Cost Benefit Analysis of Planting Stock – a Three-Year Study

Cost Benefit Analysis of Planting Stock – a Three-Year Study

Monica Randazzo
Undergraduate Research Assistant
University of Minnesota, Department of Forest Resources

What information do city foresters and managers need in order to effectively and efficiently increase their urban forest canopies? A comprehensive answer to this question is multi-faceted, as urban forests are dynamic systems with a variety of complex inputs and outputs. The Cost Benefit Study of Planting Stock aims to address a small component to this larger question by asking another: are there significant differences in growth rates and survival during the establishment period (3 years) among trees of different stock types? This study tracks the growth rate and survival of trees that are either: containerized, balled and burlapped, spring-planted bare rooted, and fall planted gravel bed bare root. This study functions as a method of providing physical evidence regarding the success of trees in the establishment period. Certain stock types may be better suited for different plantings based on a variety of factors, and this study seeks to help communities make well-informed tree planting decisions.

This study looks at trees across nine communities in Southeastern Minnesota: Fridley, Robbinsdale, North St. Paul, St. Paul, Shakopee, Rochester, Arlington, New Ulm, and St. James. All trees planted in 2016 from each community are included, except for in Rochester, Fridley, and St. Paul, which have smaller samples of the total planted trees. In Rochester and Fridley, study trees are included based on the amount of information available, primarily by the accuracy of location on maps created during plantings. Trees without clear and sufficient data (planting stock, species, or location) were not included. The City of Saint Paul planted more trees than UFORE investigators were able to sample in a single year, so the total population was stratified by planting stock type, with up to one-hundred trees randomly selected from each stratum.

Each study tree has a unique ID number, and a caliper measurement (diameter) taken at six inches above the ground at the end of the growing season. Every tree will have caliper measurements taken for three years following planting. Mapping location of study trees is done using Arc GIS.  Measurements and monitoring of trees planting in 2017 and successive years will occur in the same manner; each study tree is included for three years after the planting date as in the 2016 data set.