It appears that rotenone (a powerful piscicide) is actually banned [0]. Same document also indicated that copper sulfate use is limited to specific situations/c

It appears that rotenone (a powerful piscicide) is actually banned [0]. Same document also indicated that copper sulfate use is limited to specific situations/crops. Though, of course, conventional crops also have restriction on the use of pesticides, presumably they are less restricted. [0] https://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=9874504b6f1025eb0e6b67cadf9d3b40&rgn=div6&view=text&node=7:3.1.1.9.32.7&idno=7#se7.3.205_1602 https://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=9874504b6f1... edit: This, of course, only applies to the USDA organic program. Products produced elsewhere may have different rules.