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DRAFT 9 <br /> Willamette basin, urbanization, land use practices, and fire suppression have altered the <br /> historic processes that maintained native grasslands. <br /> Flood control has also affected L. bradshawii by reducing available habitat and, possibly, <br /> seed dispersal. Flood control reduced the amount of seasonally wet prairies throughout <br /> the Willamette Valley. Since L. bradshawii is dependent on wet areas, often within the <br /> floodplain of a creek or small river, hydrologic changes have drastically reduced habitat <br /> available to the plant. L. bradshawii seeds have also been found to have some buoyancy, <br /> k and dispersal may <br /> P be increased by flooding (USFWS 1993). If dispersal is enhanced by <br /> flooding, it is likely that the hydrologic changes have reduced dispersal quantity and <br /> \\ <br /> distance. <br /> Most of the habitat for L. bradshawii occurs in and around Eugene and Corvallis, Oregon <br /> (USFWS 1993). Any undeveloped, flat grasslands which may contain L. bradshawii and <br /> other native wet prairie species are often primary targets for urban development. <br /> In addition to habitat alterations, disease may also be influencing L. bradshawii, <br /> particularly the smaller populations. A fungus that causes a brown spot disease occurs <br /> sporadically within a population, destroying the aboveground portions of the plants. <br /> Aphids and spittle bugs also parasitize L. bradshawii. These parasites were found <br /> exclusively on plants with seeds (Kagan 1980). The seed on fungus- infected plants <br />