WATERBURY, Vt. – Beginning next week, state officials and conservation groups in Vermont and New Hampshire will post signs along the White River and Connecticut River about an invasive algae that has been spotted in both, hoping to stem its spread.

The signs will appear at access points along the rivers, explaining how to properly disinfect gear and clothing of traces of Didymosphenia geminata, also known as didymo or rock snot, Agency of Natural Resources Secretary George Crombie announced Friday.

The state confirmed this week that the algae had been found in two locations – six miles apart – on the White River, in the towns of Royalton, Bethel and Stockbridge. Last week, didymo was spotted in the northern reaches of the Connecticut River.

The sign-posting initiative was announced after a meeting Friday of biologists from both states and representatives of Trout Unlimited and the White River Partnership. It was called in the wake of revelations that the algae had been spotted in rivers.

One way it is spread from river to river is on the clothing and equipment of fishermen, boaters or others who come into contact with even microscopic quantities.