Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Plants, Soils, and Climate

Committee Chair(s)

Grant E. Cardon


Grant E. Cardon


Brent L. Black


Paul R. Grossl


Nutrient concentrations in plant tissues are directly correlated with the nutritional status and productivity of fruit trees. Plant tissue testing is one of the most effective and accurate methods to determine nutritional status of perennial plants. Tissue test analyses were performed on tart cherry (Prunus cerasus) and peach (Prunus persica) leaves to validate tissue sufficiency levels used in Utah and to determine optimal timing of tissue sampling for prediction of harvest nutrient status, focusing on phosphorus (P), potassium (K), calcium (Ca), iron (Fe), and zinc (Zn). Sufficiency limits that were adopted in Utah were developed in the 1960s from research data accumulated from the primary fruit growing regions in the United States. Limited research has been conducted under Utah growing conditions. Tissue nutrient concentrations over time correlated well with current sufficiency limits and observed nutrient deficiencies in the field. Tissue concentrations of P, K, Fe, and Zn were found to be chronically low in Utah orchards. Plant tissue data demonstrates that mid-season sampling can predict nutrient status at harvest. Mid-season sampling also allows time for corrective adjustments to maintain sufficiency levels and reach optimal fruit production. Nutrient management practices are commonly applied annually to increase yield, fruit quality, and overall health of an orchard. Yield was measured on previously treated tart cherry orchards to determine residual effect on tree nutrient status. Orchards were treated 2 to 3 years prior with rate-response formulations of P and K; one has since adopted recommended fertilizer rates for optimizing tart cherry production in Utah and the other continued with their less aggressive management practices. The less aggressively managed orchard showed trends across treatments, but differences were not significant. Annual fertilizer applications may not immediately show effect during year of application, but long term management is essential for overall productivity of orchards.