Department of Environmental Studies
This study examines the structure and age, and investigates the land use history of the Atlantic white cedar (Chamaecyparis thyoides) stands in Appleton Bog, Knox County, Maine. Three objectives were to determine whether these present stands of mature cedar are similar in structure and age, how long they have been established at this site, and what disturbance or disturbances led to their establishment and development. Nineteen four-meter radius circular plots were located throughout the three Atlantic white cedar stands at a 200-meter spacing. The species, diameter at breast height (dbh), and crown classification were recorded for all trees within the plot greater than five centimeters dbh. In addition, the age of each tree was determined by taking an increment core within 30 centimeters of the base. At two locations in each plot the surface organic layer, to a depth of ten centimeters, was visually examined for evidence of charcoal. Finally, information pertaining to the 19th century history of Appleton Bog and the surrounding area was researched through an examination of historic maps, deeds, census results, newspapers, and other documents. A total of 241 live trees were within the research plots. Of these, 206 (85.5%) were Atlantic white cedar. Average stand density for all trees ranged from 2,438 trees per hectare to 2,577 trees per hectare. For cedar the range was 1,692 trees per hectare to 2,239 trees per hectare. The average basal area in each stand varied from 86 to 98 m2/ha. Cedar made up a significant proportion (up to 94%) of this basal area. ANOVA testing revealed no significant difference in density, basal area, and diameter at breast height between the three stands for all tree species and for only cedar. The Atlantic white cedar trees occur in even-aged stands with a mean age of 118 years (SD = 10 years). 85% of the cedar trees are between the ages of 105 and 130 years. This information suggests that a large scale disturbance occurred at this site circa 1865. Deed and census records indicate that cedar was present in Appleton Bog during the 19th century and was an important commercial species during that time. Historical records and field observations suggest that commercial harvesting of the cedar, which began circa 1850 and continued until approximately 1870, was the disturbance that led to the present stands. Future active management of this site may need to be considered if pure, dense stands of cedar are to continue to exist hundreds of years form now. Additional research, addressing the historic role of fire and the paleohistory of the cedar, is necessary to understand this site’s natural disturbance regime and further guide any management decisions.