Soil Conservation: Assessing the National Resources Inventory, Volume 1 (1986)

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Appendix TABLE A Data File Field Definitions and Format in the 1982 NRI Record Location Item and Field on Tape Field Name Description 1 1-5 FIPS code State and county Federal Information Process- ing Standard coder 2 6-12 PSU no. Primary Sampling Unit numbers 3 13 Point no. Specific point within the PSU where inven- tory data are collected—a data record is not included in the NRI file for points that are federal, urban and built-up, transportation facilities, water bodies, or streams3 4 14-17 Location code SCS location coder 5 18-21 ML1lA Major Land Resource Area, per USDA Agri- culture Handbook No. 296 (December 1981)5 6 22-29 Hydrologic unit Water Resource Council hydrologic unit— eight-digit accounting unit number, per U.S. Geological Survey Circular 878-A (1982) 7 30-35 Expansion factor Number of acres the sample point represents (in 100s)—taking into account sampling pro- cedure and state's census acres; for use when constructing acreage estimates (for categories in which the point falls)6 8 36 Ownership of 1 = private land 2 = municipal 3 = county or parish 4 = state 99

100 TABLE A (Continued) APPENDIX Record Location Field on Tape Item and Field Name Description 5 = federal (not in file) 6 = Indian tribal and individual trust lands 0 = not applicable Soils suitability rating for agriculture, between I and VIII—class I soil has few restrictions that limit its use; class VIII soil has limita- tions that nearly preclude its use for com- mercial crop productions Chief limitation of the soil (except when class p: e = erosion; w = water; s = shallow, droughty, or stony; c = climate Soil loss tolerance factor—indicates acceptable level of annual soil loss, between 1 and 5 tons/acre year Meets prime farmland criteria?:8 1 =yes 2 = no Degree of erosion:9 1 = none or slight 2 = moderate 3 = severe Nonarable due to past erosion?:~° 1 = yes 2 = no Presently zeroed out Special management need due to saline and/ 9a 37 Land capability class 9b 38 10 39 11 40 12 41 13 42 14 43 15 44 Saline/alkali Land capability subclass T factor Prime farmland Degree of erosion Nonarable 16 45 Type of irrigation 17 46 Water source 18 47 Water provision or alkali soil?: 1 =yes 2 =no ApplicatiG . of water to soils to assist in pro- duction ~ crops (for 1982, or for at least two of last f; r years): 0 = no irrigation 1 = gravity irrigation 2 = pressure irrigation 3 = gravity and pressure irrigation Source of water for irrigation: 0 = no irrigation 1 = well 2 = pond, lake, or reservoir 3 = perennial stream 4 = lagoon or other waste water 5 = combination Irrigation provides ]/2 of the water require- ments?: 1 = yes 2 = no

APPENDIX TABLE A (Continued) 101 Record Location Item and Field on Tape Field Name Description 48 Flood prone 20 21 22 23 24 26 28 29 30 31 32 33 34 35 36 49 Cover/use general 50 51-53 54-55 56-58 59-61 62-64 65 66-68 69-71 72-74 75-76 77-78 79-81 82-87 88-90 91-94 95-98 Cover/use, major Cover/use, specific Use Cropping history 1 Cropping history 2 Cropping history 3 Double-cropped Flood-prone area?: l2 1 = yes 2 =no General land cover/use based upon specific land cover/use and cropping history: l3 A = cropland B = pastureland and native pasture C = rangeland D = forestland E = other lands (farms) F = barren lands G = other lands H = urban and built-up land I = rural transportation J = water (census) K = small water bodies (noncensus) Codes for major category of used Code by cropl5 Use of land or waterl6 Specific land cover/use for 198117 Specific land cover/use for 1980 Specific land cover/use for 1979 Double-cropping used?:l8 1 =yes 2 = no Conservation Conservation practices that are currently in practice 1 use on the land—up to three practices could be identified; whether the practices were identified in fields 1, 2, or 3 is not relevant to priorityl9 See Conservation practice 1 Conservation practice 2 Conservation practice 3 Conservation need K factor R factor C factor P factor Slope length Slope percent See Conservation practice 1 Conservation treatment needed20 Soil credibility factor for USLE Rainfall factor for USLE Cropping management factor for USLE Erosion-control practice factor for USLE Slope length (in feet) for USLE Slope percent for USLE

102 TABLE A (Continued) APPENDIX Record Location Field on Tape Item and Field Name Description 38 39 40 41 42 43 44 45 46 99 USLE flag 100-103 USLE 106-114 115-120 121-129 132-133 134-135 136-137 USLE tons Wind erosion Wind erosion 130-131 Dominant soil and water problem Secondary soil and water problem Dominant other problem Type of effort necessary 47 138-139 Conversion potential 48 140-141 Type of wetland Modified version of USLE applied: 1 = modified LS, for frozen soil 2 = version for R-1 and R-2 areas 0 = none, or not applicable USLE calculation of estimated average annual soil loss due to sheet and rill erosion (in tons/acre year) Estimated average annual tons of soil loss due to sheet and rill erosion (in lOOs of tons/ acre year) Estimated average annual soil loss due to wind erosion (in tons/acre year) Estimated average annual tons of soil loss due to wind erosion (in lOOs of tons/year) Dominant soil- and water-related problem inhibiting or preventing conversion of land to cropland22 Secondary soil- and water-related problem inhibiting or preventing conversion of land to cropland23 Dominant other problem inhibiting or pre- venting conversion of land to cropland24 Effort necessary for conversion to cropland:25 01 = none: can convert by beginning tillage 02 = on-farm: can convert through actions by individual farmers 03 = multiform: informal or formal coopera- tion between neighbors to install systems 04 = project action required 09 = not applicable, e.g., zero potential 99 = currently cropland, built-up, transporta- tion, or water or Vile, VIIw, VIIs, or class VIII land Potential for conversion to cropland within the foreseeable future: 26 00 = zero potential 01 = conversion unlikely in foreseeable future 02 = medium potential 03 = high potential 99 = currently cropland, built-up, transporta- tion, or water or Vile, VIIw, VIIs, or class VIII soil Wetland type: 00 = not a wetland type 1-20 01-20 = type, as per circular 39, Department of Interior

APPENDIX TABLE A (Continued) 103 Record Location Field on Tape Item and Field Name Kind of vegetation Description Kind of wetland vegetation: 0 = none 1 = emergent 2= scrub/shrub 3 = forested A complex of wetland and deep water habitats influenced by hydrologic, geomorphologi- cal, chemical, and/or biological factors: 0 = no kind 1 = marine 2 = estuarine ~ = Verne 4 = lacustrine 5 = palustrine Kind of riparian area:27 0 = none 1 = natural streambank 2 = man-made canal or ditch bank 3 = natural pond or lake shoreline 4 = man-made pond or reserve* 5 = tidal area shoreline Kind of riparian vegetation: 0 = none (nonriparian area or barren) 1 = trees 2 = shrubs 3 = fortes 4 = grass and grasslike plants 5 = mixed 6 = other Width of the strip of riparian vegetation: 0 = none 1 = less than 100 feet 2 = 100-500 feet 3 = greater than 500 feet Distance from point to nearest occurrence of cropland (in feet); 9999 if nearest occurrence is further than 5,280 teeth Distance from point to nearest occurrence of forestland (in feet) Distance from point to nearest occurrence of pastureland or rangeland (in feet) Distance from point to nearest occurrence of water (in feet) Distance from point to nearest occurrence of wetlands type 1-20 (in feet) 49 142 50 143 Kind of wetland system 51 144 Riparian area kind 52 145 Riparian vegetation 53 146 Riparian width 54 55 56 57 58 147-150 Distance to cropland 155-158 159-162 Distance to forestland Distance to grassland Distance to water 16~166 Distance to wetland

104 TABLE A (Continued) APPENDIX Record Location Item and Field on Tape Field Name Description 59 167-170 Distance to Distance from point to nearest occurrence of built-up farmsteads, urban and built-up, roads, etc. (in feet) 60 171 Winter cover Winter ground cover of the last harvested kind crop: 0 = none or not cropland 1 = live crop 2 = cropland residue Height of crop or residue remaining over winter (in inches) Residue remains upright over winter?: 1 = yes 2 = no 0 = not cropland Pastureland condition rating: 29 2 = good 3 = fair 4 = poor 9 = not applicable 0 = not pastureland Canopy cover of woody plants, if pastureland or native pasture: 1 = 0-10% 2 = 10-25% 3 = 26-55% 4 = 56-100% 0 = not pastureland Rangeland condition rating (percent climax vegetation): 1 = excellent (76-100%) 2 = good (51-75%) 3 = fair (26-50%) 4 = poor (0-25%) 8 = annual range 9 = not applicable 0 = not rangeland Canopy cover of woody plants, if rangeland: 1 = 0-9% 2= 10-25% 3 = 26-55% 4 = 56-100% 0 = not rangeland Apparent trend in condition of the soil and/or vegetation resources, for rangeland: 1 = up (soil and/or vegetation resources . . 1mprovmg 61 172-173 62 174 Winter cover height Upright residue 63 175 Pastureland condition 64 176 Woody canopy cover, for pastureland 65 177 Rangeland condition 66 178 Woody canopy cover, for rangeland 67 179 Rangeland condition trend

APPENDIX TABLE A (Continued) 105 Record Field on Tape Location Item and Field Name Description 68 180 Grazing level, for rangeland 69 181 70 182-184 Forest type, general Forest type, specific 71 185 Canopy cover, for forestland 72 186-188 Basal area/stem count 73 189-191 74 192 DBH Forest understory composition 75 193 Understory forage value 76 — Soils-5 2 = even (not readily apparent) 3 = down (resources deteriorating) 0 = not rangeland Status of grazing, for rangeland: 1 = not routinely grazed 2 = routinely grazed but presently deferred 3 = currently grazed, lightly to properly used 4 = currently grazed, excessively used 0 = not rangeland General category of forest cover type (blank if not forest)30 Specific category of forest cover type Canopy cover of trees, for forestland: 1 = 0-9% 2= 10-25% 3 = 26-55% 4 = 56-100% 0 = not forestland Basal area of the stand (in square feet per acre), if average diameter at breast height (OBH) is at least 5 inches; if less than 5 inches, then stocking based on stem count is given: 900 = poorly stocked 901 = moderately stocked 902 = fully stocked 000 = nonstocked or not forestland Average DBH, for forestland (in inches) Primary plant group for forestland understory composition: 0 = none 1 = woody 2 = fortes 3 = grass and grasslike plants Forage value rating of understory for forest- land, based upon percentage of understory production by preferred species: 1 = very high (51-100%) 2 = high (31-50%) 3 = moderate (11-30%) 4 = low (0-10%) 9 = not applicable, i.e., not suitable for grazing 0 = not forestland Soils-5 identification block; not standard field on NRI data filed SOURCE: 1982 NRI.

106 Notes to Appendix APPENDIX iThe Federal Information Processing Standard (PIPS) code identifies the state and county in which the sample point falls. 2The Primary Sample Units (PSUs) compiled by the Iowa State University Statistical Laboratory were located by field personnel on aerial photographs. The PSUs were then examined to determine if the inventory could proceed based on existing soil surveys or if old surveys should be updated or new surveys made. Boundaries of the PSUs were transferred to the most recent aerial photograph on which soil characteristics had been mapped. Most PSUs have three sample points, although smaller (40-acre) PSUs have only one. The locations of these points were given on a gummed label sent from the Iowa State University Statistical Laboratory. Two coordinates were given to locate each point. 4Internal SCS code for use with time and progress reporting system. 5The United States is divided into 156 Major Land Resource Areas (MLRAs), some of which are further divided into subareas denoted by letters (i.e., MLRA 83A is the north- ern Rio Grande Plain, 83B is the western Rio Grande Plain, and so forth). Expansion factors were assigned by the Iowa State University Statistical Laboratory. This factor specifies the number of acres that the sample point represents for constructing acreage estimates for categories in which the point falls. Fields 8 to 39, 41, and 43 to 76 describe characteristics of the point. When estimated erosion rates are expanded to geographic aggregates larger than the land represented by the sample point, use fields 40 and 42. 7The Land Capability Class System (LCCS) is described in Agriculture Handbook No. 210, SCS, USDA. Prime farmland is land that has the best combination of physical and chemical charac- teristics for producing food, feed, forage, fiber, and oilseed crops and is also available for these uses (the current use could be cropland, pastureland, rangeland, forestland, or other land, but not urban built-up land or water). Specific criteria for prime farmland are given in the Federal Register, Vol. 43, No. 21, January 31, 1978. 9Degree of erosion: (1) None or slight—Accelerated erosion has not greatly altered the thickness and character of the A horizon. There may be a few rills, some deposits of windblown sediment near plants or clods or places with thin A horizons that indicate slight accelerated erosion is taking place. (2) Moderate—Accelerated erosion has reduced the thickness and character of the A horizon. In cultivated areas, erosion has removed enough of the original A horizon so that tillage or other implements have mixed the original A horizon and underlying horizons. In uncultivated areas, approximately 25 to 75 percent of the original surface soil has been removed by erosion from most of the area. There may be a few shallow gullies, scoured or blown-out areas, or evidence of soil drifting. (3) Severe—The soil has been eroded to the extent that all or practically all of the original surface soil has been removed. The surface layer consists essentially of materials from the B horizon or other underlying horizons. Severe Sullying, scouring, drifting, or dune development is included. Dyes is answered if past erosion had changed land formerly suitable for cropland to marginally suitable or unsuitable for cropland use. This question was answered for all land uses and types of vegetative cover. VIA saline soil interferes with the growth of most crop plants, because of high salt content. An alkali soil reduces the growth of most crop plants because of high sodium or high salt and sodium. Such soils require special management practices and measures for reclamation. Flood-prone areas adjoin rivers, streams, watercourses, bays, lakes, alluvial fans and plains, or other areas that in the past have been covered intermittently by floodwater or could be expected to be flooded in the future. Upland depressions are not included.

APPENDIX 107 Flood-prone areas are the approximate areas subject to inundation by a flood having an average recurrence interval of once in 100 years (floods having a 1 percent chance of occurring in any given year). The area was to be determined on the basis of sound engineering analyses where available and on interpretative analyses where engineering analyses are not available. Sources of information included studies by the SCS, the Corps of Engineers, and the U.S. Department of Housing and Urban Development and maps prepared by the U.S. Geological Survey, the Tennessee Valley Authority, and the National Oceanic and Atmospheric Agency. General land cover/use in 1982 is coded in field 20 as follows: A, cropland/hayland; B. pastureland, native pasture; C, rangeland and tundra; D, forestland; E, other land in farms; F. barren land; G. other lands; H. urban and built-up, small built-up; I, rural transportation; J. water, census; K, water body, smaller than 40 acres. In cases where the point fell on a land cover/use boundary, field personnel first tried to identify the land cover/use to the north of the point. If this also was a boundary, the land cover/use to the east of the point was recorded. The same rule was applied if the point fell on a fence row or a narrow waterway. Infield 21 contains the next level of land cover/use classification, an alphabetic code for major land cover/use. The letter A will appear in this field for all pastureland and native pasture, rangeland and tundra, forestland, other land in farms, barren land, other lands, rural transportation, and census-sized water areas. For cropland, urban and built-up land, and small water bodies, however, field 21 will contain one of the following alpha- betic codes for major land cover/use. For cropland: A, horticultural crops; B. row crops; C, close-grown crops; 1), hayland; E, other. For urban and built-up: A, urban/built-up (less than 10 acres); B. small built-up (0.25-10 acres). For water body: A, water body smaller than 40 acres; B. small perennial stream. 75~iS and other codes can be found in the 1982 NRI field documentation guide (SCS, USDA). lathe numeric code entered in this field reflects the primary or dominant use of land, regardless of land cover/use recorded above. For example, in a rural park, the land cover/ use item may be forests, not grazed (coded 342 in field 22), but the use of the land would be recorded as recreation (43) in field 23. Infields 24, 25, and 26 specify land cover/uses for 1981, 1980, and 1979, respectively. The same codes are used here as in field 22 (see note 15~. For example, if the land was in continuous rangeland cover/use, the numeric code 250 would appear in each of these fields. A 1979-1981 cropping history of corn, soybeans, and corn would be coded in these fields as 011, 013, and 011, respectively. Information on crop rotations was used in the Wind Erosion Equation and Universal Soil Loss Equation (USLE). Including the entry for the current (1982) crop, four years of cropping history are available altogether. ~8This field applies to cropland that was used for horticultural, row, or close-grown crops. No was entered for all other land cover/use codes, including water. If information for the current year (1982) was limited, the entry reflects a history of double-cropping in the field for two or more years out of the last four years. Hay and pasture was not considered double-cropped. Infields 28 to 30 record up to three conservation practices in use in 1982. The practices must have been applied to the area in which the point fell or in the portion of the field surrounding the point that would be used for conservation planning. The point need not have fallen on the specific practice to be recorded. For example, if a point fell on a farmstead that had a farmstead and feedlot windbreak, code 380 should appear in field 28. If none of the listed practices were encountered, 000 should be entered for each field. If only one practice was in use, it is coded in field 28 and the other fields should show 000. Whenever terraces are coded (600) for one field, it is presumed that contour farming was in use, so code 330 should appear in another of the three fields.

108 APPENDIX 20The data were obtained for the area in which the point fell or for the portion of the field surrounding the point that would be used in conservation planning. Conservation needs were based on the judgment of a qualified specialist or technician as guided by the local technical guide, prevailing agricultural operations, and the practical bases and guides used and exercised in the development of conservation plans. Primary or dominant treatment needs were recorded. Field personnel were instructed to give erosion control treatment needs priority over other needs such as treatment to increase wood or forage production. 2iFields 32 to 37 contain values for the six factors in the USLE. Instructions referred field personnel to local technical guides, SCS Technical Service Center publications, and Agriculture Handbook No. 537 (December 1978) for detailed explanation of factors in the USLE. Determinations were made for the field in which the point fell or the portion of the field surrounding the point that would be used in conservation planning. Field 32: K factor. The credibility factor for the soil series. Specialists were to estimate K factors for mapping units that were complexes, associations, undifferentiated units, or miscellaneous land types or for mapping units above the soil series level. Field 33: R factor. The current rainfall factor map was used. Where appropriate— mainly in the Pacific Northwest—a thaw-snowmelt adjustment was included. This adjustment is encoded in field 38. Field 34: C factor. The cropping management factor reflects crop sequence and resi- due for cropland. Areas in pastureland, rangeland, and forestland coverluses reflect a different extension of the factor than cropland. Percent ground cover was determined from a perpendicular view. Field 35: P factor. The value for the erosion control practice factor was entered from Tables 13, 14, and 15 of Agriculture Handbook No.537. If the value in this field is less than 1.0, the value and then a code of either 330 (contour farming) or 585 (contour stripcrop- ping) should be entered in fields 28 to 30. Field 36: Slope length. The length of slope (in feet) through the point. On terraced land, the distance between terraces was entered. Slope length is the distance from the point of origin (whether on or off the PSU) of overland flow to either of the following: (1) the point where the slope decreases to the extent that deposition of sediment begins or (2) the point where runoff enters an area of concentrated flow or a channel. Field 37: Percent slope. Rounded to the nearest percent on slopes greater than 1 percent and to the nearest 0.1 percent on slopes of less than 1 percent. Zero should not appear. Slope percent was measured on the segment of the land form on which the point fell and in the direction that water would flow overland. 22Fields 43 to 47 are coded 99 if the land at a sample point was urban and built-up, rural transportation land, water, or had a land cover/use of cropland; capability class and subclass Vile, VIIw, or VIIs; or capability class VIII. If the point is not coded 99, personnel determined the dominant reason that would inhibit or prevent conversion of the land to cropland. 23The same code as used in field 25 is used here to record secondary soil and water problems that would inhibit or prevent conversion of land to cropland. Bother reasons that would inhibit or prevent conversion of land to cropland were of a social, economic, or environmental nature. 25The type of effort necessary for conversion to cropland was determined to provide a relative measure of the magnitude and time that might be involved in converting land to cropland. 26Upon completion of the determinations encoded in fields 25 to 28, SCS personnel met with representatives from other agricultural agencies in the county, including the Agri- cultural Stabilization and Conservation Service, Economic Research Service, Farmers Home Administration, and the Forest Service. The group determined for each point the

APPENDIX 109 potential for conversion to cropland within the forseeable future (10 to 15 years). Deter- minations were teased on commodity prices, development costs, and production costs for the year prior to the current year. High potential was to be assigned in cases where similar land had been converted to cropland during the preceding three years. Lands held for urban or related development were excluded from medium and high potential. 27A riparian area was defined as the bank, shoreline, or edge of the rising ground bordering a natural or constructed watercourse or a water area (lake or tidal area, for example). Riparian was not limited to natural areas. 28Fields 54 to 62 contain data with which to relate wildlife habitat to land cover, use of an area, and diversity of an area in which the sample point fell. For fields 54 to 59, 0 was entered if the point fell in the respective diversity types. Diversity was not shown beyond 5,280 feet (1 mile) from the sample point. If a given diversity type either did not exist or was beyond 5,280 feet, the field should be coded 9999. 29Definition of codes for rating pastureland and native pasture are as follows: 2—Good. Best suited plants are being used. There is moderate- to high-level fertility and good to excellent grazing management. Grazing is at an intensity for maximum plant production and vigor. 3—Fair. A moderate level of management is being used. Plants are adapted to cli- mate and soils but not necessarily for the best designated use. Grazing is at an intensity that limits production to moderate levels. Erosion is minimal. Fertilization is irregular and unplanned. A continuous grazing system is in use. 4—Poor. There is improper pasture use or a low level of management, or plants are not well suited to climate and soil. The soil has a low fertility level and evidence of erosion. Brush management may be necessary. 9—Not applicable. Production is by native species not routinely fertilized, over- seeded, or irrigated. 30The point was considered forestland if trees were recently harvested but not currently stocked or committed to some other use. Fin Chapter 2 the committee recommends that a supplementary tape be issued con- taining the Soils-5 identification code and that future inventories contain these data.