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Bracken



At 10:23 PM 08/06/2000 -0400, John Bois wrote:
It's not obvious to me what role bracken plays/played now or then.  Stan,
could you spell it out a bit more.  i thought this plant was limited in
its range--although I've heard of desert bracken.

Bracken is practically worldwide in distribution, and can certainly form dense and extensive thickets. However, according to Stewart's "Paleobotany and the Origin of Plants" (I only have the first edition, so this may be out of date) the genus Pteridium, to which bracken belongs, is only known from the Tertiary, though some Jurassic and Cretaceous fossils may be assignable to the large and varied family Polypodiaceae to which it belongs.


That is not to say,of course, that ecological equivalents may not have existed in the Mesozoic - given the absence of grasses I wouold be amazed if there were no such plants. And of course bracken is not the only living fern capable of providing concealment; Dicranopteris ferns form high, dense and pretty much impenetrable thickets along forest edge in many tropical areas, including Hawaii.

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