Evergreen Tree Species for Urban Use in Eastern Tennessee

The objective of this study was to determine which of five tree species was best suited for urban conditions in eastern Tennessee with respect to certain criteria. The species included eastern white pine (Pinus strobus L.), eastern hemlock [Tsuga canadensis (L.) Carr.], Norway spruce [Picea abies (L.) Karst.], southern magnolia (Magnolia grandiflora L.), and eastern red-cedar (Juniperus virginiana L.). The criteria used for comparing the species were resistance to disease, resistance to insect pests, range of soil fertility adaptability, range of soil pH adaptability, and aesthetic appeal.

Questionnaires were sent to nurserymen and landscape architects in Tennessee and adjacent states to determine the importance rating of each criteria on a scale of 0 to 10. Questionnaires were sent to Tennessee nurserymen and landscape architects, ornamental horticulturists, plant pathologists, entomologist, and soil scientists, to determine the rating of each species on a scale of 1 to 5, with respect to all criteria except aesthetic appeal. Aesthetic appeal was determined by interviewing 500 people, using photographs. They were rated on a scale of 1 to 5. Data were evaluated by quantitative ranking, where the species and criteria importance ratings were used to arrive at a species "score." The species with the highest score was deemed most suitable for urban planting in eastern Tennessee.

Southern magnolia was determined the most suitable tree for urban conditions in Knoxville, Tennessee.