Stefan A. Voss Wesley R. Henson 20260327 tabular digital data https://www.sciencebase.gov U.S. Geological Survey U.S. Geological Survey Data Release https://doi.org/10.5066/P13GVUVQ Agricultural land use estimates are vital to understanding agricultural production, economic contributions, and water demands. A method to estimate spatially and temporally distributed agricultural land use was developed for California. Pesticide application records were processed to develop annual statewide estimates of agricultural land use at approximately 1-square mile resolution. Evaluation of method performance included statewide analysis and enhanced analysis of an agriculturally diverse 5-county subarea. Results were compared to two independent reference datasets: (1) maps of remotely sensed agricultural land use and (2) agricultural economic reports. Results show reasonable correspondence with the reference data sets as evaluated by linear regression, percent average estimation error (PAEE), and spatial analysis (r2 = [0.28 - 0.80], PAEE = [1.7% - 22.7%]). This novel method provides independent evaluation and validation of, and reduces uncertainty in, estimates of current and historical land use. Land use area estimation methods involve inherent uncertainty. The California Pesticide Use Reporting Land Use Estimation (CalPUR-LUE) method (Henson and others, 2023) provides an independent dataset that can support evaluation and validation of remotely sensed data and reduce uncertainty in estimates of cropped land use. The data provided in this data release summarize cropped land use estimates across California, with enhanced analysis additionally drawing from county economic reports in Kings, Monterey, San Joaquin, San Luis Obispo, and Santa Cruz counties in California in 2018. 20180101 20181231 ground condition Complete None planned -124.3753 -114.1325 42.0018 32.5405 ISO 19115 Topic Category farming geoscientificInformation location imageryBaseMapsEarthCover society None Pesticide use USGS Thesaurus water use land use and land cover land use change agriculture pesticide and herbicide contamination USGS Metadata Identifier USGS:65cba7f5d34ef4b119cb3759 Common geographic areas California Kings Monterey San Joaquin San Luis Obispo Santa Cruz None. Please see 'Distribution Information' section for details. These data are marked with a Creative Common CC0 1.0 Universal License. These data are in the public domain and do not have any use constraints. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. It is requested that the suggested citation for this USGS data release be included in any publications that reference or utilize these data. Stefan Voss USGS - SOUTHWEST REGION Hydrologist mailing and physical

California Water Science Center, California District Office - Placer Hall

Sacramento CA 95819 916-278-3000 savoss@usgs.gov Muffet Wilkerson, California Department of Water Resources (DWR) retired; Andres Guillen, DWR; Lan Liang, Paul Shipman, DWR; DWR; Jing Yuan, DWR; Stanley Mubako, DWR; Steve Ewert, DWR; Deidre Herbert; Matt Baillie; Jake Hesslau; Anav Mittal. Microsoft Windows 10+, , Microsoft Excel for Microsoft 365 MSO (Version 2506), Python 3.9.2 Wesley Henson Deidre M Herbert Stefan Voss 20231122 application/service https://code.usgs.gov U.S. Geological Survey U.S. Geological Survey software release https://doi.org/10.5066/p9guwkzz Modeled output data were evaluated in comparison to reference dataset by ordinary least squares regression analysis, Mann-Whitney test, and percent average estimation error. Modeled output data were checked for falling within reasonable acreage ranges by outlier analysis. Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Additional sample data may be added to this data release in the future. Horizontal accuracy was not assessed for this dataset. Vertical accuracy was not assessed for this dataset. California Department of Water Resources 20210319 vector digital data Abbreviated as "DWR" https://data.cnra.ca.gov/dataset/statewide-crop-mapping/resource/2dde4303-5c83-4980-a1af-4f321abefe95 Digital and/or Hardcopy 20180101 20181231 observed Department of Water Resources, 2018 Comparison data set California Department of Food and Agriculture 2019 publication Referred to as "county commissioner crop reports" https://www.cdfa.ca.gov/exec/county/CountyCropReports.html Digital and/or Hardcopy 20180101 20181231 observed California Department of Food and Agriculture, 2018 Comparison data set California Department of Pesticide Regulation 20220617 tabular digital data Abbreviated as "CalPUR" https://files.cdpr.ca.gov/pub/outgoing/pur_archives/ Digital and/or Hardcopy 20180101 20181231 publication date California Department of Pesticide Regulation, 2018 Base data set for analysis (1) Pesticide application data from 2018 were downloaded from the CalPUR database as text files. (2) The data were aggregated to spatial unit (county, section, detailed analysis unit [DAU]) by crop class. The CalPUR database has over 500 defined crop types and land uses, and in order to uniformize the data with the comparison data sets, each crop class in the CalPUR database was classified into a crop group. For example, Iceberg, Bibb, Boston and Romaine lettuce crops were aggregated into a single “lettuce” crop group matching agricultural reporting and remote sensed data categories. Crop groups were then associated to California Department of Water Resources (DWR) crop classes. (3) Crop data was categorized into annual cropped or multicropped. Crop groups which are planted on the same fields for the entire year (e.g., artichokes) were classified as annual cropped whereas those with shorter growth cycles that may result in the same field being planted with multiple plantings throughout the year (e.g., soybeans) were classified as multicropped. (4) Annual cropped and multicropped acreage totals were aggregated to the annual timescale at each spatial unit. Although the acreage totals could be generated on a month-to-month basis, aggregation at the annual timescale was selected because multicropping can confound estimation and because pesticides are not necessarily applied to every field in every month of the growing season. (5) Each record of application in each section was filtered by unique grower identifier, site location identifier, and crop class to prevent inclusion of duplicate records. (6) After filtering, annual aggregated acreage estimates were produced at the section and county scales for each crop group. California Department of Pesticide Regulation, 2018 Department of Water Resources, 2018 20230701 The software outputs a series of tables as csv files containing the full parsed data set from the CalPUR database, the data set after duplicate entries have been removed, the data set after filtering by grower ID and site location, and the estimated acreage sums at the county and section scales. California Department of Pesticide Regulation, 2018 20230701 The acreage estimate results are compiled into tables with DWR remote sensed estimates and county commissioner crop report estimates, and separate tables compiling Mann-Whitney test results and ordinary least squares regression coefficients are also produced. Department of Water Resources, 2018 California Department of Food and Agriculture, 2018 20230701 Finally, scatter plots comparing CalPUR-LUE and DWR are produced, as well as spatial plots and bar plots showing CalPUR-LUE estimates, DWR estimates, and county crop report estimates. This data release comprises only the tabular data output, the figures are not included. California Department of Pesticide Regulation, 2018 Department of Water Resources, 2018 California Department of Food and Agriculture, 2018 20230701 Mercator_1SP 0.0 0.0 0.0 0.0 0.0 0.0 coordinate pair 0.6096 0.6096 meters WGS_1984 WGS 84 6378137.0 298.257223563 DWR_COMTRS_Table.csv Comma Separated Value (CSV) file containing DWR produced acreage data by crop ID at the COMTRS scale. Producer Defined COMTRS County-meridian-township-range-section (COMTRS) location associated with acreage estimate. Producer Defined Public Land Survey System (PLSS) designation of county, meridian, township, range and section (COMTRS). E.g. 01M05S04E22 01-county code for Alameda county. M – 1st Principal Meridian: The reference meridian used to define the east-west range lines. 05S – Township 5 South: The location is 5 townships (each 6 miles) south of the baseline. 04E – Range 4 East: The location is 4 ranges (each 6 miles) east of the principal meridian. 22 – Section 22: A 1-mile by 1-mile square within the township, numbered 22 out of 36. DWR_CROP_CLASS Categorical identifier designating crop class associated with acreage estimate. Producer Defined T Vegetable Producer defined D Deciduous Producer defined F Field Producer defined G Grain Producer defined P Pasture Producer defined V Vineyard Producer defined C Citrus Producer defined R Rice Producer defined DWR_ACRES Remotely sensed acreage estimate for the specified crop class in the specified section. Producer Defined 0 1645.32 acres COMTRS_Table.csv Comma Separated Value (CSV) file containing CALPUR-LUE produced acreage data by crop ID at the COMTRS scale. Producer Defined COMTRS County-meridian-township-range-section (COMTRS) location associated with acreage estimate. Producer Defined Public Land Survey System (PLSS) designation of county, meridian, township, range and section (COMTRS). COUNTY_CODE County code designation for the acreage estimate. Producer Defined '01' Alameda County Producer defined '02' Alpine County Producer defined '03' Amador County Producer defined '04' Butte County Producer defined '05' Calaveras County Producer defined '06' Colusa County Producer defined '07' Contra Costa County Producer defined '08' Del Norte County Producer defined '09' El Dorado County Producer defined '10' Fresno County Producer defined '11' Glenn County Producer defined '12' Humboldt County Producer defined '13' Imperial County Producer defined '14' Inyo County Producer defined '15' Kern County Producer defined '16' Kings County Producer defined '17' Lake County Producer defined '18' Lassen County Producer defined '19' Los Angeles County Producer defined '20' Madera County Producer defined '21' Marin County Producer defined '22' Mariposa County Producer defined '23' Mendocino County Producer defined '24' Merced County Producer defined '25' Modoc County Producer defined '26' Mono County Producer defined '27' Monterey County Producer defined '28' Napa County Producer defined '29' Nevada County Producer defined '30' Orange County Producer defined '31' Placer County Producer defined '32' Plumas County Producer defined '33' Riverside County Producer defined '34' Sacramento County Producer defined '35' San Benito County Producer defined '36' San Bernardino County Producer defined '37' San Diego County Producer defined '38' San Francisco County Producer defined '39' San Joaquin County Producer defined '40' San Luis Obispo County Producer defined '41' San Mateo County Producer defined '42' Santa Barbara County Producer defined '43' Santa Clara County Producer defined '44' Santa Cruz County Producer defined '45' Shasta County Producer defined '46' Sierra County Producer defined '47' Siskiyou County Producer defined '48' Solano County Producer defined '49' Sonoma County Producer defined '50' Stanislaus County Producer defined '51' Sutter County Producer defined '52' Tehama County Producer defined '53' Trinity County Producer defined '54' Tulare County Producer defined '55' Tuolumne County Producer defined '56' Ventura County Producer defined '57' Yolo County Producer defined '58' Yuba County Producer defined DWR_CROP_CLASS Categorical identifier designating crop class associated with acreage estimate. Producer Defined C Citrus Producer defined D Deciduous Producer defined F Field Producer defined G Grain Producer defined P Pasture Producer defined T Vegetable Producer defined V Vineyard Producer defined R Rice Producer defined MTRS_AREA_ACRES Total acreage of the section as determined by PLSS. Producer Defined 103.05 1440.7 acres CALPUR_ACRES CalPUR-LUE estimate of acreage of the specified crop class in the specified section. Producer Defined 0 4004.7 acres County_Table.csv Comma Separated Value (CSV) file containing acreage data produced by DWR and CALPUR-LUE at the county scale; and county crop report data in the enhanced analysis sub-area. Producer Defined COUNTY_CODE County code designation for the acreage estimate. Producer Defined '01' Alameda County Producer defined '02' Alpine County Producer defined '03' Amador County Producer defined '04' Butte County Producer defined '05' Calaveras County Producer defined '06' Colusa County Producer defined '07' Contra Costa County Producer defined '08' Del Norte County Producer defined '09' El Dorado County Producer defined '10' Fresno County Producer defined '11' Glenn County Producer defined '12' Humboldt County Producer defined '13' Imperial County Producer defined '14' Inyo County Producer defined '15' Kern County Producer defined '16' Kings County Producer defined '17' Lake County Producer defined '18' Lassen County Producer defined '19' Los Angeles County Producer defined '20' Madera County Producer defined '21' Marin County Producer defined '22' Mariposa County Producer defined '23' Mendocino County Producer defined '24' Merced County Producer defined '25' Modoc County Producer defined '26' Mono County Producer defined '27' Monterey County Producer defined '28' Napa County Producer defined '29' Nevada County Producer defined '30' Orange County Producer defined '31' Placer County Producer defined '32' Plumas County Producer defined '33' Riverside County Producer defined '34' Sacramento County Producer defined '35' San Benito County Producer defined '36' San Bernardino County Producer defined '37' San Diego County Producer defined '38' San Francisco County Producer defined '39' San Joaquin County Producer defined '40' San Luis Obispo County Producer defined '41' San Mateo County Producer defined '42' Santa Barbara County Producer defined '43' Santa Clara County Producer defined '44' Santa Cruz County Producer defined '45' Shasta County Producer defined '46' Sierra County Producer defined '47' Siskiyou County Producer defined '48' Solano County Producer defined '49' Sonoma County Producer defined '50' Stanislaus County Producer defined '51' Sutter County Producer defined '52' Tehama County Producer defined '53' Trinity County Producer defined '54' Tulare County Producer defined '55' Tuolumne County Producer defined '56' Ventura County Producer defined '57' Yolo County Producer defined '58' Yuba County Producer defined DWR_CROP_CLASS Categorical identifier designating crop class associated with acreage estimate. Producer Defined T Vegetable Producer defined D Deciduous Producer defined F Field Producer defined G Grain Producer defined P Pasture Producer defined V Vineyard Producer defined C Citrus Producer defined R Rice Producer defined DWR_ACRES Remotely sensed acreage estimate for the specified crop class in the specified county. Producer Defined 0 425158 acres CROP_REPORT_ACRES Acreage estimate of the specified crop class in the specified county from the county commissioner agricultural report. Producer Defined 0 364629 acres CALPUR_ACRES CalPUR-LUE estimate of acreage of the specified crop class in the specified county. Producer Defined 0 418833 acres This data release contains tabular data in three .csv files: DWR_COMTRS_Table.csv, COMTRS_Table.csv, and County_Table.csv. These files comprise acreage and crop type data at the county-meridian-township-range-section (COMTRS) and at the county scales. The data produced by the California Pesticide Use Reporting Land Use Estimation tool (Henson and others, 2023) are presented alongside two reference datasets: one statewide dataset produced by the California Department of Water Resources (DWR) and one 5-county sub-area dataset produced from county economic reports. Stefan A. Voss, and Wesley R. Henson, 2025, California Agricultural Land Use Estimates Derived from Pesticide Use Reporting Data, https://doi.org/10.5066/P13GVUVQ. Henson, W.R., Herbert, D.M., Voss, S.A., 2023, CalPur Land Use Estimation Processing Script, version 1.0, U.S. Geological Survey Software Release, https://doi.org/10.5066/P9GUWKZZ GS ScienceBase U.S. Geological Survey mailing address

Denver Federal Center, Building 810, Mail Stop 302

Denver CO 80225 United States 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Digital Data https://doi.org/10.5066/P13GVUVQ None 20260327 Stefan Voss U.S. Geological Survey, SOUTHWEST REGION Hydrologist mailing address

6000 J Street Placer Hall

Sacramento CA 95819 US 916-278-3109 savoss@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998