2012-02-16_AgendaPacket - Laserfiche WebLink

Home

tLake Vegetation Management Plan The 15% limit is a level of plant control the DNR has confidence in that will allow riparian owners access to the lake while maintaining the basic functions and benefits that aquatic plants provide. Most lakes never reach the 15% limit for chemical control of aquatic plants. A variance is required to remove more than 15% of the littoral area and monitoring of the plant community and the water quality is required to ensure that cumulative impacts of aquatic plant removal are not resulting in harm to the lake. One of the situations the DNR considers issuing a variance to the 15% limit is for the selective control of invasive species to enhance ecological and recreational benefits. Currently, Eurasian Watermilfoil makes up a significant proportion of the plant community and could be an ecological and recreational nuisance on Lake Owasso. The overall diversity of native submersed plants, as measured by the mean number of native species per point (littoral zone), will be maintained or allowed to increase in the first year after bay -wide treatment. The mean number of native species per point may decrease during the year of bay -wide treatment. If the mean number of native species per point decreases during a year of bay -wide treatment, it is possible that bay -wide treatments may not be done during at least the first year following a bay -wide treatment in order to meet Goal 3. Bay -wide treatments may be repeated at intervals of every other to every third year, depending on trends in the frequencies of the target invasive plants and also non - target native plants. If the mean number of native species per point does not decrease during the first year of bay - wide treatment, then bay -wide treatments may be considered during the following year Monitoring data will be collected as described below. ❑ Variance approved without condition(s) ® Variance approved with following conditions(s): ® Pre - treatment data collection Narrative: Two pre - treatment point- intercept plant surveys and water quality data were collected by the Grass Lake WMO to serve as baseline data to compare the effectiveness of the treatment regime and to determine the impacts on the lake.. During each year of bay -wide treatment, the Lake Owasso Associations or its agent will inspect the lake prior to treatment to delineate areas to be treated. If any deviations from the most recent inventories are observed during pre - treatment inspections, these results should be noted and the treatments adjusted accordingly, in a manner consistent with the APM permit issued by the MnDNR. Treatment areas should be delineated using GPS and Geographic Digital Data, including all necessary electronic files, will be submitted to the DNR to enable re- creation with GIS software of all polygons, waypoints, track logs, etc. Lake Owasso LVMP 7