Grass Seed Production and the Environment

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• Foreword
• Environmental Overview
• Production Overview
• Straw Residue Management
• Grass seed is an integral part of Oregon's economy
• Crop Pest Management
• Fertility Management
• Environmental and Social Benefits
• Credit

Environmental Overview

Grass seed crops contribute to clean air and water quality in ways few crops can. Sediment runoff to surface water is retarded in perennial grass seed fields because ground is covered during high rainfall months. Since perennial grasses are planted only every fourth of fifth year, tillage is limited and soil is protected by plant cover. Grass plants have extensive, fibrous root systems, which further reduces the potential for soil erosion and protects groundwater and streams from leached nutrients. Straw and stubble residue management systems recycle nutrients, conserve soil moisture and suppress weed growth.

Production Overview

Grass seed crops produced in Oregon are often grown in rotation with non-irrigated crops such as clover seed, wheat and meadowfoam, and with irrigated row crops such as vegetables and peppermint. Rotation crops can provide economic and plant diversity to farm operations, break weed and disease cycles and benefit wildlife.

Most grass seed crops are perennial and remain productive three to five years without annual reseeding. Grass seed crops can preserve and even enhance water quality by absorbing fertilizers and retarding the runoff of sediment and pesticides.

Grass seed production systems vary depending on the kinds of crops grown, farm size, soil type and slope, and pest pressure.

Straw Residue Management

Straw and stubble residue management systems have changed dramatically since the phase down of open field burning. Growers now use one of two residue management systems: They either leave all the straw on fields after seed harvest or bale off a portion for export to Asia.

Leaving all the straw on fields preserves soil moisture, improves soil tilth, protects soil from erosion, suppresses weed growth and reduces fertilizer and energy inputs. Leaving a portion of straw on fields after baling and flailing provides many of the same benefits and enhances plant re-growth. Open field burning, historically used to remove residue, is limited by the state of Oregon and practiced on less than 10 percent of the state's grass seed acreage. Some grass species are yielding as much now as when field burning was widely used, other species are showing significant yield reduction.

Grass seed is an integral part of Oregon's economy

Oregon growers enjoy an international reputation for producing high-quality grass seed. Here, approximately 60 percent of the world's cool season grass seed is produced. The many species and varieties grown in Oregon are used for beautification, recreation, erosion control and forage in North America, South America, Europe and Asia.

More than 95 percent of the grass seed grown in Oregon is produced in the Willamette Valley. At any one time, approximately 50 percent of the tillable land in the Willamette Valley-about 500,000 acres-is planted to grass seed.

Grass seed contributes significantly to Oregon's economy. Farm gate receipts for grass seed- nearly $340 million in 2000-make up 10 percent of the total farm gate receipts for Oregon. And grass seed injects hundreds of millions of dollars into peripheral industries such as shipping, packaging, sales and labor.

A percentage of straw left over after seed harvest is used as livestock feed. Straw dealers shipped nearly 500,000 tons of straw to Japan, Taiwan and Korea at a farm gate value of $50 million in the 2000 market year.

Crop Pest Management

Oregon grass seed growers produce a high-quality product in order to meet the demands of domestic and international markets. To achieve high-quality standards, crop protection inputs are needed to minimize losses from weeds, insects, rodents and diseases.

Herbicides are the most commonly applied crop protection input. Weeds can reduce seed yields by competing with plants for water and nutrients, and weed seeds can contaminate grass seeds, which lowers value and reduces marketability of crops.

Because the Willamette Valley is a diverse agricultural setting, growers take several steps to ensure proper herbicide placement. Herbicide applications are performed by trained applicators who use equipment designed to maximize application efficiency and control drift. Applicators rely on precise weather forecasts to apply herbicides under favorable weather conditions. Under a grass seed grower-funded program initiated in 1999, farmers access up-to-the-minute weather data during the growing season through a special radio frequency transmission from the Oregon Department of Agriculture.

Pressure from weeds, diseases and insects varies from year to year and can cause growers to alter the amount of herbicides, fungicides and insecticides annually applied. Seldom are the maximum allowable rates used in the site-specific, prescription-agriculture programs employed in the Willamette Valley.

Crop protection inputs and application methods are regulated by the U.S. Environmental Protection Agency, the Oregon Department of Agriculture and the Oregon Department of Environmental Quality. Research has shown that when used in accordance with label directions, crop protection inputs do not diminish water quality.

Fertility Management

Grasses use fertilizer more efficiently than most crops; as a consequence, less fertilizer is lost from fields due to nitrate leaching. Oregon grass growers have developed production practices that are designed to minimize the amounts of fertilizers applied while still attaining desirable yields. Among methods employed to reduce fertility input needs, growers leave straw on fields following seed harvest to recycle nutrients, and growers include legumes in crop rotations because legumes fix nitrogen to the soil and make it available to succeeding crops.

Most nitrogen inputs are applied in the spring when chances of losses to leaching and run-off are minimal. Under typical usage rates, nitrogen does not pose a threat to water quality due to the grass plant's extensive root system that is able to take up nitrates at a high rate.

Environmental And Social Benefits

Grass seed grown in Oregon is used around the world to plant pastures, parks and reclaimed areas. It also enhances the environmental quality of life in the Willamette Valley:

• Perennial grass seed crops preserve topsoil and contribute to clean air by reducing the need for tillage;
• Grass seed crops protect streams, lakes and groundwater by retarding sediment, fertilizer and pesticide runoff;
• Grass seed crops add to the aesthetic value of the Willamette Valley;
• And grass seed crops reduce greenhouse gases by absorbing carbon dioxide and releasing oxygen.

More than half of the world's cool
season grass seed is produced in
Oregon's fertile Willamette Valley.