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Beaver Creek Soils

Soils Glossary


Principal Soil Series

Principal soil series found along the lower elevation streams, and in the pinyon-juniper and ponderosa pine types in the Beaver Creek watershed, are the Brolliar, Siesta, Sponseller, and Springerville series (Table 1).

Table 1. Soil series classified according to the current system of classification.

Order
Subgroup
Family
Series
Extent%
Mollisols Argic Cryoborolls Fine, montmorillonitic Brolliar 19.3
Alfisols Mollic Cryoboralfs Fine, montmorillonitic Siesta 4.8
Mollisols Argic Cryoborolls Fine-loamy, mixed Sponseller 2.8
Vertisols Typic Chromusterts Fine, montmorillonitic, mesic Springerville 25.7

 

Brolliar Series

The Brolliar series consists of moderately deep and deep, well-drained, noncalcareous soils on nearly level to hilly uplands. These soils formed in material weathered from porous basalt. They occur at elevations of 1,982 to 2,318 m (6,500 to 7,600 ft), where the annual precipitation is 500 to 580 mm (20 to 23 inches). These soils adjoin Siesta, Sponseller, and Friana soils. Plant cover consists chiefly of ponderosa pine, Gambel oak, Arizona fescue, mountain muhly, bluegrass, squirreltail, and junegrass.

Brolliar soils have a dark-brown surface layer that is soft when dry and has a platy structure. Their subsoil is reddish brown and is hard when dry. It has blocky structure. Basalt bedrock is at a depth of 0.6 to 1.5 m (2 to 5 ft). Stones and cobblestones cover 20 to 60 % of the surface of most areas. A layer of undecomposed and partly decomposed pine needles overlies the mineral soil.

Siesta Series

The Siesta series consists of moderately deep and deep, well-drained, noncalcareous soils on gently rolling and undulating uplands. These soils occur in the eastern part of the watershed, at elevations of 2,074 to 2,440 m (6,800 to 8,000 ft), where the average annual precipitation is 500 to 560 mm (20 to 22 inches). They adjoin Brolliar, Sponseller, Springerville, Friana, and Gem soils. Plant cover consists of a good stand of ponderosa pine, some Gambel oak, Arizona fescue, junegrass, mountain muhly, blue grama, iris, lupine, and annual weeds.

Siesta soils have a reddish-brown surface layer that is soft when dry and has platy and granular structure. Their subsoil is reddish-brown and very hard when dry. It has blocky structure. Their substratum is red, slightly hard when dry, and massive. Bedrock is at a depth of 66 to 150 cm (26 to 60 inches). In most places these soils contain small amounts of rounded gravel.

Sponseller Series

The Sponseller series consists of deep and moderately deep, well-drained, noncalcareous soils on gently sloping to steep side slopes of cinder cones. These soils formed in material weathered from volcanic cinders. They occur in the pine forest in the eastern part of the watershed, at elevations of 2,379 m (7,800 ft) or more, where the average annual precipitation is 560 to 600 mm (22 to 24 inches). They adjoin Brolliar and Siesta soils. The overstory consists of good stands of ponderosa pine, limber pine, Douglas-fir, aspen, Gambel oak, and New-Mexican locust. The ground cover is chiefly Arizona fescue, junegrass, mountain muhly, and blue grama.

Sponseller soils have a stony, dark reddish-brown surface layer that is hard when dry and has platy or granular structure. Their subsoil is reddish-brown, is hard when dry, and has blocky structure. Their substratum is gravelly and yellowish red, hard when dry, and massive. Volcanic cinders occur at a depth of 50 to 130 cm (20 to 52 inches). In most places a thick mat of needle litter overlies the mineral soil. There are a few stones and cobblestones and a little gravel. These soils are slightly acid or neutral.

Springerville Series

The Springerville series consists of moderately deep and deep, well-drained soils on the Coconino Plateau. The slope ranges from level to steep, and the topography from smooth and undulating to rough. These soils developed in material weathered from basalt and cinders. They occurs at elevations of 1,067 to 1.982 m (3,500 to 6,500 ft), where the average annual precipitation is about 280 to 460 mm (11 to 18 inches), and are associated principally with Gem, Brolliar, and Waldroup soils. In many places they are dissected by deep canyons.

At elevations of 1,220 to 1,982 m (4,000 to 6,500 ft), the vegetation consists chiefly of pinyon pine and juniper but includes a few Gambel oaks and, on the upper reaches of these soils, scattered ponderosa pine trees. The ground cover and the understory are chiefly blue grama and black grama but include some sideoats grama, squirreltail, turbinella oak, mountain-mahogany, snakeweed, and filaree. At elevations of 1,067 to 1,220 m (3,500 to 4,000 ft), the vegetation consists of mesquite, canotia, pricklypear, filaree and tobosa.

Springerville soils have a dark grayish-brown to reddish-brown surface layer that is slightly hard when dry and has platy or granular structure. The underlying layers are brown or reddish brown, are extremely hard when dry, and break into large, blocky aggregrates. The lower layers are calcareous in most places. In some places these soils are calcareous to the surface.

Horizons are difficult to distinguish because these soils have a strong tendency to shrink and swell, and much heaving and internal movement result. When the soils are dry, they have cracks 12 to 50 mm (half an inch to 2 inches) wide and 38 to 50 cm (15 to 20 inches) deep. The cracks disappear when the soils are wet.

 

The information provided above is taken from the following publication: Williams J.A. and T.C.Anderson, 1967 Soil Survey, Beaver Creek Area, Arizona, U.S. Department of Agriculture, Forest Service and Soil Conservation Service.

Soils Glossary

Calcareous: Soil containing sufficent free CaCO3 (calcium carbonate) and other carbonates to effervesce visibly when treated with cold 0.1M HCl (hydrochloric acid).

Coarse-loamy: A soil texture consisting of 25% or more very coarse and coarse sand and <50% of one other grade of sand.

Fine-loamy: A soil texture consisting of 30% or more fine sand and <30% very fine sand; or between 15 and 30% very coarse, coarse, and medium sand; or >40% fine and very fine sand, at least half of which is fine sand, and <15% very coarse, coarse, and medium sand.

Mesic: A soil regime that has mean annual soil temperatures of 8 degress Celsius or more, but <15 degrees C. Also, there is >5 degrees C difference between mean summer and mean winter soil temperatures at 50 cm below the surface.

Montmorillonitic: Soil that contains a significant amount of the clay mineral montmorillonite, a water-loving, highly expansive clay. It can cause soil to inhibit the flow of water through it.

Thermic: A soil regime that has mean annual soil temperatures of 15 degrees C or more, but <22 degrees C. Also, there is >5 degrees C difference between mean summer and mean winter soil temperatures at 50 cm below the surface.

Northern Arizona University         Merriam-Powell Center for Environmental Research         Rocky Mountain Research Station         MAB