The community was so named on account of hay fields near Hayfork Creek. Service is also provided from Weaverville to Lewiston (MWF) and Hayfork (daily). Forest Glen is located on California State Route 36, south-southwest of Hayfork. Diversions off Hayfork Creek have only furthered the pollution problem by concentrating it. SR 3 is also known as Bramlot Road from its southern terminus to Hayfork. Trinity Center Airport, Weaverville Airport, Hayfork Airport, Hyampom Airport and Ruth Airport. The 2010 United States Census reported that Hayfork had a population of 2,368. The main tributaries are Hayfork Creek and the East Branch South Fork Trinity River. This stretch of road through the Shasta-Trinity National Forest parallels the Hayfork River. Hayfork is located at (40.571406, -123.146619). The Hayfork Valley is the largest agricultural area in Trinity County, with about of farmland. In the state legislature, Hayfork is in , and . Hayfork is a census-designated place (CDP) in Trinity County, California, United States.