american samoa - University of Hawaii at Manoa Botany Department

VEGETATIONNovember 1999 SurveyArt Whistler of Isle Botanica conducted a botanical survey of the lower Sauino Stream segmenton November 5, 1999. Mr. Whistler was part of a three-person field survey team organized byPedersen Planning Consultants that observed wetland vegetation, habitat for aquatic fish andinvertebrates, stream hydrology, as well as land uses within and adjacent to the wetland. Hisobservations are summarized in the following paragraphs.The vegetation along the 600-foot Sauino Streamdiffers considerably between the north and southsides of the stream channel.Vegetation along the south side of the channelcontained maintained grasses such as vaolima(T-grass) and Kyllinga brevifolia. Lesseramounts of carpet grass (Axonopus compressus),Alternanthera sessilis, and Kyllinga nemoralis.A smaller banana plantation was also adjacent tothe south side of the channel. None of the grassor tree species were obligate or facultativewetland plants.The north side of the stream channel resembled more of a wetland environment. This area wasdominated by California grass, Job’s tears, T-grass, and Merremia umbellata. Job’s tears andCalifornia grass are both facultative wetland species.Vegetation TrendsPrior studies of the vegetation of along lower Sauino Stream were conducted by BiosystemsAnalysis, Inc. A brief mention was made of a “hummocky area” between South PacificTraders (now Laufou Shopping Center) and Lion’s Park.Within a species checklist, botanists noted that the “hummocky area” was dominated primarilyby vaolima (T-grass) and Merremia umbellata. Drier margins were dominated by beggar’s-tick(Bidens alba) and a sensitive plant vao fefe (Mimosa pindica). No meaningful correlation canbe made concerning historical vegetative trends since the more general location of the“hummocky area” is not comparable to the more specific stream segment along Sauino Stream.However, it is interesting to note that both vaolima (T-grass) and Merremia umbellata wereidentified by both surveys.In the absence of other plantings, the continued maintenance of grasses along the south side ofthe 600-foot stream segment will likely maintain the presence of existing grasses. The northside of the channel may also continue to support California grass and Job’s tears unless bananaplantations are established. Residential expansion is not expected in light of the flood potentialin the vicinity of the stream segment.American Samoa Wetlands/Streams Restoration and Enhancement PlanFebruary 2001, Sauino Stream, Page 8-5