ST. CLOUD  (AP) - A major search for an invasive aquatic weed that's new to Minnesota has found it in one more lake.

The Department of Natural Resources says a search of 178 lakes in 20 counties by 200 trained volunteers found starry stonewort in Grand Lake in Stearns County. DNR invasive species unit supervisor Heidi Wolf says they're pleased it's the only new infestation found this year, and it appears to be small.

Wolf says they're considering treatment options. Starry stonewort is very hard to kill. Herbicides often result in a "haircut" that kills the top of the plant but lets the rest regrow. Suction harvesting is another option. But the DNR is stressing prevention .

Starry stonewort has been found in nine Minnesota lakes, starting with Lake Koronis in Stearns County in 2015.