Battaglin, W.A., and Goolsby, D.A.
1994
Estimates of agricultural-chemical use in counties in the conterminous United States as reported in the 1987 Census of Agriculture
1.0
Series_Name WRIR-94 Issue_Identification 4176
Lakewood, CO
USGS
http://water.usgs.gov/lookup/getspatial?ag_chem
This coverage contains estimates of agricultural-chemical use in counties
in the conterminous United States as reported in the 1987 Census of
Agriculture (U.S. Department of Commerce, 1989a). Agricultural-chemical use
data are reported as either acres on which used, tons, or as a percentage
of county area. Agricultural-chemical use estimates were generated from
surveys of all farms where $1,000 or more of agricultural products were
sold, or normally would have been sold, during the census year.
Most of the attributes summarized represent 1987 data, but some
information from the 1982 Census of Agriculture also was included.
The polygons representing county boundaries in the conterminous United
States, as well as lakes, estuaries, and other nonland-area features were
derived from the Digital Line Graph (DLG) files representing the
1:2,000,000-scale map in the National Atlas of the United States (1970).
Agricultural chemicals
Census of Agriculture
Counties
United States
The agricultural-chemical use data in this coverage are intend for use
in estimating regional agricultural-chemical use, and in producing visual
displays and mapping relative amounts of agricultural-chemical use across
broad regions of the United States.
Procedures_Used:
CENSUS DATA
An automated procedure was developed for processing the raw
census data into ARC/INFO coverage attributes. The procedure is
summarized below:
1) copy county2m coverage to coverage representing type of census
data (i.e. ag_expn or ag_land),
2) run agadd.aml for each item added to the coverage, giving
coverage name and attribute field number as arguments.
The agadd.aml program runs a fortran program to extract field data
from the raw census data files, and then processes that raw data
finally adding it as a column of attribute data to the county coverage.
Other programs were developed to calculate summary statistics of
the census attribute data, and to make graphics representing
attribute values across the United States.
COUNTY BOUNDARIES
This series of maps was published as part of the National Atlas of the
United States (U.S.Geological Survey, 1970). The maps for the conterminous
United States were digitized in 15 sheets and published in the Digital
Line Graph (DLG) format as described by Domeratz and others (1983).
Each sheet was prepared by reading the DLG files of the political and
water bodies layers, converting them to ARC/INFO, extracting the county
boundaries and the coastline, respectively, and joining the two layers.
FIPS codes were assigned to all polygons by using available sources and
were checked manually.
Boundaries with adjacent sheets of the 15-sheet set were edgematched
manually, arbitrarily choosing one of the sheets as the "correct" border.
Edgematching operations adjusted the linework as far as was necessary so
that the coverages would fit to a tolerance of 100 meters. The coverage
(referred to herein as Version 1.0) was stored as 49 separate coverages
(48 States and the District of Columbia) because the ARC/INFO software in
use at the time could not process the entire coverage. Individual States
could be joined by specifying a tolerance of 100 meters.
From time to time, adjustments were made to the State coverages to
reflect changes in U.S. counties. It is believed the accuracy of
these adjustments is comparable to the original linework.
For Version 2.0, all State coverages were rejoined and manually edited
to produce a perfect edgematch between all States. For States on the
original map sheet boundaries, this adjustment averaged less than 20
meters and in no case was more than 100 meters. The whole coverage was
CLEANed to a tolerance of 20 meters, which resulted in few, if any,
effects on small offshore islands. The coverage also was checked to ensure
that it represented current U.S. counties or county equivalents.
The coverage in Version 1.0 stopped at the coastline. There was no
attempt to depict offshore areas. This created some problems when the
coverage was used to assign county codes to sampling stations located near
the coast. To help in this matter, Version 2.0 includes offshore
extensions of the county polygons. The (water) boundaries of many of these
polygons are arbitrary.
The Canadian Great Lakes features are another new addition to
Version 2.0. They were added to improve the utility of the coverage for
visual displays. Although the Canadian Great Lakes are logically
represented by a single polygon, practical considerations -- the inability
of some software to plot polygons with a large number of vertices -- made
it necessary to separate them into four polygons. The dividing lines are
located in narrow channels to minimize interference with plotting
patterns. Canadian islands within the Great Lakes also were included.
All ticks were relocated to places that are easily visible on maps of
the United States, to help in registering maps that may not otherwise
have adequate registration information.
To expedite accessing parts of the coverage, certain items have been
indexed with the procedure, INDEX_COUNTY.AML. See Section 3 above. A
spatial index also was created.
When using this coverage to clip or intersect other coverages, a
tolerance as low as 2 meters can be used.
The processing used to derive this coverage moved boundaries from their
positions on the original maps. In cases of conflicting lines, preference
was given to forming the correct topology. Strictly speaking, this
coverage is not identical to the source materials. These changes were
unavoidable in producing a continuous coverage of the conterminous
United States.
Revisions:
COUNTY POLYGON DATA
Revision 1.0, 12/17/90. This revision represents numerous
corrections and minor modifications made to this set of coverages
from its construction in 1985 through the revision date.
Process_Date 12/17/90
Revision 2.0, 3/18/91. Major reworking of the coverage, combining
all State coverages.
Process_Date 3/18/91
Reviews_Applied_to_Data:
The Census of Agriculture data processing procedure and attribute
data have been peer reviewed in 1993 by Leonard Orzol and Barbara Ruddy,
both hydrologist with the USGS.
The county boundaries in this coverage have received no formal review.
They have, however, been used in numerous applications where serious
errors would have been obvious. Some State coverages were corrected
following such use. The offshore polygon extensions and the Canadian
Great Lakes polygons have had no review.
Related_Spatial_and_Tabular_Data_Sets:
This coverage is part of series of 1:2,000,000-scale base maps
covering the United States. Layers in this set include:
COUNTY -- County boundaries.
STATE -- State boundaries (formed from COUNTY).
WATERBOD -- Water Bodies.
STREAM -- Streams.
HUC -- Hydrologic cataloging units (basins).
Other_References_Cited:
Domeratz, M. A., Hallam, C. A., Schmidt, W. E., and Calkins, H. W., 1983,
USGS Digital Cartographic Data Standards: Digital Line Graphs from
1:2,000,000-scale Maps. U.S. Geological Survey Circular 895-D, 38p.
Nebert, Douglas D., 1994, Design of the distributed spatial data library
for the Water Resources Division, U. S. Geological Survey: U. S.
Geological Survey Open-File Report, 94-327, 30 p.
U.S. Department of Commerce, 1989a, Census of agriculture, 1987 -- Final
county file: U.S. Department of Commerce, Bureau of the Census,
[machine-readable data file]
U.S. Department of Commerce, 1989b, Census of agriculture, 1987 -- Final
county file technical documentation: U.S. Department of Commerce,
Bureau of the Census, Data User Services Division.
U.S. Department of Commerce, 1990, Census of agriculture, 1987 --
Agricultural atlas of the United States, volume 2: U.S. Department
of Commerce, Bureau of the Census, Agriculture Division, AC87-S-1,
210 p.
U.S. Geological Survey, 1970, National atlas of the United States
of America: Washington D.C., U. S. Geological Survey, 417 p.
Notes:
DOCUMENTATION
The documentation for this coverage was generated by using the ARC
macro language (AML) program document.aml available from the U.S.
Geological Survey (Nebert, 1994).
0000
(Here you put information defining how the time period of
content information, on the DOC file, was determined)
As Needed
-128.07002717
-65.25698378
48.26194027
22.67774911
None
Agricultural chemical use in counties from 1987 Census of Agriculture
inlandWaters
None
Conterminous United States
None
None
None
None
(describe any restrictions or legal prerequisites for accessing
the data set. Put "None" if there are no restrictions)
CENSUS DATA
Estimates of agricultural-chemical use by county were reported by the
U.S. Department of Commerce (1989a, 1898b) in the 1987 Census of
Agriculture. The estimates were constructed from surveys of all farms where
$1,000 or more of agricultural products were sold, or normally would have
been sold, during the census year. Sampling and statistics were used to
account for nonresponding farm operations. Thus, the information in the
Census of Agriculture is subject to sampling variability as well as
reporting and coverage errors.
Census disclosure rules prevent publication of information that would
disclose the operation of individual farms. Thus, for example, one or two
sod farms may be reported in a county, but no acreage of sod harvested is
reported, because release of that information might disclose information
about a particular farmer's operation.
COUNTY BOUNDARIES
The original files for this map were provided in 15 sections. Boundaries
near the edges of sections have been adjusted in edgematching.
Polygons that extend into the water (an ocean or the Great Lakes) should
be considered arbitrary.
William A. Battaglin
U.S. Geological Survey, Water Resources Div. (WRD)
Hydrologist, Office of the Regional Hydrologist
mailing address
P.O. Box 25046, Denver Federal Center, Bldg. 25
Lakewood
CO
80225
USA
1-888-275-8747
303-236-5959
wbattagl@usgs.gov
8:00am-4:30pm MST
Please contact thru email
http://water.usgs.gov/GIS/browse/ag_chem.gif
Illlustration of data set
GIF
(Here you acknowledge the agencies and organizations that gave
you money, resources, and encouragement to digitize the data and
to enter all this wonderful metadata.)
None
Unclassified
None
dgux, 5.4R3.10, AViiON UNIX, ARC/INFO version 7.0.4
See Entity_Attribute_Information
See Explanation
Attribute accuracy is described, where present, with each
attribute defined in the Entity and Attribute Section.
Polygon and chain-node topology present.
(Information in wordy narrative form describing omissions,
selection criteria, generalization, definitions used, and other
rules applied to derive the data set)
(An explanation of the accuracy of the horizontal coordinate
measurements and a description of tests used, if any, to
determine horizontal positional accuracy. This is different
from horizontal resolution as reported in the DOC file.
Positional accuracy defines how correctly the digital features
match real-world features and woiuld be related to the concept
of the National Map Accuracy Standard -- xx% of well-defined
point features fall within xx units of their true position.
The resolution is the smallest unit of measure the GIS can
reliably manage without truncation or rounding.)
approx. 1.0 km.
Resolution as reported
(The same as above, but for vertical information that may
be encoded with the 2-D features such as cell or contour
estimates of a vertical dimension. A description of the
contour interval of input data and its basis could be described
here.)
Unspecified
0000
Unspecified
2,000,000
Unspecified
0000
Unspecified
Unspecified
Unspecified
RESELECT COUNTY2M COUNTY.NEW POLY
None
19911112
1528
None
LABELERRORS COUNTY.NEW
None
19911112
1529
None
LABELERRORS COUNTY.NEW
None
19911112
1556
None
EXTERNALALL
None
19911112
1721
None
RENAME COUNTY.NEW COUNTY2M
None
19911113
1249
None
CREATELABELS COUNTY2M 5000
None
19911115
1656
None
EXTERNALALL
None
19911204
1410
None
COPY COUNTY2M /ARC3/WORK/LIB/COUNTY2M
None
19920102
0833
None
COPY /ARC3/WORK/LIB/COUNTY2M COUNTY.AG
None
19920102
1527
None
RENAME COUNTY.AG CNTY.AG
None
19920102
1527
None
COPY /ARC3/WORK/CNTY.AG COUNTY2M
None
19920107
1423
None
EXPORT COVER COUNTY2M COUNTY2M
None
19920117
1350
None
COPY /ARC3/WORK/LIB/COUNTY2M COUNTY2M
None
19920121
1549
None
BUILD COUNTY2M POLY
None
19920121
1615
None
ARCEDIT /ARC3/WORK/COUNTY2M
None
19920122
0948
None
BUILD COUNTY2M POLY
None
19920122
0956
None
IDEDIT COUNTY2M POLY
None
19920122
1101
None
COPY COUNTY2M /ARC3/WORK/LIB/COUNTY2M
None
19920122
1102
None
IDEDIT COUNTY2M POLY
None
19920330
1537
None
EXPORT COVER COUNTY2M COUNTY2M
None
19920608
1103
None
ARCEDIT /ARC3/WORK/LIB/COUNTY2M
None
19920803
1748
None
BUILD COUNTY2M POLY
None
19920803
1758
None
CLEAN COUNTY2M # 2 2 POLY
None
19920803
1846
None
COPY COUNTY2M /WB2/DB/USA/COUNTY2M
None
19920804
0919
None
COPY /WB2/DB/USA/COUNTY2M AG_CHEM
None
19930104
1648
None
DOCUMENT AG_CHEM DELETE WBATTAGL
None
19930329
0947
None
DOCUMENT AG_CHEM UPDATE WBATTAGL
None
19930329
1049
None
DOCUMENT AG_CHEM UPDATE WBATTAGL
None
19930329
1118
None
DOCUMENT AG_CHEM UPDATE WBATTAGL
None
19930329
1350
None
EXPORT COVER AG_CHEM AG_CHEM
None
19930330
1041
None
COPY /ARC3/EPA1/CENSUS/AG_CHEM AG_CHEM
None
19941227
1317
None
PROJECTDEFINE COVER AG_CHEM
None
19941227
1318
None
DOCUMENT AG_CHEM UPDATE WBATTAGL
None
19941227
1500
None
DOCUMENT AG_CHEM UPDATE WBATTAGL
None
19941230
1125
None
MNEGRI IMPORT COVER AG_CHEM.E00 AG_CHEM
None
19950307
1009
None
Unspecified
None
19950307
1022
None
MNEGRI EXPORT COVER AG_CHEM AG_CHEM.E00
None
19950309
1510
None
MNEGRI EXPORT COVER AG_CHEM AG_CHEM.E00
None
19950309
1524
None
MNEGRI ARCSDTS AG_CHEM AG_CHEM.TAR.GZ PREF
None
19950309
1540
None
MNEGRI EXPORT COVER AG_CHEM /SCRATCH_AREA1/MNEGRI/AG_CHEM.E00 NONE
None
19950919
1453
None
MNEGRI EXPORT COVER /DSDL1/CUSA/TILES/CUSA/AG_CHEM AG_CHEM.E00
None
19960624
0814
None
MNEGRI EXPORT COVER /DSDL1/CUSA/TILES/CUSA/AG_CHEM AG_CHEM.E00
None
19960625
1044
None
Vector
Point
4787
String
11926
GT-polygon composed of chains
4788
Albers Conical Equal Area
29.5
45.5
-96
23
0.0
0.0
coordinate pair
1.0
1.0
METERS
Unknown
Clarke 1866
6378206.4
294.98
AG_CHEM.PAT
Polygon attribute table
ARC/INFO file
AREA
Area of polygon in square coverage units (meters)
Computed
Positive real numbers
unspecified
unspecified
PERIMETER
Perimeter of polygon in coverage units (meters)
Computed
Positive real numbers
unspecified
unspecified
AG_CHEM#
Internal feature number
Computed
Sequential unique positive integer
unspecified
unspecified
AG_CHEM-ID
User-assigned feature number
User-defined
Integer
unspecified
unspecified
FIPS
5-digit County FIPS code
Federal Information Processing Standard
01001 - 56998, none = 0
unspecified
unspecified
ST
two-character state abbreviation
U.S. Postal Service
AL - WY, none = blank
unspecified
unspecified
CNTYNAME
County name
U.S. Geological Survey Files
upper-case alphanumeric, none = blank
unspecified
unspecified
PLYTYPE
polygon type: 0=county land, others are lakes, estuaries, etc.
see narrative
0-4,9
unspecified
unspecified
WORKB
variable used for data processing
n/a
any integer
unspecified
unspecified
AREA.ACRES
total county land area (all polygons) in acres
calculated from areas of polygons with like FIPS code and PLYTYPE=0
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0772
Commercial fertilizer, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0772
Percent of county treated with commercial fertilizer, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0773
Commercial fertilizer, 1982 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0773
Percent of county treated with commercial fertilizer, 1982
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0776
Cropland fertilized, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0776
Percent of county as cropland fertilized, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0777
Cropland fertilized, 1982 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0777
Percent of county as cropland fertilized, 1982
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0780
Pastureland and rangeland fertilized, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0780
Percent of county as pastureland and rangeland fertilized, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0784
Lime, 1987 (acres on which used)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0784
Percent of county treated with lime, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0786
Lime, 1987 (tons)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
CA0790
Chemicals used to control insects on hay and other crops, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0790
Percent of county treated to control insects on hay and other crops, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0791
Chemicals used to control insects on hay and other crops, 1982 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0791
Percent of county treated to control insects on hay and other crops, 1982
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0794
Chemicals used to control nematodes in crops, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0794
Percent of county treated to control nematodes in crops, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0795
Chemicals used to control nematodes in crops, 1982 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0795
Percent of county treated to control nematodes in crops, 1982
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0798
Chemicals used to control diseases in crops and orchards, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0798
Percent of county treated to control diseases in crops and orchards, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0799
Chemicals used to control diseases in crops and orchards, 1982 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0799
Percent of county treated to control diseases in crops and orchards, 1982
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0802
Chemicals used to control weeds or grasses in crops, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0802
Percent of county treated to control weeds or grasses in crops, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0803
Chemicals used to control weeds or grasses in crops, 1982 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0803
Percent of county treated to control weeds or grasses in crops, 1982
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0806
Chemicals used for defoliation or growth control in crops, 1987 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0806
Percent of county treated for defoliation or growth control in crops, 1987
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
CA0807
Chemicals used for defoliation or growth control in crops, 1982 (acres)
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99
unspecified
unspecified
PCT0807
Percent of county treated for defoliation or growth control in crops, 1982
U.S. Department of Commerce, 1989a
numeric values greater than 0, missing = -99.000
unspecified
unspecified
FIPSST
two-digit state FIPS code
Federal Information Processing Standard
01 - 56, none = 0
unspecified
unspecified
FIPSCNTY
three-digit county FIPS code
Federal Information Processing Standard
001 - 998, missing = 0
unspecified
unspecified
AG_CHEM.AAT
Line attribute table
ARC/INFO file
FNODE#
Internal number of from-node
Computed
Sequential unique positive integer
unspecified
unspecified
TNODE#
Internal number of to-node
Computed
Sequential unique positive integer
unspecified
unspecified
LPOLY#
Internal number of polygon to left of arc
Computed
Sequential unique positive integer
unspecified
unspecified
RPOLY#
Internal number of polygon to right of arc
Computed
Sequential unique positive integer
unspecified
unspecified
LENGTH
Length of arc in coverage units (meters)
Computed
Positive real numbers
unspecified
unspecified
AG_CHEM#
Internal feature number
Computed
Sequential unique positive integer
unspecified
unspecified
AG_CHEM-ID
User-assigned feature number
User-defined
Integer
unspecified
unspecified
BNDTYPE
boundary type
see narrative
0-8
unspecified
unspecified
CENSUS ATTRIBUTES
All census attributes were extracted from tabular data files provided
by the U.S. Department of Commerce (1989a). Data are reported in either
thousands of dollars, number, acres, or percent of county. Attribute names
are keyed to field names found in the technical documentation of the
the Census of Agriculture (U.S. Department of Commerce, 1989b).
Specifically, the four-digit number at the end of the ARC/INFO item name
matches the field-name numbers in the technical-documentation reference.
Complete definitions of attributes and terms used in the census can be
found in U.S. Department of Commerce (1989b; 1990).
Thirty-three attributes from the 1987 Census of Agriculture were added
to an ARC/INFO coverage of agricultural-chemical use estimates. The
coverage name, attribute names, and short attribute descriptions are
listed in table 1. Attribute names beginning with CA represent data fields
transferred directly from the census tabular data files. Attribute names
beginning with PCT are percent-of-county attributes, and represent
relative intensities of an agricultural practice. Attributes reported as
percent of county were calculated as the attribute value (in acres)
divided by the county polygon area (in acres) multiplied by 100.
Table 1. 1987 Census of Agriculture agricultural-chemical use estimates
coverage name, attribute names, and short attribute descriptions
___________________________________________________________________________
AG_CHEM--Coverage of agricultural-chemical use estimates from the
1987 Census of Agriculture
___________________________________________________________________________
Attribute name Description
___________________________________________________________________________
CA0772 Commercial fertilizer, 1987 (acres on which used)
PCT0772 Percent of county treated with commercial
fertilizer, 1987
CA0773 Commercial fertilizer, 1982 (acres on which used)
PCT0773 Percent of county treated with commercial
fertilizer, 1982
CA0776 Cropland fertilized, 1987 (acres on which used)
PCT0776 Percent of county as cropland fertilized, 1987
CA0777 Cropland fertilized, 1982 (acres on which used)
PCT0777 Percent of county as cropland fertilized, 1982
CA0780 Pastureland and rangeland fertilized, 1987
(acres on which used)
PCT0780 Percent of county as pastureland and rangeland
fertilized, 1987
CA0784 Lime, 1987 (acres on which used)
PCT078 Percent of county treated with lime, 1987
CA0786 Lime, 1987 (tons)
Sprays, dusts, granules, fumigants, and other compounds use to control --
CA0790 Insects on hay and other crops, 1987
(acres on which used)
PCT0790 Percent of county treated for insects on hay and
other crops, 1987
CA0791 Insects on hay and other crops, 1982
(acres on which used)
PCT0791 Percent of county treated for insects on hay and
other crops, 1982
CA0794 Nematodes in crops, 1987 (acres on which used)
PCT0794 Percent of county treated for nematodes in
crops, 1987
CA0795 Nematodes in crops, 1982 (acres on which used)
PCT0795 Percent of county treated for nematodes in
crops, 1982
CA0798 Diseases in crops and orchards, 1987
(acres on which used)
PCT0798 Percent of county treated for diseases in crops
and orchards, 1987
CA0799 Diseases in crops and orchards, 1982
(acres on which used)
PCT0799 Percent of county treated for diseases in crops
and orchards, 1982
CA0802 Weeds, grass, or brush in crops and pasture, 1987
(acres on which used)
PCT0802 Percent of county treated for weeds, grass, or
brush in crops and pasture, 1987
CA0803 Weeds, grass, or brush in crops and pasture, 1982
(acres on which used)
PCT0803 Percent of county treated for weeds, grass, or
brush in crops and pasture, 1982
CA0806 Chemicals used for defoliation or for growth control of
crops or thinning of fruit, 1987 (acres on which use
PCT0806 Percent of county treated with chemicals used for
defoliation or for growth control of crops or
thinning of fruit, 1987
CA0807 Chemicals used for defoliation or for growth control of
crops or thinning of fruit, 1982 (acres on which use
PCT0807 Percent of county treated with chemicals used for
defoliation or for growth control of crops or
thinning of fruit, 1982
_________________________________________________________________________
Census estimates for counties represented by one polygon are equal to
county totals. For counties described by more than one polygon,
attribute values are provided for each polygon and are calculated as
the county total multiplied by the ratio of the area of each county
polygon divided by the total area of the county.
A missing-value code of -99 is used when no census-attribute data are
given for a county, and for all nonland-area polygons. A missing-value
code in a county land polygon could indicate any of the following
condition:
--agricultural practice not present in county (for example, no corn
grown in county)
--data withheld because of census disclosure rules
--data not available to census
--data not published because county contains less than 10 farms
--data not applicable
COUNTY POLYGON ATTRIBUTES
Each county is identified by a five-digit Federal Information
Processing Standard (FIPS) code. The first two digits represent
the state and the three remaining represent the county within State.
County names (in upper case) and the two-character State
abbreviation also are included.
All polygons are coded by polygon type (PLYTYPE) as follows:
0 = U.S. land.
1 = Extensions of counties into the ocean and estuaries.
Some boundaries may be arbitrary.
2 = U.S. Great Lakes. Some boundaries between counties may
be arbitrary.
3 = Canadian Great Lakes.
4 = Canadian islands in Great Lakes, included for visual
cartographic purposes.
9 = External polygon.
All arcs are coded by boundary type (BNDTYPE) as follows:
0 = Coastline of United States.
1 = State-State border occurring on land.
2 = County-county border, within state, occurring on land.
3 = State-State border occurring on the ocean, an estuary,
or a Great Lake. Some of these borders are arbitrary.
4 = County-county border, with State, but occurring on the
ocean, an estuary, or a Great Lake. Some of these
borders are arbitrary.
5 = International border occurring on land.
6 = International border occurring on water.
7 = Canadian shoreline of the Great Lakes.
8 = Arbitrary separation line between the Canadian portions
of the Great Lakes.
9 = Closure line with the external polygon. This is
arbitrary.
All BNDTYPE values are determined from the adjoining polygons by
the routine, INDEX_COUNTY.AML. The coverage is indexed (ARC:
INDEXITEM) on FIPS code, State FIPS code, State abbreviation,
county name, polygon type, and boundary type.
Not Available
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mailing
445 National Center
Reston
VA
20192
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Although this data set has been used by the U.S. Geological
Survey, U.S. Department of the Interior, no warranty expressed or
implied is made by the U.S. Geological Survey as to the accuracy
of the data and related materials. The act of distribution shall not
constitute any such warranty, and no responsibility is assumed by
the U.S. Geological Survey in the use of this data, software, or
related materials.
Any use of trade, product, or firm names is for descriptive
purposes only and does not imply endorsement by the U.S.
Government.
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None. This dataset is provided by USGS as a public service.
20041108
U.S. Geological Survey
Ask USGS -- Water Webserver Team
mailing
445 National Center
Reston
VA
20192
1-888-275-8747 (1-888-ASK-USGS)
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FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998