Trees are in Sierra Pacific Industries' blood. The third-generation family-owned firm owns and manages nearly 1.9 million acres of timberland in California and Washington. With a network of sawmills, it's among the top lumber producers in the US. SPI's manufacturing plants also make mouldings and millwork, windows and doors, fencing, and wood fiber by-products, such as chips and shavings. Several of its sawmills also house co-generation facilities that recycle wood waste into power for its plants; excess electricity is sold to local public utilities. Additionally, SPI is involved in residential and commercial real estate. The company traces its roots to the 1920s when it was founded by R. H. "Curly" Emmerson.