February’s Freeze Killed a Lot of Salvinia, Other Lake-Choking Weeds

According to the Louisiana Department of Wildlife and Fisheries, the February freeze was good for waterways throughout Louisiana.  The freeze didn’t eradicate giant salvinia or water hyacinth, but it did cut back giant salvina by about 95%.  The department says it’s harder to tell about water hyacinth, because their bulbs usually survive even if the plant looks dead.  The effects on giant salvinia varied around the state, department biologists said.

In north Louisiana, it doesn’t seem to be growing yet on waterbodies such as Turkey Creek Lake, Lake Darbonne and Caney Creek Reservoir. The department called that “a positive indicator that there has been an extensive kill of giant Salvinia.”

Unfortunately, it’s already showing signs of growing back in Caddo Lake, Lake Bistineau, Black Lake and Saline Lake, which had more extensive accumulations going into the winter. However, the department said much of that previous accumulation did die.

LDWF biologists will keep checking lakes statewide, and herbicide crews will spray lakes with chronic giant salvinia problems. The department also uses other methods to control water weeds, including drawdowns, biological controls such as salvinia weevils, and private contractor spraying.

Source: “Louisiana: February Freeze Killed Lots of Giant Salvinia,” ktbs.com, accessed March 31, 2021, https://www.ktbs.com/news/louisiana-february-freeze-killed-lots-of-giant-salvinia/article_4839045c-90b4-11eb-89f5-c7b90e535f02.html.