Compatibility of North Dakota Soils for Irrigation

Abbreviations for soil texture, from coarse to fine, used in this publication:

In the following text,
      < = less than
      > = greater than
dS/m = deciSiemens per meter
EC = electrical conductivity
SAR = sodium absorption ratio

Irrigable Soils (i)

Irrigable soils generally require less management than conditional soils. Even though the soils are in an irrigable class, good irrigation management is essential. Attention to the allowable irrigation water quality is important. The use of lower-quality water than recommended can lower the productivity of the soils from salts and sodium. Different phases of each soil series may modify irrigation recommendations.

1i. Brandenburg, Coe, Kirby, Ringling, Sioux, Tinsley, Wabek, Wamduska, Wibaux

Drainage: excessively drained
Surface texture: L, SL
Substratum texture: sand and gravel
Surface intake rate for sprinkler irrigation: 0.5-0.7 inch/hour for slopes < 6 percent
Limiting permeability within 40 inches: 0.6 to 2 inches/hour in the upper part and > 6 inches/hour in the lower part
Profile characteristics: shallow/very shallow (< 20 inches) to sand, gravel and porcellanite (scoria)
Depth to lime: 0-10 inches
Surface pH: 6.6-8.4
EC (maximum within 40 inches in dS/m): 0
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality

Maximum allowable EC < 3 dS/M; maximum allowable SAR <12

Water Management Practices
Water management on these soils is critical because of low available water capacity and nutrient leaching hazard.

2i. Aylmer, Banks, Blanchard, Claire, Falsen, Flaming, Lohnes, Sandberg, Serden, Seroco, Valentine, Yetull, Zeona

Drainage: moderately well to excessively drained
Surface texture: CoS, S, FS, LCoS, LS, LFS, CoSL, SL, FSL
Subsoil texture: FS, S, LCoS, CoS
Surface intake rate for sprinkler irrigation: 0.5->1 inch/hour for slopes < 9 percent
Limiting permeability within 40 inches: 6-20 inches/hour
Profile characteristics: sandy and moderately coarse-textured material
Depth to lime: 10-30 inches
Surface pH: 6.1-7.3
EC (maximum within 40 inches in dS/m): 0
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m; maximum allowable SAR <12

Water Management Practices
Water management on these soils is critical because of low available water-holding capacity and nutrient leaching hazard.

3i. Appam, Arvilla, Binford, Clontarf, Cozberg, Hanly, Hecla, Hilaire, Lihen, Maddock, Manning, Metigoshe, Osakis, Ruso, Schaller, Sverdrup, Telfer, Walum

Drainage: moderately well to somewhat excessively drained
Surface texture: FSL, SL, CoSL, LFS, LS
Subsoil and substratum texture: SL and L in the upper part and LS to sand and gravel in the lower part
Surface intake rate for sprinkler irrigation: 0.4-1.5 inches/hour for slopes < 6 percent
Limiting permeability within 40 inches: 2-20 inches/hour in the upper part and > 6 inches/hour in the lower part
Profile characteristics: moderately coarse and medium-textured material in the upper part and coarse-textured material in the lower part
Depth to lime: 10-30 inches
Surface pH: 6.1-7.8
EC (maximum within 40 inches in dS/m): 0
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m; maximum allowable SAR <12

Water Management Practices
An irrigation scheduling system must be used.

4i. Breien, Chinook, Egland, Embden, Glendive, Inkster, Mott, Parshall, Tally, Trembles, Velva

Drainage: well and moderately well drained
Surface texture: SL, FSL, L
Subsoil texture: SL, FSL, L
Surface intake rate for sprinkler irrigation: .5-1 inch/hour for slopes < 6 percent
Limiting permeability within 40 inches: 0.6-6 inches/hour
Profile characteristics: moderately coarse and medium-textured material
Depth to lime: 10-20 inches
Surface pH: 6.1-8.4
EC (maximum within 40 inches in dS/m): 0-2
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m; maximum allowable SAR <12

Water Management Practices
An irrigation scheduling system must be used.

5i. Baahish, Brantford, Hidatsa, Kensal, Lehr, Renshaw, Shibah, Wanagan, Warsing

Drainage: well and moderately well drained
Surface texture: SL, L
Substratum texture: 2C material is GrSL to sand and gravel
Surface intake rate for sprinkler irrigation: 0.5-0.7 inch/hour for slopes < 6 percent
Permeability within 40 inches: 0.6-2 inches/hour in the upper part and > 6 inches/hour in the lower part
Profile characteristics: moderately coarse and medium-textured material over sand and gravel that is shallow to moderately deep (< 40 inches)
Depth to lime: 10-20 inches
Surface pH: 6.1-7.8
EC (maximum within 40 inches in dS/m): 0 to 1
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m; maximum allowable SAR <9

Water Management Practices
An irrigation scheduling system must be used.

6i. Bowdle, Brisbane, Bulltop, Chanta, Fordville, Littlemo, Ridgelawn, Spottswood, Stady, Vang

Drainage: moderately well and well drained
Surface texture: L, SIL, CL
Subsoil texture: L and CL in B horizons and GrL to GrS in the 2B or 2C horizons
Surface intake rate for sprinkler irrigation: 0.5-0.7 inch/hour for slopes < 6 percent
Limiting permeability within 40 inches: 0.6-2 inches/hour in the upper part and > 6 inches/hour in the lower part
Profile characteristics: moderately fine-textured material over moderately deep (20-40 inches) sand and gravel
Depth to lime: 15-30 inches
Surface pH: 6.1-7.3
EC (maximum within 40 inches in dS/m): 0-1
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m: maximum allowable SAR < 9

Water Management Practices
An irrigation scheduling system must be used.

7i. Arnegard, Beotia, Eckman, Emrick, Gardena, Heimdal, Kremlin, Linton, Mandan, Roseglen, Shambo, Straw, Tansem

Drainage: moderately well and well drained
Surface textures: VFSL, SIL, L
Subsoil texture: VFSL, SIL, L, SICL
Surface intake rate for sprinkler irrigation: 0.1-0.5 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.2-2 inches/hour
Profile characteristics: medium and moderately fine-textured material
Depth to lime: 15-30 inches
Surface pH: 6.6-7.8
EC (maximum within 40 inches in dS/m): 0-2
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 2.25 dS/m; maximum allowable SAR < 6

Water Management Practices
An irrigation scheduling system must be used.

Conditional soils can be irrigated under a high level of management. Soil conditions that contribute to conditional status are the presence of salts, poor drainage properties, the presence of subsurface layering, and the need for supplemental surface and subsurface drainage. Irrigation without high levels of management may degrade the soil quality for future generations but can be irrigated successfully if recommendations are followed. Soil phases of each soil series may modify irrigation recommendations.

8c. Aastad, Barnes, Bowbells, Bryant, Falkirk, Farland, Farnuf, Felor, Forman, Golva, Grassna, Great Bend, Hamlet, Korell, Kranzburg, La Prairie, LaDelle, Lakoa, Lankin, Lismore, Makoti, Max, Overly, Svea, Temvik, Walsh, Williams, Wilton

Drainage: moderately well to well drained
Surface texture: L, SIL, SICL
Subsoil texture: L, CL, SICL
Surface intake rate for sprinkler irrigation: 0.1-0.7 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.2-2 inches/hour
Profile characteristics: medium and moderately fine-textured material
Depth to lime: 10-20 inches
Surface pH: 6.1-7.8
EC (maximum within 40 inches in dS/m): 0-4
SAR (maximum within 40 inches): < 2

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.5 dS/m; maximum allowable SAR < 6

Water Management Practices
These soils are conditional for irrigation due to moderate and moderately slow permeability and a potential for salinity increase in the subsoil. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. Water, additional to that used for crop production, may be required for leaching. Leaching should be done in the fall or early spring, when crop requirements for water are low. An irrigation scheduling system must be used.

9c. Balaton, Buse, Cherry, Esmond, Fairdale, Havre, Havrelon, Korchea, Lambert, Langhei, Lonna, Machetah, Patent, Rondell, Rusklyn, Sakakawea, Sisseton, Sutley, Vida, Zahl, Zell

Drainage: moderately well and well drained
Surface texture: VFSL, FSL, SL, L, SIL, CL, SICL 2/
Subsoil texture: L, SIL, CL, SICL
Surface intake rate for sprinkler irrigation: 0.5-0.7 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.6-2 inches/hour
Profile characteristics: calcareous/medium and moderately fine-textured materials
Depth to lime: 0-10 inches
Surface pH: 6.6-8.4
EC (maximum within 40 inches in dS/m): < 4
SAR (maximum within 40 inches): < 2

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.8 dS/m; maximum allowable SAR < 6

Water Management Practices
These soils are conditional for irrigation due to moderate and moderately slow permeability and a potential for salinity increase in the subsoil. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. Water, additional to that used for crop production, may be required for leaching. Leaching should be done in the fall or early spring, when crop requirements for water are low. An irrigation scheduling system must be used.

10c. Bearpaw, Bottineau, Croke, Ethridge, Grail, Kelvin, Mondamin, Savage, Tanna, Waukon, Zeeland

Drainage: moderately well and well drained
Surface texture: L, CL, SICL
Subsoil texture: CL, SICL, SIC, C (> 35 percent clay)
Surface intake rate for sprinkler irrigation: 0.1-0.5 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.06-0.6 inch/hour
Profile characteristics: moderately fine to fine-textured material
Depth to lime: 15-40 inches
Surface pH: 6.1-7.8
EC (maximum within 40 inches in dS/m): < 4
SAR (maximum within 40 inches): < 4

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1 dS/m; maximum allowable SAR < 6

Water Management Practices
These soils are conditional for irrigation due to moderately slow and slow permeability and a potential for salinity increase in the subsoil. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. Water, additional to that used for crop production, may be required for leaching. Leaching should be done in the fall or early spring, when crop requirements for water are low. Subsurface drainage may be required for continued irrigation. An irrigation scheduling system must be used.

11c. Aberdeen, Alkabo, Belfield, Cathay, Cresbard, Niobell

Drainage: moderately well and well drained
Surface texture: L, SIL, SICL
Subsoil texture: CL, SICL (> 35 percent clay)
Surface intake rate for sprinkler irrigation: 0.1-0.7 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.06-0.2 inch/hour
Profile characteristics: moderately fine and fine-textured material that have a degraded natric horizon within 20 inches
Depth to lime: 20-30 inches
Surface pH: 5.6-7.3
EC (maximum within 40 inches in dS/m): 2-8
SAR (maximum within 40 inches): 5-15

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.5 dS/m; maximum allowable SAR < 4

Water Management Practices
These soils are marginal for irrigation, and irrigation of extensive areas should be avoided. Continued irrigation potentially could cause restricted water intake and permanent soil damage. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. Water, additional to that used for crop production, may be required for leaching. Leaching should be done in the fall or early spring, when crop requirements for water are low. Subsurface drainage may be required for continued irrigation.

12c. Amor, Boxwell,Chama, Edgeley, Little Horn, Marmarth, Moreau, Morton, Omio, Reeder, Regent, Searing, Sen, Watrous

Drainage: well drained
Surface texture: L, SIL, SICL
Subsoil texture: L, SIL, SICL
Surface intake rate for sprinkler irrigation: 0.1-0.5 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.0-0.6 inch/hour depending on texture of soft weathered bedrock
Profile characteristics: medium and moderately fine-textured materials moderately deep (20-40 inches) to soft weathered bedrock
Depth to lime: 10-20 inches
Surface pH: 6.1-7.8
EC (maximum within 40 inches in dS/m): 2-8
SAR (maximum within 40 inches): 0-4

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.8 dS/m; maximum allowable SAR < 6

Water Management Practices
These soils are marginal for irrigation due to moderately deep (20-40 inches) bedrock and the potential for lateral seepage. Avoid irrigating extensive areas or where stratification is evident and seeps are present. Salinity monitoring should be done on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

13c. Beisigl, Lefor, Rhame, Tusler, Vebar

Drainage: well to somewhat excessively drained
Surface texture: LS, LFS, SL, FSL
Subsoil texture: LS, LFS, SL, FSL
Surface intake rate for sprinkler irrigation: 0.5-1.5 inches/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.0-0.6 inch/hour
Profile characteristics: coarse and moderately coarse-textured material moderately deep (20-40 inches) to soft weather beds
Depth to lime: 10-20 inchesSurface pH: 6.1-7.8
EC (maximum within 4 inches in dS/m): 0
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.8 dS/m; maximum allowable SAR < 6

Water Management Practices
These soils are marginal for irrigation due to moderately deep (20-40 inches) bedrock and the potential for lateral seepage. Avoid irrigating extensive areas or where stratification is evident and seeps are present. Salinity monitoring should be done on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

14c. Dickey, Flaxton, Krem, Lanona, Livona, Swenoda, Towner, Virgelle, Yegen

Drainage: moderately well and well drained
Surface texture: LS, LFS, SL, FSL
Subsoil texture: L, CL, SICL
Surface intake rate for sprinkler irrigation: 0.5-1.5 inches/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.2-0.6 inch/hour
Profile characteristics: coarse-textured material over medium and moderately fine-textured material
Depth to lime: > 15 inches
Surface pH: 6.1-7.3
EC (maximum within 40 inches in dS/m): 0-4
SAR (maximum within 40 inches): < 2

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.8 dS/m; maximum allowable SAR < 9

Water Management Practices
These soils are conditional for irrigation due to the subsoil’s moderately slow permeability and potential for increased salinity. Salinity in the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. Water, additional to that used for crop production, may be required for leaching. Leaching should be done in the fall or early spring, when crop requirements for water are low. An irrigation scheduling system must be used.

15c. Antler, Augsberg, Bearden, Bigsandy, Cashel, Colvin, Doran, Flom, Galchutt, Gilby, Hamerly, LaMoure, Lowe, McKeen, Neche, Perella, Rauville, Regan, Roliss, Styrene, Vallers, Wheatville, Winger, Wyard

Drainage: somewhat poorly and poorly drained
Surface texture: L, SIL, SICL, SIC, C
Subsoil texture: L, SIL, SICL, SIC, C
Surface intake rate for sprinkler irrigation: 0.1-0.7 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.2-0.6 inch/hour
Profile characteristics: medium to fine-textured materials
Depth to lime: 0-10 inches
Surface pH: 6.6-8.4
EC (maximum within 40 inches in dS/m): < 6
SAR (maximum within 40 inches): < 3

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.5 dS/m; maximum allowable SAR < 6

Water Management Practices
Irrigate only if adequate surface and subsurface drainage has been provided. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

16c. Divide, Marysland

Drainage: somewhat poorly and poorly drained
Surface texture: L, CL, SIL
Subsoil texture: L, CL
Surface intake rate for sprinkler irrigation: 0.1-0.5 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.6-2 inches/hour in the upper part and > 6 inches/hour in the lower part
Profile characteristics: Aeric and Typic Calciaquolls, medium and moderately fine-textured material over sand and gravel
Depth to lime: 0-10 inches
Surface pH: 7.4-8.4
EC (maximum within 40 inches in dS/m): < 2
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m; maximum allowable SAR < 9

Water Management Practices
Irrigate only if adequate surface and subsurface drainage has been provided. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

17c. Bohnsack, Borup, Elmville, Fram, Glyndon

Drainage: somewhat poorly and poorly drained
Surface texture: FSL, SIL, L
Subsoil texture: FSL, SIL, L
Surface intake rate for sprinkler irrigation: 0.5-1 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.6-2 inches/hour
Profile characteristics: Aeric and Typic Calciaquolls, moderately coarse and medium-textured material
Depth to lime: 0-10 inches
Surface pH: 7.4-8.4
EC (maximum within 40 inches in dS/m): < 6
SAR (maximum within 40 inches): 0-1

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 2.25 dS/m; maximum allowable SAR < 6

Water Management Practices
Irrigate only if adequate surface and subsurface drainage has been provided. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

18c. Banks (variant), Bantry, Cormant, Fossum, Garborg, Hamar, Karlsruhe, Minnewaukan, Poppleton, Rosewood, Ulen, Venlo, Verendrye, Wyrene

Drainage: somewhat poorly and poorly drained
Surface texture: CoSL, LFS, LS, FS, S
Subsoil texture: LFS, LS, S, FS
Surface intake rate for sprinkler irrigation: 0.5-1.5 inches/hour for slopes < 3 percent
Limiting permeability within 40 inches: 2-20 inches/hour
Profile characteristics: coarse and moderately coarse-textured material
Depth to lime: 0-30 inches
Surface pH: 6.1-8.4
EC (maximum within 40 inches in dS/m): 0-2
SAR (maximum within 40 inches): 0-1

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m; maximum allowable SAR < 12

Water Management Practices
Irrigate only if adequate surface and subsurface drainage has been provided. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

19c. Arveson, Delamere, Fossum, Galatin, Mantador, Tiffany, Tolna, Wyndmere, Wyrene

Drainage: somewhat poorly and poorly drained
Surface texture: VFSL, FSL, SL
Subsoil texture: VFSL, FSL, SL
Surface intake rate for sprinkler irrigation: 0.5-1.25 inches/hour for slopes < 3 percent
Limiting permeability within 40 inches: 2-6 inches/hour
Profile characteristics: moderately coarse and medium-textured material
Depth to lime: Calciaquolls 0-10 inches, Aquolls > 20 inches
Surface pH: 6.1-8.4
EC (maximum within 40 inches in dS/m): 0-2
SAR (maximum within 40 inches): 0-1

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 3 dS/m; maximum allowable SAR < 12

Water Management Practices
Irrigate only if adequate surface and subsurface drainage has been provided. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

20c. Espelie, Grimstad, Kratka, Rockwell, Tiffany, Wyndmere

Drainage: somewhat poorly and poorly drained
Surface texture: L, FSL, SL, LFS, LS
Subsoil texture: SL, SIL, L, CL
Surface intake rate for sprinkler irrigation: 0.5-1.5 inches/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.2-2 inches/hour
Profile characteristics: coarse and moderately coarse-textured material over medium-textured material
Depth to lime: 0 -10 Inches
Surface pH: 7.4-8.4
EC (maximum within 40 inches in dS/m): < 4
SAR (maximum within 40 inches): < 2

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1.8 dS/; maximum allowable SAR < 9

Water Management Practices
Irrigate only if adequate surface and subsurface drainage has been provided. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. An irrigation scheduling system must be used.

21c. Gwinner, Hattie, Hoffmanville, Lawther, Lohler, Magnus, Marias, Nutley, Olga, Peever, Promise, Rolette, Rolla, Scorio, Sinai, Wahpeton, Wildrose, Wolf Point

Drainage: moderately well and well drained
Surface texture: SIC, C
Subsoil texture: SIC, C
Surface intake rate for sprinkler irrigation: 0.1-0.2 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.06-0.2 inch/hour
Profile characteristics: fine-textured material
Depth to lime: 0-20 inches
Surface pH: 7.3-8.4
EC (maximum within 40 inches in dS/m): 1-4
SAR (maximum within 40 inches): 0-1

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1 dS/m; maximum allowable SAR < 6

Water Management Practices
These soils are conditional for irrigation due to moderately slow and slow permeability and a potential for salinity increase in the subsoil. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. Water, additional to that used for crop production, may be required for leaching. Leaching should be done in the fall or early spring, when crop requirements for water are low. Subsurface drainage may be required for continued irrigation. An irrigation scheduling system must be used.

22c. Dimmick, Dovray, Enloe, Fargo, Fulda, Grano, Hegne, Lallie, Lindaas, Ludden, McDonaldsville, McKenzie, Parnell, Southam, Suomi, Thiefriver, Tonka, Viking

Drainage: poorly drained and drained phases of poorly and very poorly drained
Surface texture: L, SIL, SICL, SIC, C
Subsoil texture: SIC, C
Surface intake rate for sprinkler irrigation: 0.1-0.4 inch/hour for slopes < 3 percent
Limiting permeability within 40 inches: 0.06-0.2 inch/hour
Profile characteristics: medium to fine-textured material in the upper part and fine-textured material in lower part
Depth to lime: 0 > 40 inches
Surface pH: 6.1-8.4
EC (maximum within 40 inches in dS/m): < 4
SAR (maximum within 40 inches): 0

Water-holding Capacity (rounded to the nearest 0.5 inch; on-site values may vary)

Irrigation Water Quality
Maximum allowable EC < 1 dS/m; maximum allowable SAR < 6

Water Management Practices
These soils are conditional for irrigation due to slow permeability, wetness and a potential for salinity increase. Salinity of the root zone should be monitored on a three- to five-year basis or more frequently if plant growth is restricted. Water, additional to that used for crop production, may be required for leaching. Leaching should be done in the fall or early spring, when crop requirements for water are low. An irrigation scheduling system must be used.

These are soils with very severe limitations to irrigation because of one or more of the following: slope, sodicity, salinity, excessively slow permeability, root restrictive subsoil layering. Irrigation is strongly discouraged. Irrigation will cause soil quality to be degraded and reduce the productivity of the soils for future generations of farm producers. Different phases of each soil series will modify irrigation recommendations.

23n. Nonirrigable because of relief (slopes > 6 percent), depth or root restrictive substrata

Arikara, Buse, Cabba, Cohagen, Dumps, Dune Land, Flasher, Sioux, Werner

24n. Nonirrigable because of relief (slopes > 6 percent), sodicity (SAR > 13 within 40 inches), salinity (EC > 4 dS/m), slow or very slow permeability, or root restrictive subsoil

Absher, Barkof, Beckton, Cavour, Daglum, Desart, Dogtooth, Ekalaka, Evridge, Exline, Ferney, Gerda, Harriet, Heil, Hoven, Janesburg, Ladner, Lakota, Larson, Lemert, Letcher, Maltese, Manfred, Mekinock, Miranda, Nahon, Noonan, Oburn, Portal, Ranslo, Rhoades, Ryan, Scairt, Stirum, Totten, Uranda, Whitebird

25n. Nonirrigable because of salinity (EC > 8 dS/m) and slopes < 6 percent

Antler, Arnegard, Arveson, Bearden, Belfield, Benz, Borup, Colvin, Divide, Easby, Elmville, Ojata, Fargo, Fossum, Fram, Gilby, Glyndon, Grano, Grassna, Hamerly, Hegne, Ladelle, Lallie, LaMoure, Lohler, Ludden, Mandador, Moreau, Ojata, Overly, Parshall, Patent, Playmoor, Regan, Savage, Scorio, Sham, Vallers, Vanda, Velva, Wyndmere.

These soils may be classified in other groups without salinity.

26n. Nonirrigable due to shallow depth of root restrictive substrata (slopes < 6 percent)

Bainville, Cabba, Cabbart, Cedarpan, Dilts, Duncom, Dupree, Farfeld, Fleak, Kloten, Lisam, Midway, Wayden, Yawdim

27n. Nonirrigable because of seasonal or semipermanant ponding. Slopes < 1 percent

Very poorly drained Arveson, Borup, Colvin, Dimmick, Fargo, Fossum, Hegne, Lallie, Ludden, Marysland, McKeen, Neche, Parnell, Rauville, Regan, Roliss, Rosewood, Southam, Venlo.

Peat and Muck soils: Eramosh, Markey, Rifle, Seelyeville.

These soils may be classified in other groups but are poorly drained.

28n. Nonirrigable because of frequent flooding (> 50 percent chance of flooding)

Banks, Breien, Cashel, Colvin, Divide, Fairdale, Glendive, Hanly, Havre, Havrelon, Korchea, Korell, La Prairie, LaDelle, Lallie, LaMoure, Lohler, Ludden, Magnus, Marysland, Minnewaukan, Neche, Ojata, Patent, Playmoor, Rauville, Regan, Rhoades, Scorio, Straw, Svea and Trembles, Velva, Wolfpoint.

These soils may be classified in other groups with a lower chance of flooding.

29n. NonIrrigable due to numerous surface stones or boulders

Amor, Barnes, Beisigl, Boxwell, Buse, Cabba, Cabbart, Forman, Marmarth, Max, Morton, Reeder, Ringling, Sioux, Svea, Vallers, Vebar, Wabek, Wamduska, Williams, Zahl.

These soils may be classified in other groups because they have less surface stones.

Soil depth depends on the potential rooting depth of the plants to be grown and any restrictions within the soil that may hinder root growth. The rooting depth of potatoes may be only 18 to 24 inches, while alfalfa has a rooting depth of more than 4 feet. Discontinuities in the soil from layers of sand, gravel or bedrock may serve to physically limit the depth of root penetration.

The percentage of sand, silt and clay-sized particles determines the texture. Texture influences other properties, such as water-holding capacity, infiltration rate and internal drainage.

Movement of water into and within soils is partially dependent on soil structure. Soil structure refers to how sand, silt and clay particles are arranged in the soil. Particles aggregate via organic matter and associated biological activity, roots, soil mineral composition, freeze-thaw cycles, wet-dry cycles and time. Outside forces can impact aggregation and soil structure, such as compaction. Soils containing aggregates are unstable under irrigation and may require special management.

Water-holding capacity is defined as the soil water retained between a suction of 0.1 to 0.5 bars (field capacity) and 15 bars (permanent wilting point). Water held between these two suction values is regarded as plant-available water. A silt loam soil holds about 2.25 to 2.5 inches of water per foot of soil. A sandy loam can hold only about 1 inch of water per foot. Soil with high organic matter can hold more water than a soil with similar texture and lower organic matter.

Slope is important in determining the runoff potential of water from a field. Water and soil losses from runoff reduce short-term and long-term economic returns. Generally, more runoff will occur on fine-textured soils, compared with coarser-textured soils on similar slopes.

The infiltration rate is the relative rate that water penetrates and moves into the soil after a rain or irrigation event. The rate of infiltration is dependent on soil texture and structure but primarily is controlled by the surface conditions such as slope, roughness, residue and soil moisture. At the beginning of a rain or irrigation event, a dry soil surface will absorb more water than a wet surface, thus affecting the amount of potential runoff. A faster infiltration rate allows less runoff than soil with slower rates.

Internal drainage describes the degree and persistence of soil wetness and is influenced by slope, soil infiltration rate, soil texture (percent gravel, sand, silt and clay) and depth to the water table or impermeable layers. Excessively drained soils often have crop production problems related to lack of water and nutrients due to rapid movement of water through the soil profile. On the other hand, soils with poor internal drainage that remain wet may increase disease potential to crops, or cause denitrification losses of nitrogen fertilizer or the accumulation of salts. Soils with good internal drainage respond well to irrigation. Soil retains irrigation water for crops to use while allowing sufficient movement of water within the soil to minimize saturation of pore space.

High levels of soluble salts at or near the surface usually are the result of a high water table but also can accumulate through the years from dissolved salts in the irrigation water. High salt levels may reduce crop yields and increase the water requirement of plants. Irrigation may decrease the depth to the water table through time in some soils, thus increasing the risk of salinization. As salinity increases, crop productivity will decrease. Salinity is a soil property that changes relatively quickly with time, compared with other properties such as texture. Soil testing for salts is necessary to not only follow possible increases through time in irrigated fields but also determine if irrigation should be attempted in the first place.

Salts are detected by measuring the flow of electrical current through a sample of soil or water. The more salts in a sample, the less resistance to electrical current and greater the electrical conductivity (EC). There are several methods to measure EC. The 1:1 method (one-part deionized water to one part soil) has become popular because it provides very fast results. However, all EC ratings in this publication were derived from the saturated paste laboratory method.

Sodium (Na) affects the physical condition of the soil by dispersing soil aggregates. The soil becomes pasty when wet and develops a condition called “puddling,” where water remains on the surface for an extended period. The soil becomes hard when dry and its permeability to water and air is reduced.

If irrigation causes sodium salts to accumulate near the soil surface, yields may be reduced. Sodium buildup usually occurs slowly and may not be detected easily from year to year. Excess sodium accumulation in the root zone is a major threat to good productivity on some soils. Include the sodium absorption ratio in your regular soil testing checklist every three to five years to determine long-term trends in sodium accumulation.

The salt (or mineral) content of irrigation water is important for the long-term irrigability of many soils. Irrigation water with large concentrations of salts, when applied to the soil, increases the salt content in the soil because the water is taken up by the plant or evaporates while the salt remains.

To determine the salt content in water, measure the flow of electrical current through a sample of the water. The more dissolved minerals in the water sample, the more easily it conducts electricity, which produces a high electrical conductivity (EC) number.

Distilled water has very high resistance and thus a very low EC, but when the salt content increases, the resistance decreases. The EC has units of deci-Siemens per meter (dS/m), millimhos per centimeter (mmhos/cm) or micromhos per centimeter (umhos/cm).

Here is how to convert from one to the others:

1 dS/m = 1 mmho/cm = 1,000 umhos/cm

The sodium level in the soil in relation to the calcium and magnesium, as well as sodium content in the irrigation water, are important for the long-term productivity and health of the soil. The use of high-sodium water for irrigation depends on the level of salinity (EC) and sodicity in the soil and water.

The measure of the sodium impact is the sodium absorption ratio (SAR), whose units are dimensionless. It is the ratio of sodium concentration to the concentration of calcium and magnesium in soil or water. Generally, soil and water with SARs of less than 6 are acceptable.

The sodicity buildup hazard for irrigation water is dependent on its SAR and salinity. As the salt content of the water increases, the sodicity hazard also increases. This means that lower SARs may cause significant sodium buildup in the soil. The reason for increased sodicity hazard is simply the greater number of sodium ions to replace calcium and magnesium in the soil.

The laboratory-derived SAR may not be a clear indicator of the actual dispersion of clay particles due to increased sodium levels or decreased soluble calcium and magnesium in a soil. A quick field test of suspected areas may help. Place ½ cup of surface soil in a clear glass quart jar, add 1 pint of distilled water and shake well. Leave for an hour undisturbed. If the water has not cleared in that time, the clay has become dispersed and an amendment may need to be applied to keep the surface soil productive.

Sodium accumulation and clay dispersion may be countered by the addition of soluble calcium amendments that replace more weakly held sodium on clay and organic-matter surfaces and increase flocculation (clay particles aggregate into clotlike masses or precipitate into small lumps). Free sodium then can be leached from the soil surface to below the root zone, where it will not interfere with plant growth.

Gypsum, which is the common name for calcium sulfate (CaSO₄), has been used successfully as a reclamation amendment when the soil was not already saturated with gypsum. In areas with low soil salt content, gypsum is the preferred method of reclaiming high-sodium soils.

Gypsum dissolves in the soil, and calcium ions replace sodium ions on clay and organic-matter surfaces. Water moving through the soil then leaches the sodium out of the root zone.

However, in many North Dakota soils, sodium and calcium levels are high together. The addition of gypsum to soils already high in gypsum will not result in a replacement of sodium because greater amounts of gypsum will not increase the number of free calcium ions in solution. Other amendments may be more useful.

For soils with high levels of calcium carbonate and low levels of gypsum, the application of elemental sulfur sometimes is used to produce gypsum. Sulfur is oxidized in soils by sulfur bacteria. The resulting sulfuric acid reacts with calcium carbonate to produce gypsum.

On a few soil series, subsurface gypsum layers can be incorporated into surface soils with high sodium levels through deep tillage. Mixing gypsum into high-sodium soils may be a practical way to reclaim some soils.

Before tillage, soil sampling surface and deep layers with for sodium and gypsum levels will be necessary. If excess gypsum is not present in the subsurface layers, deep tillage may not be helpful.

More soluble calcium amendments, such as calcium chloride, may be more useful in replacing sodium ions in sulfatic systems. Calcium chloride is more soluble in sulfatic systems than gypsum.

The economics of reclamation and effectiveness of amendments in reclaiming sodic soils or countering sodium accumulation should be evaluated before deciding to use soluble calcium and magnesium amendments.

NDSU Soil and Water Testing Laboratory

701-231-8942

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North Dakota State University
Soil and Water Environment Laboratory
NDSU Dept. 7680
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Fargo, ND 58108-6050

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