The attraction of New Caledonia, for me and especially for my biologist friend Phil Gleeson, is its vast and bizarre array of endemic plants -- species of plants that are found nowhere else. So I treasure the irony that it's here, for the first time, that I really started to look at one of the most widespread plants on the planet.
Bracken fern (Pteridium) is cosmopolitan in the beautiful scientific sense of that word: it's found on every continent except Antarctica, in a vast range of climates and situations. (Cosmopolitan is more or less the opposite of endemic, which means found only in one place. Endemism -- lots of plants you won't see anywhere else -- is what biologists like Phil and dilettantish plant-lovers like me go to New Caledonia for.)
For a while, all Pteridium were thought to be a single species, which would have made it by far the world's most widespread plant. So it's not surprising that in its very ordinariness, it stands out from New Caledonia's crowd of unique personalities.
I noticed it because of how it dies.
In New Caledonia at least, dying bracken (in the sense of dying back to the surface, which is a normal part of life for this perennial fern) goes through four very distinct phases. First it's green, then it turns black, then light brown, and finally a silvery white.
At the end of this process, the shriveled plant is oddly evocative of a cow skull.
Why is New Caledonia's dead bracken white, almost silver? A Wikipedia photo from the Maritime provinces of Canada supports my faint recollection that in the Northern Hemisphere, dying bracken is mostly brown. (Is that true where you are? Go have a look; there's probably some bracken near your house. And is it only New Caledonia's bracken that goes through four color phases in the course of dying?)
To aggravate my scientist friend Phil, I might speculate that dead bracken is so intensely white here because brown wouldn't look so good against the red-brown soil that dominates this part of New Caledonia; in, short, if one could believe in intelligent design, we could praise the designer's good eye for contrasts in color.
For that matter, why is nature beautiful at all? When in our evolutionary history did one of us discover that the world is beautiful, and why did that confer an advantage on the bottom line of survival and reproduction?