The giant reed invasion is of immediate concern in the Russian River watershed. Based on information from river systems in southern California and other riparian areas throughout the world, it is clear that giant reed may be one of the most serious impacts to the remaining riparian habitat in the Russian River system, having a direct impact on the salmonid fishery. Given the fact that the Russian River watershed is home to federally listed salmonid species - steelhead trout, coho and chinook salmon - as well as the federally listed freshwater shrimp and red legged frog, it is imperative that riparian zone management in these ecosystems take into account the impacts of invasive plants. Preservation of the remaining riparian habitat, as well as restoration of fisheries resources, will be more successful, and far more cost effective, if the giant reed issue is addressed during the early phase of this invasion.
USGS Digital Orthogonal Quarter Quadrangles (DOQQ) were used as base maps for the project, for the raster-format underlay for display of the final mapped stands of Arundo, as well as for the calibration of the unrectified low-level Aggregate Resources Management (ARM) Plan aerial photos available for the Alexander Valley, Middle and part of the Fitch Mountain reaches. Arundo feature boundaries and location were 'heads-up' digitized onto USGS DOQQ base maps using ESRI ArcView 3.1 software, for the Mendocino County Reach, Lower Reach and part of the Fitch Mountain Reach in Sonoma County. Identification of giant reed stands was enhanced using sequential low-level oblique aerial photographs taken by CRP staff in January and February, 1999.
In the fall/winter months of 1998, low-level fixed wing aircraft test flights were conducted to determine the best film type, weather conditions, season, photo angle, and plane flight altitude for photographing Arundo in a riparian setting. Both banks of the 115 mile long Russian River mainstem were photographed during several low level flights conducted during the winter months (Jan./Feb. 1999), when riparian plant species were dormant, providing the clearest view of Arundo stands. Attempts were taken to photograph during overcast weather to avoid shadow effect. A series of sequential, overlapping photographs was taken for both banks, at an approximate altitude of 500 feet, at a 45 degree angle, using Kodak Gold color film.