Growth strategies of main trees and forest architecture of a Fagus-Magnolia forest in Florida, USA
Abstract
Growth strategies of six species of trees are compared and used to analyze forest architecture. They included the overstory species Fagus grandifolia, Magnolia grandiflora, Pinus glabra and Liquidambar styraciflua, and the understory species Ostrya virginiana and Ilex opaca. The six species were abundant in Woodyard Hammock, an old-growth forest in northern Florida, USA. Height, stem diameter, crown projection and radial growth were measured in trees between 5 and 35 m tall. Three different, but non-exclusive, growth strategies were identified for the tree species: 'survival' (Fagus grandifolia, Magnolia grandiflora, Ilex opaca), 'occupy open space' (Fagus grandifolia, Ostrya virginiana, Ilex opaca), and 'reach above competitors' (Liquidambar styraciflua, Pinus glabra). In two transects (0.42 ha) and one quadrat (1 ha), heights of dominant trees were used to distinguish different phases of forest development, which were mapped. In the quadrat, juvenile canopy trees in the undergrowth were mapped. The combination of presence of different developmental phases, presence of juveniles in the undergrowth, growth strategies of main tree species, and disturbance regime was used to assess forest development in the near future. Fagus grandifolia is predicted to become the main dominant species, but the frequent hurricanes open the forest canopy and provide opportunities for understory species (Ostrya virginiana and Ilex opaca), and light-demanding overstory species (Liquidambar styraciflua and Pinus glabra). © 1996 Kluwer Academic Publishers.