Bladderwort and the Ecosystem

Bladderwort (Ultricularia) is the common name of more than 215 species of plants with about 20 percent of those species being rootless, free-floating aquatic plants that are sometimes noticeable by their small, yellow flower protruding from the surface of the water. The species is called Bladderwort because of its inherent bladder-like structures connected to the submerged segments of the plant. The plant is carnivorous and uses these bladders to capture tiny, aquatic organisms such as insect larvae and aquatic worms.

Under certain conditions, the plant may affect not only navigation and recreation, but the long-term sustainability of our drinking water and subsequent treatment efforts. Despite its reputation as an invasive plant, Bladderwort is not harmful to the lake, its wildlife or those who live on the lake. In fact, according to biologists, it is an indication of good water quality.

The plant itself is a normal and viable part of any other freshwater lake. Over the last several seasons, we have evaluated a number of methods to control the spread of Bladderwort, and recognize that this must be a team effort with lake lot owners and users.

In 2014, Spartanburg Water employed mechanical harvesters that cut and collect aquatic, invasive plants like Bladderwort, to support our requirement of offering an environmentally friendly method of controlling excessive aquatic plant growth and nuisance vegetation. We contracted the use of harvesters on the lake beginning in June and harvested into late July, focusing on priority locations that showed the highest density of Bladderwort. While the harvesters did provide temporary relief, the invasive plant repopulated approximately 50 percent of the area treated. Fortunately, these efforts helped to dramatically decrease the potential vegetative overgrowth impact to the lake later in the season and the following spring. 

In 2015, the next step in our Bladderwort reduction strategy included the application of safe, non-toxic aquatic herbicides applied by the South Carolina Department of Natural Resources (SCDNR). The first application of herbicides was applied on June 16. The area of treatment was focused upstream of the I-26 overpass and up to the headwaters. The second application of herbicides was applied July 20. There were no major interruptions to normal lake activities reported.

As we monitored the 2016 “growing” season for Bladderwort, populations of the species appeared to decline, requiring no additional efforts by SCDNR to repeat the large-scale herbicide applications that occurred in 2015. However, Spartanburg Water continues monitoring and invasive-species mapping initiatives and will make informed decisions if conditions warrant a change. Adjacent property owners do have the opportunity to do small-scale Bladderwort control around their dock or adjacent shoreline area with the appropriate permit.

If you would like information about applying for a permit to hire a private aquatic herbicide applicator, please call the Lake Bowen Warden’s Office at (864) 592-2240.

Click here to watch a short video about Bladderwort and the Ecosystem.