A mass of quinoa seeds excavated from an archeological dig at a Brantford, Ont., construction site has been identified as being 3,000 years old, raising questions about the extent of trade among Indigenous peoples at the time.

The 140,000 seeds, which originate from the Kentucky-Tennessee area, seem as if they were "processed for delivery," said Prof. Gary Crawford of the department of anthropology at the University of Toronto.

The findings were published in the December 2018 issue of American Antiquity.

"This is just one of these unbelievably fortuitous discoveries," said Crawford.

"It just shows us that sometimes what seems to be a relatively insignificant site can have something incredibly important on it."

Crawford says no one has reported this type of quinoa in Ontario before, and the discovery leads to more questions than answers, especially when it comes to trade.

Sometimes what seems to be a relatively insignificant site can have something incredibly important on it. - Gary Crawford, University of Toronto

He says the discovery shows that crops were part of trade at the time, and suggests that people in what is now Ontario were connected to others farther south.

He says it's possible the seeds were grown here, but there's no evidence.

"Of course the lack of evidence doesn't mean they weren't growing it. But for now I think the safe interpretation is this stuff was being imported," said Crawford.

The seeds were found in 2010, after the site was assessed to see if there were any relevant archeological items in the area. Crawford says there was nothing unusual about the initial findings, as most of the items came from the area.

It wasn't until the team examined sediment from a pit beside the site that they discovered something much bigger.

"It's the first time I've been close to being shocked in 45 years of research, and I would say more delighted and surprised than shocked, but it was one of those 'O-M-G' moments that one gets when they're doing research," said Crawford.

"Indigenous Canadians and Native Americans are and were sophisticated people, as sophisticated as anyone else in the world, and they were involved in fascinating kinds of things," said Crawford.

Paula Whitlow, museum director at Woodland Cultural Centre in Brantford, says it isn't really understood how Indigenous people traded back then. But it is understood there was an "extensive trade network."

Whitlow notes that the largely peaceful Indigenous people who occupied the area at the time had an extensive trade network and even a city, Onondaga, that covered some 15 acres.

The next step with the seeds, Crawford says, is to look at "relatives" of this type of quinoa in the Ontario area.

"I think we need to work together with botanists to sort out whether the wild species that grows in Ontario is actually a feral version of this crop and whether weed distributions we see in the province today actually can be traced way back to Indigenous Canadian activity in the province," said Crawford.