The construction of platforms and bridges for forest canopy access.

Lowman, M.D. and B. Bouricius.
Page Range: 
canopy, modular construction, platform, walkways
A modular construction system of bridges and platforms has been designed to facilitate access into forest canopies. This technique creates permanent sites at moderate cost for long term observations and data collection, and allows collaborative research by a group of researchers within one region. Walkways have been constructed in both temperate and tropical forest ecosystems. The approximate costs, safety concerns, and construction specifications are described for two sites: one in subtropical rain forests of Belize, Central America, and one in a temperate deciduous forest at Millbrook, New York. Research in forest canopies has been limited by logistic constraints of access (reviewed in Mitchell 1982, Lowman and Moffett 1993, Moffett and Lowman 1995). Over the past decade, several inexpensive techniques have been developed, but they usually are restricted to solo efforts. These include single rope techniques (Perry 1978, Lowman 1984, Nadkarni 1984); ladders (Selman and Lowman 1983, Gunatilleke et. al. 1994); and towers (Odum and Ruiz-Reyes 1971, Zotz 1994). Devices that facilitate research by a group of scientists simultaneously have also been developed, but usually are considerably more expensive (e.g. the raft and dirigible (Hallé and Blanc 1991)), construction cranes (Parker et al 1992)). In essence, there appears to be a distinct correlation between expense of access method and number of scientists that can safely utilize a common device (see Table 1 in Moffett and Lowman 1995).