Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Agricultural Systems Technology and Education

Committee Chair(s)

Jay C. Andersen


Jay C. Andersen


The major purpose of this study is to analyze the economic feasibility of bloom delay by sprinkling as a means of protecting delicious apples from frost. The framework of this study is based on decision making theory under uncertainty. It demonstrates the usefulness of the Bayesian approach to determine optimum action to take in face of uncertain climatic conditions. The economic analysis was conducted for Farmington, Utah, where significant relationships were found between the end of winter rest (end of chill-unit accumulation) and time of full bloom of red delicious apples.

A posteriori probabilities for the state of nature were determined using accumulated data of end of winter rest of the apple trees. Applying the Bayesian approach, optimal strategies were determined by use of a posteriori probabilities and knowledge of time of end of winter rest.

It was concluded from the analysis that the installation of solid set sprinklers and use of sprinkling to delay bloom is an effective means of frost protection. Sprinkling provides two methods of freeze protection. Bud development can be delayed increasing the hardiness of the bud to colder temperatures. Sprinkling can also be used during periods of freezing temperatures to protect the buds from freezing. It was found that a combination of protection by delay and by sprinkling for freeze protection would result in increased net returns over any other alternative. An important finding of this study is that with the dual protection afforded by sprinkling, extended amounts of delay are not necessary to obtain the desired results.