State Soils

Just as many states have official state flowers, birds, and fossils, they also have official soils. State soils are most often determined by a vote of soil scientists in the state, and, absent any political wrangling, usually represent the most productive soils and those that most closely resemble everyone’s favorite soil: loam. As mentioned earlier, loam soils are almost equal parts sand, silt, and clay.


The Alaska state soil is a Gelisol called the Tanana series. These are important agricultural soils in Alaska, and when they are developed for agriculture, they can be used for hay, pasture, grains, and vegetables.


California’s state soil is the San Joaquin series, which covers more than 200,000 hectares (500,000 acres) of the Great Central Valley. Grapes, oranges, figs, and almonds are just a few of the crops grown on this Alfisol. This soil is also a favorite for urban development due to the presence of hardpan, roughly a meter (3.3 feet) below the surface, which restricts water percolation.


Given Hawai’i’s volcanic history, it should be no surprise that its state soil is an Andisol. The Hilo series covers more than 5,900 hectares (14,500 acres) and is a highly productive agricultural soil formed principally from weathered volcanic ash.


The Orovada series is the state soil of Nevada. An Aridisol, this soil is deep and well drained, having formed in loess that is high in volcanic ash. The presence of ash reduces the amount of water needed for irrigation, making this a valuable agricultural soil. It is primarily used to grow crops such as barley, winter wheat, alfalfa, and grass (for hay and pasture). Located mainly in the Great Basin portion of the Basin and Range, it covers more than 150,000 hectares (360,000 acres) of northern Nevada.


An Ultisol known as the Jory series is the state soil of Oregon. This series can be found on more than 120,000 hectares (300,000 acres) of land in the western part of the state. It is a very productive agricultural soil that is a favorite of the local wine industry. The name comes from Jory Hill in Marion County, which owes its name to a family that settled in the area in 1852.


The state soil of Washington is the Tokul series, an Andisol that formed in volcanic ash and loess over a dense glacial till containing high concentrations of manganese and iron. The name comes from a small community and creek located in King County. The state has more than 400,000 hectares (1,000,000 acres) of Tokul soils, the majority of which are located on the western side of the Cascade Range.