There are 2 federal agencies that manage "land", the US department of the Interior (the head of which is on the President's cabinet) Sally Jewell is the current head of the agency (and interestingly was born in the UK). They manage about 75% of all "public" land, and the BLM (Bureau of Land Management) is part of the US department of the Interior.
The other agency is the US Department of Agriculture(USDA), which is who owns the USFS(US forest Service) all the national parks, etc. The current boss of the USDA is Tom Vilsack and is also a member of the President's Cabinet.