Missouri agricultural officials are warning residents about an over-the-phone chemical sales scam offering a high-quality herbicide below store prices.

The state Department of Agriculture says the new scam involves a telephone solicitor who has been calling farmers, gardeners and homeowners across the state. The solicitor tries to sell the herbicide, which is billed as comparable to name-brand products.

The department suggests residents ask any person selling agricultural chemicals for a copy of the product label. Properly labeled products will be marked with an EPA registration number, list of active ingredients, number of feet or acres the product will cover and other information.

The department offers an online database in which consumers can search for products by company name, product name or EPA identification number.