Thursday, May 29, 2008

Resurrection Ferns

The Only Truly Drought-hardy Ferns
Cheilanthes species
Family: ADIANTACEAE
We are accustomed, in this district of drought-hardy plants, to those which look dead in dry times then revive when it rains. Some do it by letting their leaves die, and re-shooting from the stems. With others, it seems to be the whole plant that dies, but under the ground the roots, or perhaps the tubers, hibernate waiting for rain to wake them up. Still others put all their drought-hardiness into their seeds which will can remain viable, in some species, for hundreds of years.
This fern, however, has an amazing trick. Those very leaves which seemed quite dead - they were brown, dry, and crisp on their stems - can soak up a shower of rain and become soft and green again. Plants which were looking miserable only yesterday may be looking as good as new tomorrow, with this little bit of rain we've had.
Resurrection ferns are hardy in other ways as well. They cope happily with full sun or shade, survive frosts, re-grow from their roots after bushfires, and grow naturally in both acid and alkaline soils. Their only dislike is having their roots disturbed.
There are three local species.
The “mulga fern”, Cheilanthes sieberi, shown in the photograph above, is the tallest of them at 25cm. It differs from the others in being hairless, and in being the easiest to grow.
“Bristly cloak fern”, C. distans, has shiny black stems like those of the mulga fern, but the leaves are hairy on the undersides. It only reaches a height of 20cm, and may be the frost hardiest of the three. Unfortunately it can be difficult to grow and is very difficult to transplant successfully.
The “Woolly cloak fern” at left, (C. lasiophylla) is hairer still. Both the leaves and the stems are hairy, with the unfurled fronds, as you can see, looking, as the name suggests, rather white and woolly. It is the smallest of the set at 15cm.
All three are plants which, once established, are well worth having. Because of the difficulty in transplanting them, they should be valued where they occur naturally.

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