Control Options

Negatives for Use in Inlet

Comments

Dredging

Cost, response time, logistics 

Removing soil that contains hydrilla tubers may be possible in some cases such as a small water bodies or a bay of a larger body.  Dredging expensive and it is difficult to find places to put the spoils, the soil that is removed, where any hydrilla tubers are guaranteed to not accidentally get back in a waterbody. 

Biocontrol

None exists at this time

Triploid Carp

Containment, cost, longevity

The main objection is containment.  Carp will eat all vegetation and can eventually remove all tubers.  The process takes longer than other methods, over 10 years would be likely for the Inlet.  Containment of the carp would not be possible.  The damage they would pose for the Lake is substantial. Read More...

Benthic matting

Effectiveness, costs, logistics

Benthic matting costs substantially more per acre than herbicide treatments.  It is difficult to maintain complete coverage of the mats during the entire season.  If plants are able to grow around the edge of the mat, they will simply thrive and spread on the top of the map.  Securing the mats posing a navigation hazard.  The mats have to be placed and removed each season, creating more disruption for Inlet users and logistical hurdles. Read More...

Diver Assisted Suction Harvesting(DASH)

Effectiveness, logistics, cost

DASH was tested on an area of the Inlet in 2011. (link) It was determined that DASH, as it is done now, is ineffective in tuber and plant removal and in fact creates a mechanism to spread the plant.  DASH costs more than herbicide treatments and takes longer to treat any given area which could lead to excessive hydrilla growth in some areas of the Inlet before they divers could get to the site. Read More...

Herbicides

Impacts on non-target organisms

Herbicides are the most cost effective method available for this system.  Herbicides will work in the shortest time frame.  They are also the most 'sure' method of treatment with respect to treating the whole area of the infestation.  There is extensive literature and actual experience for both herbicides being used, minimizing the likelihood of unexpected results. Read More...    

New Methods?

Data needed, Regulatory framework may not allow

The Task Force is open to any and all ideas about alternative methods to remove the hydrilla.  However, until a new method can be proven, the herbicide treatment will remain in place due to the threats posed by hydrilla and the speed with which the plant can re-establish itself treatment is stopped before all tubers are killed.