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5 <br /> In addition to habitat alterations, disease may be influencing Bradshaw's lomatium, <br /> particularly smaller populations. A fungus that causes a brown spot disease occurs <br /> sporadically, destroying aboveground portions of the plants. Seeds on fungus- infected <br /> plants seldom reached maturity before the plants died back. Aphids and spittle bugs also <br /> parasitize Bradshaw's lomatium. Parasites were found exclusively on plants with seeds <br /> (Kagan 1980). Parasitized plants had a significantly higher incidence of aborted fruits. <br /> Parasitization and resulting fruit abortion can severely reduce the size of, or eliminate a <br /> population. <br /> Habitat conditions and environmental stressors, such as drought and parasitism, may limit <br /> the survival and recovery of Bradshaw's lomatium populations. All currently known sites <br /> are relatively disjunct, separated by agricultural or urban development, substantial <br /> distance, and /or topography. Most sites also have relatively few plants and/or are small in <br /> area. The results of such habitat fragmentation (i.e., isolation, low seed dispersal, and <br /> reduced numbers of pollinators) may combine with other factors (i.e., disease or <br /> parasitism) to further threaten Bradshaw's lomatium. <br /> Site specific <br /> The conservation area is primarily used for recreational purposes. Therefore, past <br /> management of the conservation area has focused on recreational uses. Grassy areas, <br /> including wet prairie habitat, are often mowed. Mowing may have both beneficial and <br /> adverse affects on Bradshaw's lomatium and other native plants. Although regular <br /> mowing may prevent succession, native grasses and forbs may be adversely affected <br /> when mowing is conducted before seeds have set in late summer. At times, early mowing <br /> may have reduced seed production in the Upper Amazon Basin. <br /> Vehicle and pedestrian traffic may adversely affect Bradshaw's lomatium in the <br /> conservation area. Damage may be most substantial after flowers have formed but <br /> before seeds have matured. Impacts of this type have been noted in Amazon Park. For <br /> example, population impacts and habitat fragmentation from construction of Amazon <br /> Parkway may have caused loss of individuals but the extent of impacts are not known <br /> because of the lack of complete surveys at the time. Public education may also increase <br /> awareness of the plant and its habitat within the Upper Amazon Basin. <br /> As previously described, isolation and cumulative loss of habitat continue to threaten <br /> Bradshaw's lomatium. The Recovery Plan identifies tasks necessary to downlist the <br /> plant. Several of these tasks relate to establishment of management areas within four <br /> identified recovery areas: North Central Willamette Valley, Central Willamette Valley, <br /> Southeastern Willamette Valley, and West Eugene. Within these four areas and using <br /> information on extant locations, ownership, and willing landowners, ten management <br /> areas were to be selected. Four lie within the West Eugene Area, which encompasses the <br /> 97 -0 0401 <br />