Employees were told at about 3:30 p.m. Thursday, the Brainerd Dispatch reports. Production expected to cease in April, the Dispatch says.
The Wisconsin-based company announced last month that it would sell the Brainerd mill, along with Wisconsin mills in Mosinee and Rhinelander.
The three mills manufacture paper used for packaging, linings and masking tape.
Economic pressures have been forcing the closure of paper mills across the Midwest, the Milwaukee Journal Sentinel notes.
Wausau is under hostile pressure from a Manhattan hedge fund called Starboard Value LLC, which is arguing that paper for printing and publishing has become a money-losing business in the age of the e-book, Wi-Fi and the iPad. Starboard became the biggest shareholder of Wausau in 2011 and has since doubled its stake to 14.8 percent, the newspaper reported.
Starboard wants Wausau to focus solely on making towels used in public restrooms, the Journal Sentinel said.