Emergent Aquatic Vegetation

Emergent aquatic vegetation is an indicator of the littoral marsh condition in Lake Okeechobee. The Lake Okeechobee littoral marsh consists of approximately 100,000 acres bounded by the Herbert Hoover Dike and the 10 ft NGVD bathymetric contour. The distribution and composition of plant communities within this area is primarily a function of water depth, as well as the interaction between water depth and horizontal mixing of turbid, nutrient enriched water from the pelagic zone. Emergent aquatic vegetation provides important habitat for birds and other organisms.

See the results for emergent aquatic vegetation in Lake Okeechobee.

Photo credit: Andrew Rodusky.

How is it measured?

Emergent aquatic vegetation is measured by mapping of the littoral marsh every three years with frequency dependent on available funding. However, for the years when data are not available to map the entire marsh, assessment scoring is done annually based on evaluating the emergent plant communities within 50 one-hectare grids located at 24 representative sentinel sites distributed throughout the marsh. The thresholds are specific for different emergent plant communities and are based on the Interim Goals.

Threshold Levels

Vegetation TargetTarget (hectares)within 25% (hectares)within 50% (hectares)
Bulrush1,900 or greater1425-1,899950-1,424
Beakrush/Spikerush10,000 or greater7,500-9,9995,000-7,499
Sawgrass1,900 or greater1425-1,899950-1,424
Cattail8,000 or less8,001-10,00010,001-12,000
Willow3,000 – 5,0002,250-2,999 or 5,001- 6,2501,500-2,999 or 5,001-7,499
Floating leaf above 3.88m1,500 or less1,501-1,8751,501-2,250
Torpedograss2,000 or less2,001-2,5002,001-3,000
Other Invasive Exotics25 or less26-3233- 38
Woody Vegetation, Not Willow500 – 1,500  375-499 or 1,501-1,875250-499 or 1,501-2,250