Mn Wetland Conserv Act Tech. Eval.findings

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plant tissue that allow oxygen to be transported to the rhizomes,which is an essential adaptation In plants for survival in wetlands.Cutting the cattails and raising water levels above the cut stems and leaves drowns the cattails.This greatly reduces cattail density and prevents future germination.This technique was explored by the applicant.It would require flooding the basin and roadway embankment for an extended period of time. Hennepin County Transportation Department advises against raising water levels In the wetland.If cut leaves and stems are not submerged,however,this method becomes ineffective. Herbicide Another cattail management method is to apply herbicide.After herbicide application,the resultant exposed soil can be seeded with a native wetland seed mix.Where seeding wetland plants in exposed soil is a good technique for establishing native vegetation,it has not been shown that seeding alone will out-compete invading cattails.This may be because cattails have a competitive advantage when there is an abundance of cattail leaf litter.Therefore,if the cattail seedbed and litter has not been removed,it is likely that the area will remain dominated by cattails.Removing the cattail seedbed would require excavation. Proposed Thin-Spread Because manipulating the hydrology of the wetland Is not feasible and herbicide treatments alone will likely fail in the long-term,the applicant has proposed an innovative cattail management technique.This method involves the thin-spreading of excavated wetland soil over an area that is currently dominated by cattails. Existing cattail propagules will be removed from the excavated soil prior to spreading the material over an area of herbicide-killed and burned cattails.Thin-spreading this soil will bury the existing cattail seedbank and will reduce germination by eliminating light availability to cattail seeds.It will also create a large,level planting area to seed with a native wetland mix.When native wetland plants are allowed to establish without competition from invaders,they are good at outcompeting invasive species in the long term.Therefore,it is likely that this technique will result in long-term delivery of public benefits. V. Assurances To assure that the project is achieving intended restoration goals and improved public value,the applicant has outlined projected outcomes and proposed monitoring,maintenance and reporting.The applicant has collected two rounds of baseline wildlife data for birds,amphibians,and Odonata(dragonflies and damselflies).The applicant will be collecting another round of data this fall.Post-construction data will also be collected.These data have been compiled in order to document the response of birds,amphibians,and other biotic quality indicators to the restoration.This type of data collection will help to inform and educate wetland professionals on expectations for wildlife response following restoration. In addition to wildlife data,the applicant has committed to three years of post-construction wetland monitoring and reporting,and will follow the MN Board of Water and Soil Resources Replacement Wetland Annual Monitoring Report format.The applicant will perform short term management activities to meet performance standards and has set high performance standards for the restoration activities,which include less than 20%cover of invasive species and greater than 80%vegetation cover in the restored wet meadow community.The applicant will be required to submit the monitoring reports to the MCWD on or before January 11 of each year for 3 years. The applicant will be required by the Minnehaha Creek Watershed District to have financial assurance for the proposed wetland restoration.The District will have the option to draw upon this if warranted to do so.The financial assurance will be released to the applicant only when performance standards have been met at the end of the final year of monitoring. VI. Summary of Benefits The purpose of the Wetland Conservation Act is to achieve no net loss in Minnesota's wetlands and to increase the quantity,quality,and biological diversity of diminished wetlands by restoring or enhancing them. The proposed project will result in a more diverse,higher quality wetland that is composed of three wetland