Ah Snopes. but these some vegetation included barley.
"The Greenland climate was mild when they landed, but was it warm enough for growing corn?
Researchers from the National Museum in Copenhagen say the answer to the question is ‘yes’. In a unique find, they uncovered very small pieces of charred grains of barley in a Viking rubbish heap on Greenland.
The find is final proof that the first Vikings to live in Greenland did grow barley – the most important ingredient in brewing beer, making a form of porridge or baking bread, traditionally seen as staple foods in the Vikings’ nutritional diet."
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"Wild barley is not strong enough to grow in Greenland, says Henriksen, who also rules out imported barley, as even small quantities of grain would be too much for the cargo hold of the Vikings’ ships.
“If the corn had been imported, it would have been threshed, so finding parts of grains of barley is a very strong indication that the Vikings grew their own corn,” he adds. The find also confirms researchers’ theory that the Vikings tried to continue the form of life they knew so well from their original homes.
Little Ice Age stopped corn cultivation
The Greenland climate was a bit warmer than it is today, and the southernmost tip of the great island was luscious and green and no doubt tempted Eric the Red and his followers. This encouraged them to cultivate some of the seed corn they brought with them from Iceland.
The Vikings also tried to grow other agricultural crops. Their attempts to grow these crops and barley did not last long, however, as the climate cooled over the next couple of centuries until the Little Ice Age started in the 13th century."
https://www.sciencenordic.com/agriculture-archaeology-denmark/vikings-grew-barle...