Officials in at least 27 states are urging residents to report any unsolicited packages of seeds that appear to have been sent from China, warning that they might be invasive or otherwise harmful.
The agriculture departments in those states have issued statements in recent days, noting that residents had reported receiving packages of seeds in the mail that they had not ordered. Based on photos, the seeds appear to have been mailed in white pouches displaying Chinese lettering and the words “China Post,” though photos released by the Ohio Department of Agriculture show that seeds have also been sent in yellow envelopes.
Some of the packages were labeled to say they contained jewelry, according to the Kansas Department of Agriculture. The Louisiana Department of Agriculture and Forestry reported that some of the packages were labeled to say they contained earbuds or toys.
Public notices about unsolicited shipments of seeds from China were also issued by agriculture officials in Washington State, Virginia, Kentucky, Colorado, Delaware, Georgia, Iowa, Maryland, Minnesota, Mississippi, Wyoming, Montana, Nebraska, Nevada, New Hampshire, North Carolina, South Carolina, North Dakota, Oklahoma, Tennessee, Texas, West Virginia, Florida, and Alabama.
Packages of seeds have also been sent to residents in Utah and Arizona, according to local news reports. The agriculture departments in at least four other states — Arkansas, Michigan, New Jersey and Oregon — issued warnings but did not say whether any of their residents had reported receiving seeds in the mail.
Officials warned people not to plant the seeds. It was not immediately clear what types of seeds they were, but Mike Strain, the Louisiana agriculture and forestry commissioner, said in an interview that it appeared that waterlily seeds were among those received by residents of his state.
The police in Whitehouse, Ohio, where a resident reported receiving seeds, said the packages appeared to be a part of a “brushing” fraud.
“A brushing scam,” the department said on its Facebook page, “is an exploit by a vendor used to bolster product ratings and increase visibility online by shipping an inexpensive product to an unwitting receiver and then submitting positive reviews on the receiver’s behalf under the guise of a verified owner.”
Although the seeds did not appear to be “directly dangerous,” the department said, “we would still prefer that people contact us to properly dispose of the seeds.”
Kentucky’s agriculture commissioner, Ryan Quarles, asked residents to report unsolicited packages of seeds to the state’s Agriculture Department, writing on Twitter that they should “put the package and seeds in a zip lock bag and wash your hands immediately.”
Michael Wallace, a spokesman for the Virginia Department of Agriculture and Consumer Services, said on Monday that the department had received “over 900 emails and several hundred telephone calls” from people who said they had received unsolicited packages of seeds in the mail. Some of those reports came from people in other states, including Maryland, Texas and Florida, he said.
“It’s a widespread issue,” he said.
Mr. Strain, the Louisiana agriculture and forestry commissioner, said on Monday that his department had received more than 150 phone calls from people reporting unsolicited shipments of seeds, including some that appeared to have been sent from Uzbekistan. The department had confirmed that about 100 packages of seeds had been sent to residents across the state, he said.
“We are picking packages up,” he said. “We’re sending our field personnel as soon as a call comes up.” The department had heard from some residents who said they had planted the seeds. The department, he added, planned “to destroy whatever is planted.”
The Florida Department of Agriculture and Consumer Services said in a statement on Monday that about 160 people had reported receiving seeds in the mail.
The U.S. Agriculture Department’s Animal and Plant Health Inspection Service has been notified about the seed packages, said Cecilia Sequeira, a spokeswoman for the service. The agency was working with U.S. Customs and Border Protection and state agriculture departments “to prevent the unlawful entry of prohibited seeds and protect U.S. agriculture from invasive pests and noxious weeds,” Ms. Sequeira said.
“Please hold onto the seeds and packaging, including the mailing label, until someone from your state department of agriculture or A.P.H.I.S. contacts you with further instructions,” Ms. Sequeira said. “Do not plant seeds from unknown origins.”
The Chinese Embassy in Washington did not respond to a request for comment.
Carolee Bull, a professor who leads the Department of Plant Pathology and Environmental Microbiology at Penn State University, said that planting unidentified seeds could be harmful.
“The reason that people are concerned is — especially if the seed is the seed of a similar crop that is grown for income and food, or food for animals — that there may be plant pathogens or insects that are harbored in the seed,” she said.
Seed introduction is tightly regulated in the United States, Professor Bull said. The Plant Protection and Quarantine program, which is operated by the Agriculture Department’s Animal and Plant Health Inspection Service, has strict rules for the importation of plants and seeds.
“Say that when I import seed into the country that has not been here before — wheat seed, for example — I know they’ll bring it in and they’ll actually grow it out at the A.P.H.I.S. facility to check it for disease,” Professor Bull said.