Wednesday, January 14, 2015


This word is new to me, and I’m delighted to have discovered it.
I have felt, for a long time, that we Australians badly need a word to balance “sclerophyll”
I think most of you would know that sclerophyll means “hard leaf”, and is used to describe many of our familiar native trees and shrubs. Gumtrees, wattles, banksias, grevilleas, she-oaks, melaleucas, and heath plants all have sclerophyll leaves. The leaf-type is so common in Australia that it is used to describe whole ecosystems, as well as individual plants.
But what of the rest? The ones with not-sclerophyll leaves. Ordinary leaves.
We could use a good umbrella term for them, too.

Grey Birds Eye

They are sometimes grouped together as “rainforest” plants.
This is a rather unsatisfactory term, especially to the newcomer to the field of Australian plants, who, unsurprisingly, imagines that rainforest plants must be “plants that grow in rainforests”. A little further investigation reveals that botanists’ and ecologists’ definitions of  rainforests include “dry"rainforests” - a term that is often met with derision.
Dry rain???

Crows Apple
Owenia venosa
A plant of "dry" rainforests.

Then we find that our dry scrubs, or semi-evergreen vine thickets are also classified as a type of rainforest. Fair enough, in one sense, as their plants clearly belong in the same group as those of rainforests and dry rainforests. But it makes us feel uncomfortable. Not only is there not much rain on these scrubs, but it’s really stretching a point to call them forests.

 Gumby Gumby, Pittosporum angusti-folium
A typical "dry scrub" or vine thicket plant.

And as we head further inland, there are wilgas, and a whole host of other non-sclerophyll plants which often thrive in quite open and very dry country, yet they too belong to this "rainforest" group.

Nobody, on seeing an emu apple Owenia acidula growing on a desert sandhill thinks of rainforests.

 Emu Apple, Owenia venosa, on sandhill west of Windorah.

I suspect that the absence of a satisfactory, popular, group word to describe our inland non-sclerophyll flora is part of the reason that Australians have largely ignored these highly practical species when it comes to garden and civic planting.
This is a pity, because these “ordinary leafed” plants from dry environments can be so useful in horticulture.  Drought hardy and usually frost hardy, they tend to have fast-growing deep roots (making them suitable for use near buildings), to be not very large at maturity (making them suitable for suburban gardens and street trees), and are green and shady. They deserve to be much more widely known and used.

 White Beetroot Tree
Elatto-stachys xylocarpa

Yet it's not surprising that they are generally passed over by people who want to grow something green and shady, yet reliably hardy. a suggestion that they should grow a tree of "rainforest" type is most likely to conjure up a picture of a water-hungry giant with shallow, structure-destroying roots. It’s hardly surprising that they look instead to introduced species.

So I’m drawn to the word “orthophyll”, a word which means “ordinary leaf”. It is defined on one internet glossary as “vegetation with leaves mostly of ordinary texture, as opposed to sclerophyll”.
The word seems to have been invented around 1970 by an American botanist (Francis Raymond Fosberg) who needed a useful term for his work on island ecologies. It is used worldwide to include plants such as maples, ashes, and willows as well as non-deciduous plants with “ordinary” leaves. International writers also use it to describe the relevant Australian plants.

White Bollygum
Neolitsea dealbata.
An Australian orthophyll tree.

Some Australian botanists have also used it. Apparently like me, they have thought it seems like a more acceptable term for the group, than “rainforest”. On the whole, though, our botanists don’t seem to be drawn to it.
Perhaps it’s because it’s a little difficult to define “ordinary” with any real precision?
That's the virtue of the word, though. The concept of an ordinary leaf is quite elastic enough to allow for all the variations of texture that can be found in non-sclerophyll leaves.
Orthophyll. I like it.

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