Ordinance No. 20513 - Laserfiche WebLink

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Plectritis congesta Potentilla gracilis Prunella vulgaris ssp. lanceolata Ranunculus occidentalis Sidalcea malv flora var. virgata Sisyrinchium idahoense Solidago canadensis Symphyotrichum hallii Symphyotrichum subspicatum Triteleia hyacinthina Viola adunca Wyethia angustifolia Grass and sedge species could include: Carex tumulicola Danthonia californica Elymus glaucus Festuca roemeri Koeleria macrantha Plant Community Establishment and Management The Riverfront Property currently owned by EWEB will be a challenging site to restore in many respects. It is essential to recognize that native plantings, like any garden, need care. The need to establish plants in the sometimes - difficult conditions of steep banks and riprap present particular challenges. Furthermore, once the plantings are established, regular and knowledgeable management is needed to maintain native plantings in the face of continued invasion by non - native introduced species, and in light of the need to maintain high levels of native species diversity to fulfill desired ecological functions. For these reasons, both a carefully conceived implementation plan, and a clear ongoing management plan that combines horticultural practices with ecological restoration practices, are imperative. The presence of riprap and steep banks along much of the Riparian Zone will make it difficult to plant and maintain native species over time. In appropriate areas along the river's edge, willow wands can be inserted at least 4' into the bank to prevent them from washing away in high water prior to root development. There are also some areas of low riparian bench that hopefully have accumulated enough soil to allow for normal planting of appropriate native trees, shrubs and herbaceous plants. For tree and shrub planting on the midslope banks that are not slated to be altered, the creation of small gaps in the riprap and adding soil to these gaps is one way that planted trees and shrubs might be established. In addition, introducing native species using seed instead of nursery -grown stock should be considered, since seedlings may have a better chance of establishing in difficult conditions than ones raised in a nursery or greenhouse and transplanted to the site. One caveat to the approach of moving riprap and importing soil would be the potential weakening of the riprap through removal of some material. For this reason, consultation with U.S. Army Corps of Engineers would be advised. It is possible that simply adding soil into naturally occurring dips and crevices in the riprap without removal of any rocks would work, although it might be harder to prevent the soil from washing away. The portion of the Midbank area that is above the Ordinary High Water Mark will have a better chance of establishment in this regard. In addition to the challenges inherent in plant establishment, irrigation of all new plants will be required for at least two years after planting. This will be difficult due to the steepness of the banks, which will cause water to run downhill instead of soaking into the ground, and the presence of the riprap, which will make traveling across the area to each plant on foot difficult and sometimes hazardous. In the areas where it has been proposed to remove the riprap and lower the grade of the banks, these difficulties will be lessened but not entirely remedied. It is 23