Relationships among wetland indicators in Hawaiian rain forest

We applied established methods for wetland identification in lowland and montane wet forests (rain forests) on the island of Hawaii to determine whether rain forests exhibited wetland indicators specified in delineation manuals and to examine relationships among indicators of hydrophytic vegetation, hydric soils, and wetland hydrology. Morphological characteristics and ferrous iron tests indicated pockets of hydric organic soils within areas mapped as Folists. Hydrophytic vegetation decisions based on prevalence values agreed with hydric soil determinations more often than did decisions based on dominant plant species. None of the rain forest types we studied exhibited wetland indicators throughout, but some sites contained scattered small wetlands occupying microtopographic lows created by cracks, folds, and undulating flow patterns in the lava bedrock. Further work is needed to identify reliable wetland indicators that can be used during drier portions of the year and to distinguish hydric from nonhydric organic rain forest soils.