College of Agricultural Sciences

Introduction

Vegetable growers in the Willamette Valley use high rates of nitrogen fertilizers, often exceeding 250 to 300 pounds actual N/acre per season. While growers believe that these rates are necessary to achieve maximum yields and quality, a considerable portion of the applied fertilizer is not taken up by the crop. This has raised concerns that the remaining N may be contributing to nitrate pollution of groundwater. Improved efficiency of nitrogen management may be possible if the fertilizer could be placed for maximum contact with the root system.

Research report from OSU's North Willamette Research and Extension Center

Delbert Hemphill
OSU Dept of Horticulture

Mary Powelson
OSU Dept of Botany and Plant Pathology

Introduction

Introduction

Research report from OSU's North Willamette Research and Extension Center

Delbert Hemphill
OSU Dept of Horticulture, NWREC

John Selker
OSU Dept of Biological and Ecological Engineering

Richard Dick
OSU Dept of Crop and Soil Science

Introduction

Introduction

Introduction

North Willamette Research and Extension Center report

Delbert Hemphill
OSU Dept. of Horticulture

Dan McGrath
OSU Dept. of Horticulture

Introduction

Introduction

* Green beans tested for yield and quality * Muskmelons tested at Medford