CHICAGO — A small Wisconsin agency that manages thousands of acres of state land has banned its 10 employees from working on climate change issues while on the job.

The measure was passed by a 2-to-1 vote on Tuesday during a board meeting of the Republican-controlled agency, the Board of Commissioners of Public Lands, which manages more than $1 billion in trust assets, including 77,000 acres of land, mostly in heavily forested northern Wisconsin.

One official who voted in favor of the ban, Brad D. Schimel, the state’s attorney general and a Republican, declined to answer questions about his vote. According to a recording of the meeting, a copy of which was provided to The New York Times, Mr. Schimel said that he did not consider the new rule a “gag” on employees because they could talk about climate change when they were away from the office.

The other supporter, Matt Adamczyk, the state treasurer, said in an interview that the new rule was designed to prevent employees from involving themselves in issues that go beyond what he sees as the agency’s mission.