In what may be the closing chapter of the mystery seed saga, Amazon (AMZN  ) is banning the sale of foreign plant species on its flagship platform. Seeds of mysterious origin, often postmarked from China, were mailed to countless customers around the globe in a curious story that leaves more questions than answers.

The Wall Street Journal first reported on the ban on Saturday, reporting on an email that Amazon sent to foreign sellers. According to the email, sellers would be totally banned from selling seed or plant products on the company's platform, effective September 3. Amazon removed postings on its platform and updated its rules for sellers to this end. Amazon has not responded to any inquiries for comments by the press as of the writing of this article.

Amazon did, however, release a statement in the email, saying, "Moving forward, we are only permitting the sale of seeds by sellers who are based in the U.S."

Any sellers who violate Amazon's new rules will be permanently banned from the platform, an unsurprising move given the reputation hit that Amazon took amid the strange fiasco.

The saga of Amazon's mystery seeds began when consumers began receiving packages of mysterious seeds that they had not ordered. The seeds were often postmarked from China, and at first were unidentified. Over time, however, the seeds were eventually identified to be from a variety of species, including lavender and roses.

Inspections of the seeds by the USDA found that some of the seeds had issues, including viruses and pests that could be devastating if introduced into the ecosystem. The USDA has advised that recipients of the mystery seeds avoid planting them.

It has been months since the seeds began to arrive on the doorsteps of consumers around the world, and there is still no definitive explanation for the mysterious seeds. The most commonly accepted answer is that it is a "brushing scam."

"At this time, we don't have any evidence indicating this is something other than a 'brushing scam' where people receive unsolicited items from a seller who then posts false customer reviews to boost sales," said the USDA.