Upwind Report

Glyphosate use in Clayton County, Iowa

Estimated farm glyphosate use in Clayton County, Iowa was 246 pounds per square mile of county land in 2019, higher than 78% of US counties.

Map of Clayton County, Iowa and nearby counties, coloring each county's cropland by estimated farm glyphosate use per square mile of county land in the 2019 high estimate. Darker colors mean more use.

2019 numbers

Per square mile of county land246lbTop 22% in the US
US
652nd of 3,060
Iowa
83rd of 99
Per square mile of cropland303lb

Ranks are by use per square mile of county land, on the 2019 high estimate, among US counties with a value. Counties with the same value share a rank.

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A picture of Clayton County against the US county median, with the source, to post or send.

Since 2000

Up from 46 in 2000 to 246 in 2019. Pounds per square mile of county land, high estimate.

Every year's numbers
Glyphosate per square mile of county land by year, in pounds
YearLowHigh
20004646
20016574
20029393
20038888
20047979
20058888
2006116116
2007167172
2008172177
2009200200
2010242247
2011256256
2012261261
2013293293
2014255260
2015251255
2016269269
2017302302
2018260265
2019246246
See Clayton County on the map

About these numbers

The main number is the county's estimated farm glyphosate use for the year divided by all of its land, water left out. A county with a little farmland can use a lot per square mile of cropland and still have far less in total than a county with more farmland, so the whole-county number is the one the map colors, ranks and compares.

These are county estimates, not records. They don't show which fields were sprayed or how much any one field got.

USGS makes a low and a high estimate, which fill in use that farms didn't report in different ways.

Per square mile of cropland is the same total spread evenly over the county's cropland only, so it's higher than the whole-county number wherever only part of Clayton County, Iowa is farmland.

Numbers are in pounds per square mile. The source gives kilograms per square kilometer, and 1 kg per km² is about 5.7 pounds per square mile.

Source: Hengl & Brungard from USGS county estimates, 2000–2019 (CC BY 4.0). Land area: US Census Bureau, 2020.

This page shows estimated farm use only. It says nothing about health and is not medical advice.