AQUATIC WEED CONTROL

Ponds  14,000 ponds east of highway 17

Ponds Two kinds of ponds  Ones that have weeds  Ones that will have weeds

AQUATIC WEEDS Algae  Photosynthesizing plant No roots, leaves, or flowers No roots, leaves, or flowers

AQUATIC WEEDS Algae  Microscopic algae: turns water green

AQUATIC WEEDS Algae  Filamentous: strands attach to rocks or float in mats

AQUATIC WEEDS Algae  Chara: resemble flowering plant Can be toxic to fish Can be toxic to fish

AQUATIC WEEDS Flowering Plants  Submersed Rooted plants that don't reach the surface Rooted plants that don't reach the surface

AQUATIC WEEDS Flowering Plants  Free-floating Floating plant that has dangling unattached roots Floating plant that has dangling unattached roots

AQUATIC WEEDS Flowering Plants  Free-floating Water Lettuce Water Lettuce

AQUATIC WEEDS Flowering Plants  Free-floating Water Hyacinth Water Hyacinth

AQUATIC WEEDS Flowering Plants  Free-floating  Water Hyacinth

AQUATIC WEEDS Flowering Plants  Free-floating Duckweed Duckweed

AQUATIC WEEDS Flowering Plants  Rooted-floating Crested Floating Heart Crested Floating Heart

AQUATIC WEEDS Flowering Plants  Emergent Rooted and emerging above water surface Rooted and emerging above water surface

AQUATIC WEED GROWTH LIGHT  Photic zone is the water with enough light to support growth  Bottom of photic zone is 1% of full sunlight  Silt water = 3"  Clear water as deep as 300'

AQUATIC WEED GROWTH NUTRIENTS Nitrogen and phosphorus  Phosphorus is the limiting nutrient Most important to free-floating plants Most important to free-floating plants  P pollution can cause algal blooms  Runoff is major contributor

AQUATIC WEED CONTROL Nutrient control  Buffer vegetation on shore Unmowed strip Unmowed strip

Shoreline  Turf will be undercut

AQUATIC WEED CONTROL

Nutrient control  Buffer vegetation on shore Wetland plants Wetland plants

Shoreline  Vegetate shoreline Wetland plants Wetland plants Wetland carpetWetland carpet

AQUATIC WEED CONTROL Nutrient control  Floating wetland Dangling roots support microbes (biofilm) Dangling roots support microbes (biofilm) Absorb nutrients Absorb nutrients

Shoreline Riprap shoreline  Stones control emergent weeds

AQUATIC WEED CONTROL Rip rap  Stabilize shoreline

AQUATIC WEED CONTROL Mechanical  Weed cutters that remove weeds  Slow 2 acres/day 2 acres/day

AQUATIC WEED CONTROL Drawdown  Solidify floating nutrients  Kill submersed weeds

AQUATIC WEED CONTROL Non-toxic blue dyes  Blocks light below 2'

AQUATIC WEED CONTROL Biological  Alligatorweed Flea Beetle Release controlled alligatorweed where flea beetle can overwinter Release controlled alligatorweed where flea beetle can overwinter  Water Hyacinth Mites, weevils and fungus released Mites, weevils and fungus released Limited success Limited success

AQUATIC WEED CONTROL Aeration  Fountains and turbines Aerobic conditions support microbes and fish Aerobic conditions support microbes and fish Reduce algae? Reduce algae?

AQUATIC WEED CONTROL Grass carp  Triploid (sterile)  Consume massive amounts of algae and weeds  Live 10 years

AQUATIC WEED CONTROL Tilapia  Feed on algae  Harvest to eat

AQUATIC WEED CONTROL Barley bales  Releases natural chemical  Green water only

AQUATIC WEED CONTROL UV Filter  Water passes by UV bulb  Controls algae only  Algal cells clump together or die

AQUATIC WEED CONTROL Chemicals  Some that are labeled for aquatic use  Consult label  Liquid, granule or pellet formulation Sinker adjuvant Sinker adjuvant

AQUATIC HERBICIDES Copper Sulfate (Cutrine)  Controls algae in drinking water supplies  Alkaline water (high carbonates) precipitate out copper Copper Chelates more stable in alkaline water Copper Chelates more stable in alkaline water

AQUATIC HEBRICIDES Emerged or floating weeds  Diquat (Reward) Less effective in muddy water Less effective in muddy water  2,4-D (Aquacide)  Glyphosate (Rodeo)

AQUATIC HEBRICIDES HERBICIDE APPLICATIONS  Start control early to avoid oxygen depletion Repeat other half after 2 weeks Repeat other half after 2 weeks

Fish Kill  MO decomposing plant material utilizes oxygen  Heavy weed or algae kill can deplete oxygen from water and kill fish  Control only 1/2 of area  High temperatures have less oxygen More susceptible to fish kill More susceptible to fish kill

AQUATIC HEBRICIDES  Volume needed for algae and free floating weeds Acre-feet = surface area (acres) X average depth  Average depth Half of maximum depth Half of maximum depthOR Average of several measurements Average of several measurements

Kiawah  115 ponds  343 acres  49 miles of shoreline

Kiawah   Bivalves (clams) filtering capacities Attaching to grid to floating wetlands, sinking them   Herbicide   Bioaugmentation   Tilapia and Grass Carp   Cost about $19/A annually

Aquatic Weed Database 