nitrogen management will not prevent nitrate from leaching into the groundwater, it will reduce the amount.

Riparian buffers are trees, shrubs, or grass next to streams. Nitrate in groundwater that passes through a riparian buffer may either be taken up by the riparian vegetation or converted to a gas, through a process called denitrification, by bacteria found in the soil. In riparian soils, denitrification is an extremely important process for removing nitrate from groundwater flowing from fertilized fields.

A two-zone riparian buffer system (modified from Lowrance et al., 1995).

Ditches installed with boards at the drainage outlet (controlled drainage) can reduce nitrogen, if managed properly. Controlled drainage helps keep nitrogen out of the ditches in three ways:

1. More nitrogen is used by the crop since more water is available for plant growth.
2. Less water (and thus less nitrogen) leaves the field.
3. Nitrogen is denitrified as it moves from the field into the ditch.

Because nitrogen is essential for high crop yields, strategies to control it must involve either nitrogen management and controlled drainage or nitrogen management and riparian buffers.

3. Circle the answer that best describes your use of nitrogen management.

a. I use a nitrogen management plan, and I use controlled drainage or my streams are surrounded by trees, shrubs, or grass (riparian buffers).

b. I use controlled drainage or my streams are surrounded by riparian buffers.

c. I use a nitrogen management plan.

d. I do not use a nitrogen management plan, and I have no controlled drainage or streams surrounded by trees, shrubs, or grass (riparian buffers); OR do not know.

4. Fecal coliform

Fecal coliform contamination is caused by waste runoff, and the bacterial live only in warm-blooded animals, including humans. Fecal coliform contamination can cause human health problems, such as diarrhea. When health advisory levels for fecal coliform concentrations are exceeded, water resources are closed to swimming as well as harvesting of filter feeders (mussels, oysters). Currently, 18 percent of North Carolina's shellfish beds are closed to harvesting due to fecal coliform contamination.

4. Circle the answer that best describes the storage and application of your animal waste.

a. I store and apply my animal waste according to state guidelines, field borders are used around all spray fields, and streams are surrounded by riparian buffers.

b. I store and apply my animal waste according to state guidelines, and streams are surrounded by riparian buffers or field borders are used around all spray fields.

c. I store and apply my animal waste according to state guidelines, but I don't use field borders around spray fields or riparian buffers next to streams.

d. I do not store and/or apply my animal waste according to state guidelines; OR do not know.

5. Pesticides

Some pesticides may enter water resources through surface runoff, either dissolved in the water or attached to soil particles. In addition, pesticides can leach through the soil into the groundwater. Most surface water resources in North Carolina are not affected by pesticides, but there are some problems with pesticides in groundwater. In North Carolina, researchers found that 5 of 46 wells, or 12 percent of the drinking water wells tested, were above danger levels for the pesticides tested. Three of the pesticides are currently registered; two were formerly registered but are no longer used.

The most serious threats to groundwater and surface water can be reduced by storing and loading pesticides correctly (see Fact Sheet #5, Improving Storage and Handling of Pesticides). In addition, pesticide use and thus possible contamination can be reduced through integrated pest management (see Fact Sheet #9, Managing Pests). Finally, once a pest problem is identified and a pesticide is needed, the one least likely to leach to groundwater can be selected (see SoilFacts publication AG-439-31, Protecting Groundwater in North Carolina). Following label directions also reduces pesticide contamination.

5. Circle the answer that best describes your use of integrated pesticide management (IPM).

a. I use IPM in all my production practices, and I have an improved pesticide mixing and loading facility.

b. I have an improved pesticide mixing and loading facility.

c. I use IPM in most of my production practices.

d. I do not use IPM, and I mix and load on gravel or dirt near a well; OR do not know.

Contacts and References

Whom to call...

For answers to water quality questions, call the Division of Water Quality (DWQ), which is part of the North Carolina Department of Environment and Natural Resources. For information about best management practices, contact your local:

• North Carolina Cooperative Extension Service Center.
• Soil and Water Conservation District office.
• Natural Resources Conservation Service office.

Related publications:

• Agriculture and Coastal Water Quality. AG-439-10
• Best Management Practices for Agricultural Nutrients. AG-439-20
• Careful Soil Sampling - The Key to Reliable Soils Test Info. AG-439-30
• Good Soil Management Helps Protect Groundwater. AG-439-9
• Nitrogen Management and Water Quality. AG-439-2
• North Carolina Erosion and Sedimentation Pollution Control Program. AG-439-32
• Protecting Groundwater in North Carolina - A Pesticide and Soil Ranking System. AG-439-31
• Soils and Water Quality. AG-439-1

These publications are available at your county Cooperative Extension center. Publications with "AG" or "FCS" numbers may be ordered from Communication Services, Campus Box 7603, North Carolina State University, Raleigh, NC 27695-7603.

To Find Your State Division of Water Quality Location

• ¹Interchange Building, 59 Woodfin Place, Asheville, NC 28801; 828-251-6208

• ²505 Waughtown St., Winston-Salem, NC 27107; 336-896-7007
• ³3800 Barrett Drive, Suite 101, Raleigh, NC 27609; 919-571-4700
• ⁴1424 Carolina Avenue, Washington, NC 27889; 252-946-6481
• ⁵919 North Main Street, Mooresville, NC 28115; 704-663-1699
• ⁶Wachovia Building, Suite 714, Fayetteville, NC 28301; 910-486-1541
• ⁷127 Cardinal Drive Extension, Wilmington, NC 28405-3845; 910-395-3900

College of Agriculture & Life Sciences . NC State University
School of Agriculture . NC A&T State University

Prepared by

Deanna L. Osmond
Soil Science Extension Specialist

Rich McLaughlin
Soil Science Extension Specialist

Janet Young
Layout and Design Specialist

The concept for these materials was adapted from materials produced by the National Farm*A*Syst Program, University of Wisconsin, Madison, WI.

North Carolina's Farm*A*Syst and Home*A*Syst Program is coordinated by Deanna L. Osmond, North Carolina State University. Technical editing was provided by Judith A. Gale. Steve Hodges, George Naderman, and Michael Wagger provided technical reviews.

This project has been funded with Section 319 grant monies from the U.S. Environmental Protection Agency through the N.C. Department of Environment and Natural Resources, Division of Water Quality.

Published by

NORTH CAROLINA COOPERATIVE EXTENSION SERVICE

Distributed in furtherance of the Acts of Congress of May 8 and June 30, 1914. Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age, or disability. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.

AG-566-10
E00-38856

This document was updated on 9/13/00 by Janet Young.