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NATIVEVE.DOC Page 1 <br /> Test Site Seeks Native Plants That Will Succeed on Channel Banks <br /> The importance of routine inspection and ongoing maintenance of flood control channels and levees was <br /> brought home recently by the emergency repairs to an eroded levee on the Willamette River above <br /> Springfield. The Amazon Channel banks are mowed twice annually to comply with the requirements of the <br /> Army Corps of Engineers and City Code, facilitate channel inspection and preserve designed carrying <br /> capacity. However, mowing machinery often cannot reach to the bottom of the channel. For much of its <br /> length 30 -50% of the bank falls below this "mowing line." Invasive exotic (nonnative) species such as <br /> blackberries, Scotch broom, and teasel, which are listed as nuisance vegetation in the City Code or noxious <br /> weeds by the Oregon Department of Agriculture, frequently dominate the channel banks in these zones, <br /> facilitating their spread. Staff of the Public Works Maintenance Division, assisted by a Looking Glass <br /> youth crew, have undertaken an effort to find native vegetation that can be established in these zones and <br /> compete successfully against the exotics with a minimum of human assistance. <br /> A typical section of channel between Polk and Chambers streets was selected as a test site. Its relatively <br /> short length, proximity to the maintenance yard, ease of access via major arterial streets and through <br /> adjacent park land made this section a logical choice. Looking Glass workers removed the exotic invasive <br /> vegetation and assisted the City's Wetlands Maintenance Specialist in planting aquatic vegetation at the <br /> water line. Most recently, low growing shrubs were placed in the upland zones formerly dominated by <br /> blackberries. Native plantings to date have been modest, but more will be completed as time and plant <br /> materials are available. The site will be closely monitored and the success of various plant varieties <br /> evaluated. The goal of the effort is to find successful combinations of native plantings that can be <br /> duplicated in other channel sections where site conditions preclude modification of channel banks. <br /> For more information please contact Tim Rhay or Bob Hammitt of Public Works Maintenance at 687 -5220. <br />