How can Anderson Ranches have grass available year-round?

Anderson Ranches is located in Brownsville, the east side of the Willamette Valley in Oregon. The valley climate is very mild with lots of rain, 45-60 inches a year. The grass is always green. The valley has little freezing in the winter and fairly cool summers. The Willamette Valley is known for growing grass seed. In fact, The Willamette Valley is the grass seed capitol of the world.