Then, an email from Guinness landed in Mr. Craig-Brown’s inbox last week. A slice of the growth had been submitted for DNA testing, and the results confirmed the doubters’ suspicions:
Doug was not a potato at all.
“Sadly the specimen is not a potato and is, in fact, the tuber of a type of gourd,” a spokesman for the organization wrote, adding, “For this reason we do unfortunately have to disqualify the application.”
To those without green thumbs, “tuber of a type of gourd” might be frustratingly oblique wording. A tuber can be any kind of swollen underground stem — including a potato. Gourds, which include pumpkins, marrows and cucumbers, are entirely unrelated plants.
So what is Doug really, where did it come from, and why did it show up in the garden near Hamilton, a city in New Zealand’s North Island? No clear answers have emerged.
Chris Claridge, a horticulturist and the chief executive of the industry group Potatoes New Zealand, which assisted in the DNA testing, described the growth as a kind of scar tissue on a wound, similar to the lumps sometimes seen on trees after a branch is removed.
“It could have had an infection, it could have had a disease, it could have just formed and grown as an accident of nature,” he said. “But it’s not even the same family as the potato.”
He added: “Put it this way: We’re good at growing potatoes in New Zealand, but we’re not that good.”
For Mr. Craig-Brown, the result was disappointing. It was also a puzzle that kept him awake at night.
