The Forest and the Beacon of Baker Island: Topography, Tree Height, and Tree Growth: Initial Forest Resource Inventory of Baker Island, Acadia National Park

Gilmore, Daniel; Kimball, Alan; Morin, J.

'The beacon of the Baker Island lighthouse is increasingly obstructed by the growth of the island's spruce forest. Forestry students from the University of Maine measured the topography and timber resources of the island in May of 1992'. 'The spruce stands on Baker Island appear to be even-aged and of good health and vigor. Two broad site categories were identified: poor sites having trees less than 40 feet in height, and better sites having trees greater than or equal to 40 feet in height. Height growth data obtained from cross sections cut at 4 foot intervals from 4 felled trees (2 trees from each site category) were compared to published site index curves. A substantial increase in the rate of height growth after 1992 appears unlikely due to the age of the trees, the harsh maritime climate, the shallow soils, and the low site index of Baker Island. The curve depicting total height over time for the 2 trees taken from good sites, however, shows that total height has not yet reached a plateau. Per acre volume estimates were determined using timber cruise data and volume-basal area ratios. Limited time and a lack of current aerial photos precluded an overall volume estimate. Tree heights and ground elevations at 50 foot intervals along 8 transects extending from the lighthouse to the shore were graphed and used to evaluate management alternatives. Management alternatives included: 1) implementing the US Coast Guard's proposal of using lighted marine buoys, 2) raising the level of the light to make it more visible from the sea, and 3) developing a resource management plan based on the periodic removal of trees obstructing the view of the light from the sea. Both of the latter proposals included a recommendations to sector the northern portion of the lighthouse beacon red to warn mariners of the shoals between Baker Island and Cranberry Isle.' /STUDY LOCATIONS:/ /ISLANDS/Baker Island/