Donald Arthur Horneck

Evaluation of potato production best management practices

A 2001 survey indicated that many growers are reluctant to adopt research-based recommendations because of a perception that it is not practical or applicable to their specific farming operation. Other growers, however, appear to adopt these practices successfully. Highlighting “model” growers is a method that can be used to field-test research findings and facilitate grower adoption. The objectives of this project were to: 1) establish field demonstrations with potato (Solariumtuberosum L.) growers who generally follow researchbased best management practices (BMPs); 2) establish plots within each field to compare BMPs with a high input, maximum yield management (MYM) approach; and 3) enhance grower confidence regarding researchbased BMPs. Fourteen field trials were conducted in the Pacific Northwest during 2002-2005. Five replicates of BMP and MYM plots were established in each field. The BMPs consisted of sampling, scouting, and use of prediction models to aid in determining rate and timing of inputs to maximize returns. In contrast, the MYM approach was based on tradition and calendar timing, with a near zero tolerance for pest and nutrient limitations. The MYM plots had 1.7 to 13.2% more fertilizer and pesticide costs than the BMP plots. The MYM treatments resulted in significant marketable yield increases in three fields and decreases in two fields, with the remaining nine fields and the combined average of all 14 fields being statistically equivalent. When factoring in estimated costs, only two fields resulted in a monetary advantage with MYM treatment. In contrast, the BMP treatment resulted in significant increases in net crop value in five fields, as well as the combined average of all 14 fields (

Improving Phosphorus Use Efficiency Through Potato Rhizosphere Modification and Extension

200 ha-1 or 3.2%). These field demonstrations, along with associated field days and grower meetings, have resulted in many documented changes in grower practices towards BMPs, with many more undocumented changes probable.ResumenUn estudio que se hizo el 2001 indica que muchos agricultores son renuentes a adoptar las recomendaciones basadas en la investigación, debido a una percepción poco práctica o aplicable a sus operaciones de cultivo. Otros, sin embargo, parecen adoptar exitosamente estas prácticas. El destacar a los agricultores “modelo” es un método que pude ser usado para probar en el campo los resultados de la investigación y facilitar su adopción. Los objetivos de este proyecto fueron: 1) hacer demostraciones de campo con los agricultores que cultivan papa (Solarium tuberosum L.) que emplean generalmente las mejores prácticas de mane jo (BMPs) basadas en investigación; 2) establecimiento de parcelas dentro de cada campo las BMPs con gastos altos, un enfoque de manejo máximo de rendimiento (MYM); 3) incremento de la confianza del agricultor referida a los BMPs basados en investigación. Catorce pruebas de campo se realizaron el Pacñfico Nor Occidental durante 2002-2005. Cinco repeticiones de BMP y de MYM se hicieron por parcela en cada campo. Los BMPs consistieron de muestreos, exploración y uso de modelos de predicción para ayudar a determinar la tasa y registro de gastos para alcanzar el máximo de ganancia. Contrariamente, el enfoque MYM estuvo basado en la tradición y distributión del tiempo, con tolerancia cero para problemas de pestes y nutrientes. Las parcelas MYM recibieron 1.7 a 13.2% de gastos en fertilizantes y pesticidas que las parcelas BMP. Los tratamientos resultaron en aumento significativo de rendimiento comerciable en tres campos disminución con los restantes nueve y el promedio combinado de los 14 campos estadñsticamente equivalentes. Cuando se factorizó en gastos estimados, sólo dos campos resultaron en ventaja monetaria con el tratamiento MYM. Contrariamente, el tratamiento BMP dio como resultado un incremento significativo en cinco campos, asñ como el promedio combinado de todos los 14 campos (

Needle Collection Time for Nutrient Evaluation in Christmas Tree Production

200 ha-1 o 3.2%). Estas demostraciones de campo, junto con los asociados dñas de campo y reuniones de agricultores, han dado como resultado muchos cambios documentados en el proceder de los agricultores hacia los BMPs, con cambios probables no documentados.

Ground Beetle (Coleoptera: Carabidae) Populations in Commercial Organic and Conventional Potato Production

Phosphorus (P) fertilization is essential for societal sustainability. However, plant P uptake is inefficient due to poor soil P solubility, especially for the potato (Solanum tuberosum L.) plant due to its relatively poor rooting efficiency. Phosphorus use efficiency (PUE) can be increased with rhizosphere modifications such as: (1) raising the bulk pH of acid soils, (2) placement of fertilizer in the rhizosphere by broadcast incorporation and/or, especially, as a concentrated band, (3) use of slow and controlled release P fertilizers, (4) use of organic acids to increase P solubility in alkaline soils, (5) use of an acid polymer, and (6) extending the effective rhizosphere zone via any practice that fosters root growth, such as through promotion of mycorrhizal development. Alone or in combination, these techniques offer an opportunity to increase PUE.ResumenLa fertilización con fósforo (P) es esencial para la sustentabilidad social. No obstante, la absorción de P por la planta es ineficiente debido a la pobre solubilidad del P en el suelo, especialmente para la planta de papa (Solanum tuberosum L.) debido a su relativamente pobre eficiencia radical. Se puede incrementar la eficiencia del uso del fósforo (PUE) con modificaciones a la rhizosfera, tales como: (1) aumentando el pH masivo de suelos ácidos, (2) colocando al fertilizante en la rhizosfera mediante incorporación amplia y/o, especialmente, en banda concentrada, (3) uso de liberación lenta y controlada de fertilizantes fosforados, (4) uso de ácidos orgánicos para aumentar la solubilidad del P en suelos alcalinos, (5) uso de un polímero ácido, y (6) expandiendo la zona efectiva de la rhizosfera por vía de cualquier práctica que estimule el crecimiento de la raíz, como mediante la promoción del desarrollo micorrízico. Solas o en combinación, estas técnicas ofrecen una oportunidad para aumentar la PUE.

Soil test interpretation guide

Christmas tree needle sampling to evaluate nutrient need is an established practice. Data to support the recommended fall sampling time in Oregon and Washington were not found. In addition, the recommendation for needle sampling of Fraser fir in North Carolina was made without data from winter months. The goal for this article is to affirm or modify recommended needle sampling time. Needles of Douglas fir, Turkish fir, Nordmann fir, Noble fir, Grand fir, and Fraser fir Christmas trees were collected monthly for a year, dried, and analyzed for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and boron (B). No single period was found for any species when needle nutrient concentration was stable for all elements determined. Needle collection time was chosen by integrating cultural practices, likelihood of nutrient deficiency, and needle nutrient concentration changes for species grown in an area. Needle collection is recommended during February in western Oregon and Washington. The current sampling time, fall, is logical for Fraser fir Christmas tree production in North Carolina.

Methods of soil analysis used in the Soil Testing Laboratory at Oregon State University

Abstract In 2 consecutive years, ground beetles (Coleoptera: Carabidae) were sampled in commercial organic and conventional potato fields, using pit fall traps. Four conventional and 3 organic potato fields were surveyed to determine ground beetle taxa composition. In a related study, potato fields were assigned to 1 of 4 transitional systems to include: organic, no spray (usually referred to as no control and/or only OMRI certified control), IPM-conventional (directed control, after sampling) and conventional (broad spectrum pesticides) systems. Seven taxa of ground beetles were identified: Anisodactylus kerbyi Lindroth 1953, Amara sp., Bembidion sp., Calosoma cancellatum Eschscholtz 1833, Calathus ruficollis Casey 1920, Calathus ingratus Dejean 1828, and Pterostichus adstrictus Eschscholtz 1823. With the exception of C. cancellatum, which was not identified from organic fields in the first yr of this study, all taxa were collected in both organic and conventional potato fields both yr. Based on total number of specimens collected, Bembidion sp., P. adstrictus and Amara sp. represented 42.8% of the total specimens collected. The smallest number of ground beetles was collected from no spray and IPM-conventional systems. This study provides basic valuable information regarding beetles populations for growers making transition from conventional to organic potato production.