Jun 24, 2011. /Lesprom Network/. Sierra Pacific Industries will open its newly renovated sawmill in Sonora, Calif., on June 27. The plant has been closed for approximately two years, as Random Lengths reported. Sierra Pacific Industries is a third-generation family-owned forest products company based in Anderson, California, USA. The firm owns and manages nearly 1.9 million acres of timberland in California and Washington, and is the second largest lumber producer in the United States.