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20 ~ sour suRVSY
<br />Nunn Series
<br />The Nunn series is made up of deep, well-drained soils.
<br />These soils formed on terraces and Galley side slopes in
<br />loamy alluvium. Slopes are 0 to 9 percent. Elevations are
<br />4;900 to 5.500 feet. 'flte native vegetation is mainlc short
<br />and mid grasses. annual precipitation is 12 to 18 inches.
<br />I\4ean annual air temperature is 48° to 52° F., and the
<br />frost-free season is about 140 to 155 days.
<br />In a representacice profile the surface layer is grayish-
<br />brown clay loam about 10 inches thick. The subsoil, about
<br />20 inches thick. is brown and very pale brown clay that
<br />grades to clay loam. It is nonca]careous in the upper part,
<br />but contains soft lime segregations in the lower part. The
<br />s»bstratllm is strongly calcareous, very pale brown clay
<br />loam estendin_ to a depth of 60 inches or more. In the
<br />surface lacer. soil reaction is neutral. In the upper part
<br />of the subsoil, it is mildlc alkaline, and in the lower part
<br />of the subsoil and in the substratum it is moderately
<br />alkaline.
<br />Nunn soils have slow and moderately slow permeabil-
<br />ity. Available water capacity for the profile is high. Roots
<br />can penetrnte to a depth of 60 inches or more.
<br />The acreage of these soils is used mainlc for irrigated
<br />and dryland crops and for pasture.
<br />Representative profile of Nunn clay loam. 0 to 1 percent
<br />slopes, located 1.^20 feet east and~1,000 feet north of
<br />center of sec. r, T. ? \r., R. 691V.:
<br />Ap-0 to 30 inches. grayish-brown-(lOTR 5/^_) clap loam, very
<br />dnrl: gracish brown (lOYR 3/^_) when moist; weak.
<br />medium. subangtilar blxkp strvcture that parts to
<br />weak. fine. granular; hard, firm; neutral; clear,
<br />smooth boundary.
<br />B21t-10 to 1S inches. brown (10YR 4/3) clap, dark brown
<br />(lOTR 3/3) when moist; moderate. medium. pris-
<br />matic structure that parts to strong, medium and
<br />fine, an_ntlar and subangular blocks; verc hard, very
<br />firm; thin. continuous clac films oa ped feces; mildlc
<br />alltaline: clear, wave boundary.
<br />B'Lotrn-1S to ?3 inches, brown (lOYR 5/3) clap, brown
<br />(lOTR 4/3) when moist; moderate. medium. pris-
<br />matic structure that parts to moderate, medium, attb-
<br />angulnr blxkp; very hard, very firm; thin. nearly
<br />crondnuons clay films on ped faces; stronglc calcare-
<br />ous, with few, fine and medium. prominent, white
<br />(lOTR S/2) lime segregations; moderately alkaline;
<br />clear, wasp boundary.
<br />B3tm-23 to 30 inches, very pale brown (lOTR i/3) clay
<br />loam, brown (lOYR 5/3) when moist; weal:. costae.
<br />prismatic structure that parts to moderate, medium.
<br />subnngular blxkp; Lard, ftrm; few, patchy clap
<br />films on ped faces; strongly etlctreous, with few,
<br />fine and medium. prominent, white (lOYR 8/^_) lime
<br />segregations; moderately alkaline; gradual, wavy
<br />boundary.
<br />Cm-30 to 80 inches, very pale brown (lOTR i/4) clay
<br />loam, yellowish brown (lOTR 5/4) when moist;
<br />massive; slightl3' hard, friable; strongly calcareous;
<br />moderately alkaline.
<br />The A horizon ranges from 6 in 14 inches in thickne~ and
<br />from sends clay loam to claT loam in texture. The B2t hori-
<br />zon ranges from 4 to 15 inches in thickness and from hence
<br />clay loom m elac in texture. Depth to calcium carbonate ac-
<br />cumulation ranges tram 14 to 30 inches. The C horizon ranges
<br />from heavy loam to clap loam in texture. Tppictlly the sand
<br />and gravel substratum is below a deptL of 60 inches, but in
<br />places It is between depths of 40 and 80 inrltes. As a result
<br />of excessive irrigation in some auras, a water ffible is prevent
<br />at a depth of between 3 and 5 feet
<br />Nunn sandy clay loam, 0 to 1 percent slopes (NnA).-
<br />This soil is throughout the eastern part of the Area. It
<br />occurs as irregularly shaped areas more than 3t' acres in
<br />size.
<br />The profile of this soil is much like the one c;escrzbed
<br />as representative fur the series, but rite surface layer is
<br />abotn 10 inches of sands clay loam. The subsoil :~ about
<br />6 inches of clay underlain by about °_° inches of calcar-
<br />eous clay loam.
<br />Included with this soil in mapping are small areas of
<br />Nunn clay loam. 0 to 1 percent slopes; Ascalon sandy
<br />loam. 0 to 1 percent slopes; and Fiim soils. These ii,clud-
<br />ed soils mal:e up about 10 percent of each mapped area.
<br />Runoff is slow on this soil. Permeability is moder;r.ely
<br />slow. Alt]touglt the erosion hazard is slight, this soil
<br />should be protected from soil blowing during periods of
<br />strong winds.
<br />Almost all of the acreage of this soil is used for irri-
<br />gated crops. A few area=_ are used for irrigated pnstnre.
<br />(Capability unit I, irrigated; tree :;uitability group 3)
<br />Nunn sandy clay loam, 1 to 3 p~°rcent slopes INn81.-
<br />This soil is in the eastern part of the Area. In most
<br />places it occurs as irregularly shaped areas more than 20
<br />acres in size.
<br />The profile of this soil is much ]il:e the one described as
<br />representative for the series, btrt the surface layer is
<br />about 10 inches of sandy clay loam. The subsoil is about
<br />4 inches of clay underlain by about 20 inches of calcar-
<br />eous clac loam.
<br />Included with this soil in mapping are some small areas
<br />of Iiim soils; Nunn clay loam, 1 to 3 percent slopes;
<br />Ascalon sandy loam. 1 to 3 percent slopes: and Iireld fine
<br />sandy loam, 1 to 3 percent slopes. These included soils
<br />make up about 15 percent of each mapped area.
<br />Runoff is medium on this soil. Permeability is moder-
<br />ately slow. The erosion hazard is moderate.
<br />Almost all of the acreage of this; soil is used for irri-
<br />gated crops. but a few small areas are used far irrigated
<br />pastures. (Capability unit. IIe-2, irrigated; tree suitabil-
<br />ity group 3)
<br />Nunn clay loam, 0 to 1 percent slopes INuAI.-This
<br />soil is in the eastern part of the Area. In most places it
<br />is in irregular areas more than 30 acres in size. This soil
<br />has the profile described as representative for the series.
<br />Included with this soil in mapping are small areas of
<br />Nunn sandy clay loam, 0 to 1 percent slopes; and Nunn
<br />clay loam, 1 to 3 percent slopes. Also included are a few
<br />small areas of Nunn clay loam, 0 to 1 percent slopes, that
<br />have a seasonal high water table. These included soils
<br />make up about 15 percent of each mapped area.
<br />Runoff is slow on this soil. Perrneabillty is slow. The
<br />erosion hazard is slight.
<br />Almost all of the acreage of flit:; soil is used for irri-
<br />gated crops, but a few small areas are used for irrigated
<br />pasture. (Capability unitIIs-1, irrigated; tree suitability
<br />group 3)
<br />Nunn clay loam, 1 to 3 percent slopes INuB).-This
<br />soil is in the raste.rn part of the Area. In most places
<br />it occurs as irregularh• shaped arels more than 40 acres
<br />in size.
<br />Included with this soil in mapping are small areas
<br />of Iiim soils; Nunn sandy clap loam. 1 to 3 percent
<br />slopes; Nnnn clay loam. 0 to 1 percent slopes: and Val-
<br />mont clay loam, 1 to 3 percent slopes. Also included
<br />near drainageways ate small wet :[teas and a few areas
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