... Inco grows 50,000 subterranean seedlings a season of red pine and jack pine more than a kilometre down (a) 2.3-kilometre mine shaft that is set to plunge further in the next decade to reach more nickel, copper and platinum-group metals. The tree nursery is located at a higher level that has already been depleted of its resources and is no longer in use yet is still easily accessible via mine hoist.
... Growing underground seems completely counter to the concept of, well, garden-variety horticulture that normally occurs out in the open air under just the skies and some much-needed rainfall. But it turns out that a steamy mine is a perfect environment for tree growing. For starters there's a constant humidity and geothermal heat of 25C year-round.
"The underground nursery works because there is an ambient rock temperature, it's warm and you don't have to heat a greenhouse in cold weather in Sudbury.”
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