This study represents an internship, as a requirement of the Professional Science Masters program at Oregon State University, performed with Western Ag Innovations Inc. The study consisted of two aspects -- one business and one science oriented. The two objectives of this internship were to: 1) qualitatively evaluate how two...
Phytophthora cinnamomi is a soilborne pathogen that causes root rot disease of highbush blueberry (Vaccinium corymbosum L.). When new installations of susceptible blueberry cultivars are infected with P. cinnamomi, plants often fail to grow significant new tissue, greatly reducing yields over the life of the planting. Chemical fungicides are available...
Highbush blueberry (Vaccinium corymbosum L.) is adapted to soils with high organic matter and acidic pH. Composts provide organic matter and nutrients for growing blueberry in mineral soils, but many composts are high in pH and soluble salts. Acidification with elemental sulfur (S°) can remedy high pH, but the process...
In order to properly utilize organic amendments as nitrogen sources, reliable methods
to estimate plant-available nitrogen (PAN) are needed. The objectives of this study
were to (1) evaluate the use of crop and soil responses in fertilizer N equivalence
(FNE) calculations, (2) examine the relationships between the C/N ratio, total...
Quantifying labile phosphorus (P) pools in biosolids is needed to manage biosolids for both agronomic and environmental purposes. Phosphorus indices originated in an effort to protect surface water quality from-non-point-agricultural P inputs. The objectives of this research were to: (1) evaluate soil test components of the western Oregon P index...
Estimates of nitrogen (N) available from long-term application of organic
amendments are required to balance N inputs with crop N requirements. Two studies
were conducted to (1) determine N mineralized from organic amendments (manures
and composts) during year 2 after application, and (2) compare plant-available N
(PAN) determined via in...
It is widely accepted among nursery producers that [Pseudotsuga menziesii (Mirbel) Franco] bark (DFB) is an excellent substrate for container production, hence its widespread use in Oregon and other regions where Douglas fir constitutes a significant portion of the forest products industry. Despite its widespread use, little information is available...
Compost maturity is an important determinant of end use for composted municipal yard debris, and generally refers to the effect the compost has on plants. The rate of microbial respiration is an indicator of compost stability. The objectives of this research were to: i) determine whether continuous aeration resulted in...
