SEIS - Eagle Lake Property Owner's Inc.

TABLE 3. MANAGEMENT OPTIONS FOR CONTROL OF ROOTED AQUATIC PLANTSOPTION MODE OF ACTION ADVANTAGES DISADV ANT AGES5.b) Flooding• Higher water level in the • Where water is available, this •Chemical controlsWater for raising the level mayspring can inhibit seed can be an inexpensive not be availablegermination and plant growth technique Potential peripheral flooding•Possible downstream impactsnormally associated with eliminated, merely retarded or•Many species may not beelevated water levels can delayed affected, and some may beflush seed and plant• Timing of water level control benefittedfragments from system can selectively favor certain•Algal nuisances may increasedesirable specieswhere nutrients are available• Higher flows which are • Plant growth need not be •Possihle toxicity to non-targetherbicides applied to target possible species of plants/animalsPossible downstream impacts;COI?tact or systemic poisons eliminate species may affect non-target areasMay achieve some algae within pondRestrictions of water use forvarying time after treatmentIncreased oxygen demand fromdecaying vegetationPossible recycl iog of nutrients toallow other growths6) Herbicides• Liquid or pelletized • Wide range of control is •area or to plants directly• May be able to selectively ••kill plants or limit growth•• Typically requires application control as well •every 1-5 yrs••Toxic to aquatic fauna as aCellular toxicant, suspected of some submersed plant function of concentration,membrane transport species formulation, and ambient waterdisruption•More often an algal control chemistryIneffective at colderliquid or granulartemperaturesformulations, often in•Copper ion persistent;conjunction with polymers oraccumulates in sediments orother herbicidesmoves downstream6.a) Forms of copper Contact herbicide • Moderately effective control ••• Applied as wide variety of agent •DSEIS for Eagle Lake 26 ENSR