How Many Local Native Plants Are There?

When I first proposed putting out a book on local native species, one of my friends was embarrassed for me. I asked him to guess how many there were, and he thought there might be fifteen. So the Chronicle’s estimate (above) is a generous one by comparison.
When I put out my book “Toowoomba Plants”, I included in it 274 trees and shrubs, and 19 mistletoes. These were all plants growing naturally on the basalt soils (red and black soils) of an area roughly bounded by the border between Queensland and New South Wales, the great Dividing Range, the Bunya Mountains and the Condamine River.
It is not the full range. Because the topic of the book was “natives of the region suitable for gardens”. I left out plants with names like “blind-your-eye” and “giant stinging tree”, any whose fruits were known to have poisoned children, and any others which I just didn’t like the look of. There are also quite a few desirable plants which I missed, simply because I didn’t know about them at the time.
My second work-in-(rather slow) progress is intended to be an “everything else” book - limited only by the suitability and desirability of the plants for garden use. I am having a problem, however. There are just so many vines, flowering annuals and perennials, orchids, lilies, bulbs, ornamental grasses, rushes, sedges, reeds, saltbushes, and water plants, native to this area, that I can’t possibly put them all into one book. I’ll need to be rather ruthless and select only the ones which I think are the best...
So how many local native plants are there overall? Well I’m not going to get into counting them, but my guess is that something like 3,000 of Australia’s estimated 25,000 native plants occur naturally here. The same situation would apply almost anywhere in the country. Some areas are richer, of course, and arid areas are poorer, but on the whole, no matter where we are in Australia, it would be possible to make an interesting and diverse garden using only local natives.
I think the difficulty that Australians have in accepting that our own flora is so rich and diverse is a leftover from the attitudes that came with our earliest white settlers from Britain, and has never been completely laid to rest.
The British flora was largely wiped out during the ice ages. When the climate began to warm up, plants began to creep back in from the south. As global warming, meanwhile melted the ice, and sea levels rose, and when the English Channel filled and cut Britain off from Europe, (about 10,000 years ago), there was a native flora of around 270 species - about the same as modern Scandinavia. Since then, with seed that has blown in or drifted across, the number of plants generally agreed to be native to Britain - those not introduced by humans - has increased to about 1500.
Of these, only 36 are trees, and there are a further 8 large shrubs.
For the British, by the time Australia they sent their first emigrants to Australia, it was taken for granted that the only way to have interesting diversity in their gardens was to fill them with imports.
We have inherited this attitude, and non-native plants are still being imported into our country at a great rate, often to fill garden niches which could have been better filled by a native - had our gardeners only taken enough interest in the natives to find out what they were. It is now estimated that we have introduced 27,000 plant species to Australia in the last 222 years - more than all our native flora put together!