Nutrient Management

Nutrient Management, Managing nutrients, whether it is synthetic fertilizer or manure and other organic fertilizers requires planning. Determining which type of fertilizer to apply, the application rate and timing are key factors in managing soil to improve crop yield and quality, reduce fertilizer costs and help protect the environment.

Nutrient Management

Applying Lime to Raise Soil pH for Crop Production - Soil acidification, or a decrease in soil pH, is a natural process that is accelerated by crop production practices, primarily the use of nitrogen (N) fertilizers such as urea, ammonium sulfate, or other fertilizers containing ammonium-N.

Eastern Oregon Liming Guide - Soils of the inland Pacific Northwest were generally alkaline before cultivation began, with the exception of some higher rainfall areas. Virgin soils contained highly variable amounts of carbonate. Today, however, broad areas, including the Columbia Basin and Palouse, have acidic soil (pH below 6.0) as a result of past farming practices.

Evaluating Soil Nutrients and pH by Depth - Collecting soil samples to a depth of 6 to 8 inches is standard protocol for western Oregon. When the sampling protocol was developed, this depth was typical of tillage for seedbed preparation. As well as preparing the seedbed, tillage controlled weeds and mixed nutrients and lime into the soil.

Pastures Fertilizer Guide - A single fertilization program will not fit all pastures. Determine which combination of grazing management, fertilization, and irrigation fits your resources and environment. Use a soil test and an assessment of forage supply and forage species to determine fertilizer need.

Monitoring Soil Nutrients Using a Management Unit Approach - This publication focuses on how to design a soil nutrient monitoring strategy that fits today's requirements for record keeping and increase accuracy in managing nitrogen, phosphorus, and other nutrients.

Nitrogen Uptake and Utilization by Pacific Northwest Crops - This publication provides information on the timing and pattern of biomass accumulation and nitrogen uptake for a variety of Pacific Northwest crops. You can use this information to schedule N fertilizer applications for maximum efficiency.

Post-Harvest Soil Nitrate Testing for Manured Cropping Systems West of the Cascades - This publication describes the use of post-harvest soil nitrate testing as a tool for assessment of nitrogen management in manured cropping systems west of the Cascade Mountains in Oregon, Washington, and south coastal British Columbia.

Agriculture Phosphorus Management using the Oregon/Washington Phosphorus Index - This publication provides research-based information to assist agricultural professionals and their clients in identifying conservation practices that may reduce phosphorus loss from a field.

Fertilizer and Nutrient Management Guides

Fertilizer Guides - A complete list of Oregon State University fertilizer guide publications by crop.

Fertilizing Lawns - This publication will help you better understand the reasons for fertilizing, optimum application rates and timing, types of fertilizer materials, how to read a fertilizer label and how to avoid turf damage and environmental pollution.

Fertilizing Your Garden - This publication will help you ensure that your plants receive ample levels of all nutrients for optimum yield, quality, and aesthetic value.

Organic Fertilizer Resources

Estimating Plant-Available Nitrogen from Manure - Estimating plant-available nitrogen provided by manure. This publication is primarily designed for use by agricultural professionals that assist farmers with nutrient management. The focus is primarily on cropping systems west of the Cascades in Oregon and Washington.

Fertilizing with Manure - This publication is designed for the small to mid-sized crop producer to assist the producer in more efficiently managing nutrients from solid animal manures. The purpose of this publication is to describe how to determine the appropriate manure application rate based on the type of manure and crops, and describe how to apply the manure at that rate.

Manure Management Practices to Reduce Water Pollution - Allowing manure to flow into surface water causes pollution. Most pollution results when the manure comes in contact with runoff or surface water. There are basic practices that keep manure away from runoff and surface water.

Fertilizing with Yard Trimmings - Yard trimmings are a mixture of grass clippings, leaves, woody trimmings, weeds, and soil. Most yard trimmings are a beneficial soil amendment because they are a good source of plant nutrients and organic matter.

Predicting Nitrogen Availability for Organic Amendments - A study to improve the ability to predict nitrogen availability from organic soil amendments, including improved accuracy of Nitrogen availability estimates, to target amendment application rates to meet crop N needs.

Soil Fertility in Organic Systems: A Guide for Gardeners and Small Acreage Farmers - Plant growth is affected by numerous factors, including climate, pest pressure, and nutrient availability. As plants grow, they rely on their roots to provide structural support, water, and nutrients. The right nutrients are essential for growing healthy, productive plants. Well–managed, fertile soils can supply plants with all the nutrients they need. 

Organic Fertilizer & Cover Crop Calculator -Oregon State University Extension developed the Organic Fertilizer and Cover Crop Calculator. This tool allows farmers to estimate plant-available nitrogen (PAN) provided by organic fertilizers and cover crops, prepare balanced fertilizer programs that account for cover crop N, and compare the costs of different fertilizer programs and cover crops.

Fertilizers and the Environment

Nitrates and Groundwater: Why should we be concerned with our current fertilizer practices? - This publication describes the challenges faced by the western Oregon grower concerning NO3 - leaching losses to shallow groundwater aquifers. This paper describes the conditions that make western Oregon a particularly vulnerable environment to NO3; the incentives for western Oregon growers to undertake a careful nutrient management plan; and the options for best management practices (BMP’s) available to growers.

Manure Management for Small Farm Livestock Operations: Protecting surface and groundwater - This publication is going to discuss manure as a pollution source, how its constituents can contaminate surface and groundwater, and what practices can help prevent pollution. Best management practices (BMPs) that can help you protect water quality and maintain your farm’s productivity are outlined. Additional sources of information and assistance also are listed.

Tree Buffers Along Streams on Western Oregon Farmland - Stream conditions depend in part on the vegetation in the riparian zone near the water. This publication explores a variety of options, mindful of trade-offs between farmland production and fisheries and wildlife values.

Irrigation Water Quality Fertilizer Guide - Most irrigation water in Oregon is of excellent quality. Occasionally a deep well yields water that is too salty for irrigation, or contains constituents that are detrimental to plants or soils.