Title: THE EFFECT OF FERTILIZER TREATMENTS ON OIL CONTENT AND NUTRIENT CONCENTRATION OF PEPPERMINT IN WESTERN OREGON Abstract approved Redacted for Privacy

During the summer of 1967 a fertilizer survey was conducted to determine the nutrient status of peppermint fields, the nutrient concentration of plant tissue and the oil content of peppermint in Oregon. Plant and soil samples and the field's fertilizer history were collected from cooperators in Oregon's peppermint growing areas in June. Oil samples and plant samples were collected in August and September. Results of the survey indicated the following: (1) Micronutrient levels of the plant tissue were relatively high and the highest Mn concentrations were associated with lower oil concentrations. (2) The highest levels of total nitrogen in the leaf analyses were associated with lower oil concentrations. The higher N levels appeared to be related to fields with rank stemmy growth. (3) All P levels were quite high and there were no apparen