A New Way of Identifying Local Plants

It’s always been a problem.
You see a pretty tree in the local bush, or rainforest, or on your new block of land. You want to find out what it is, but nobody seems to know.
There’s a new tool that has just been released this week, that helps with a big chunk of the problem. It is an interactive identification key, on a USB, called:


It’s available from http://rainforests.net.au or http://www.rainforestpublishing.com.au , where you can also see some good illustrations showing what’s in the program.
The plants it covers are trees (including fern trees and palms), shrubs, climbers, and mistletoes. The definition of “rainforest” is very broad. All our local dry rainforest and scrub plants are in there, even those which are technically of "rainforest type", but grow in obviously non-rainforest situations out on the Downs. You’ll find wilgas, for instance.
The program costs $80.00. My first thought, being a frugal body, is that it is somewhat expensive. However, I had a second thought which is that it contains so very much more than could ever be put into in a single book that’s it’s a bargain. For instance there are over 12,000 photos!
The best thing is the key itself. My experience with conventional plant keys is that I can get lost somewhere in the pick-a-path process. This key, having the advantages of computer technology, lets you arrive at an ID from many different angles.
The keying-out process begins with the total list of plants, all 1139 of them, and every time you add a bit of information, it gets shorter, until you are left with the answer to your question.
First you put in what type of plant you have (tree, climber, palm, etc). At once, the list is shortened as other plant types are subtracted from it.
Then you might put in that your mystery plant has pink fruits. All the plants without pink fruits disappear from the list. Put in a few other characteristics that are obvious to you - maybe the geographical area, the size of the fruits, and the length of the leaves, and you may even end up with just your target plant left on the list already!
If you haven’t got there yet, there are loads of other questions you can answer to work towards an ID. At first some of these can look daunting. Is the leaf elliptic, ovate or lanceolate, for instance? What do the words mean?
No worries, clicking on a little icon next to the words brings up an illustrated description of all the leaf shapes, so you can easily find the word that best matches your plant sample.
The plant descriptions are also a help. Each plant name in the list has little icons beside it.
Clicking on them brings up a written description with photos, and a black and white sketch showing important identifying features. The pictures are a help when you have got the list of possible plants down to the last few, but can’t decide which one is your unidentified plant.
The other great thing is that there is a species index. You click on a plant name that interests you, and by the time you’ve read the description and looked at the photos of the whole plant, plus close-ups of the trunk, flowers, fruits, leaves (both sides) and so on, you really feel you know the plant.
Great stuff!

Cuttsia

Cuttsia viburnea
Family: CARPODETACEAE
Now flowering - and what attention-grabbing flowers these are!

In their typical habitat, a shady creek bed in rainforest understorey, these gleaming white flowers led my eyes to a plant I might otherwise have overlooked. The strong honey scent of their nectar-rich flowers was attracting the attention of many insects. Little quiet birds were coming as well, to feed on the insects, making the point that insect-attracting plants have value not only for the insects in their environment.
If fertilised, the flowers of this plant produce heavy seed crops in their little capsules. However,  as with many bisexual-flowered plants, Cuttsia plants are not self-fertile. Separate timing of the maturing of their flowers' male and female parts means that the flowers of isolated plants remain unfertilised, despite visits from many suitable pollinators.To produce seeds it must grow close to a friend or two.

A solitary plant makes a lovely garden specimen, but seed production matters if we are trying to re-introduce lost ecosystems or reproduce something like a natural environment in our own gardens. Don’t overlook the possibility of planting several quite close together if space is limited. This would result in something resembling a multi-stemmed large shrub or small tree.
Cuttsias grow best where there is constant soil moisture. Where this can be provided, this is an excellent plant for an understorey situation or a shady corner. Established plants do tolerate some drought, but would need to be helped along if the dry spell is prolonged.
They are claimed to be frost hardy.

There have been a few attempts to give this plant a “common” name. Some people call it elderberry (but it’s not an elderberry, and Australia has several genuine elderberry species which might even be growing side by side with this plant in the wild). Others call it native hydrangea (but it isn’t related to hydrangeas, and doesn’t resemble them much, as you can see). The name “native hydrangea” is more commonly used for the closely related Abrophyllum ornans, so like “elderberry, is not a particularly practical one. Others call it honey flower, which is very appropriate considering its strong nectar scent. Unfortunately, if you say “honey flower”, people are more likely to think you are speaking of another Australian plant, Lambertia formosa. Falling back on the botanical name, as we have done for grevilleas and quite a few other Australian plants, seems the best solution to achieving a user-friendly name for everyday use.

Bellfruit and the Fire Ecology.

Codonocarpus attenuatus
Family: GYROSTEMONACEAE 
This is a surprising plant.
Its soft leaves make it look a rainforest species, but this may not be the case.
There are records of it being found in rainforests. However if they were seen when not fruiting, it’s a fair chance that the plants were actually bellfruit’s rare and endangered relative, Gyrostemon osmus, which was generally unknown until it was studied and named in 2005. It looks very like bellfruit, but has seed capsules that open along a dorsal split, unlike bellfruit capsules which drop their seeds out of the bottom.
The remainder of bellfruits's relatives, both Codonocarpus and Gyrostemon species, are plants of the desert or dry country out west.
Bellfruit itself is “Mr In-between”. Found in coastal and sub-coastal sites, it hangs about on the edges of dry rainforests and in disturbed areas hoping for fire to help its seeds germinate.
Australian ecosystems can be broadly divided into two groups – those (like rainforests and vine thickets) which are damaged and reduced by fire, and the “fire ecologies”, which depend on fire for good health. The latter are populated by plants which thrive with regular fires, and may even depend on them for the species’ long term survival. If the rainforest specimens are all actually Gyrostemon osmus, then we can place the true bellfruit, Codonacarpus attenuatus on the "fire" side of the fence.

The plants above, which I photographed a few days ago, were in a typical site. It is a large council-owned reserve in the Merritt’s Creek Road area which was covered with fairly open vegetation until it was given a clean-up burn in 2010. The result, in a mere four years, is this extremely thick growth of wattles Acacia neriifolia (another fire-loving plant) and bellfruit (centre plant with light grey trunk). Loving the fire, they came up like hairs on a cats' back from seed lying dormant in the soil.
The scrub is now about 6m tall. Crowding has resulted in tall thin plants with bare trunks and dense leafy growth at the top only.
Not all the bellfruit trees in the scrub have seeds on them, because the species has separate male and female plants.

                                                                                                                       Photo by Dougal Johnston
There are, however, plenty of male plants to ensure fertilisation of the female plants. They were heavily laden with their little green "bells". As the species is wind-pollinated, there is always a chance that having too few plants in the area might result in uneven pollination, with pollen failing to reach all the female flowers. This is clearly not the case there!
Bellfruit trees are not often grown in gardens, largely because they are not often available for purchase. Seeds are difficult to germinate, but are known to do better if soaked in smoke water.

Gardeners would need to put in several plants, to be sure of having specimens of both sexes, if they want to get the ornamental "bells".









Specimen plants grown in the open are likely to be as little as one third the height of the plant shown at left, and to have canopy almost to the ground.





















In gardens, a useful planting style can be to put a small group of bellfruit close together. This can result in plants (of both sexes) forming a united canopy, looking rather like a multi-stemmed large shrub.

Like many other fast-growing pioneer trees, bellfruits probably have a relatively short lifespan.

Foambark Tree

Jagera pseudorhus
Family: SAPINDACEAE
These beautiful trees are showing off their seeds in the local rainforest at present.

Photo by Glenda Walter
I was sent this photo by a friend, who took it in Brisbane, but the plants can also be found locally at Goomburra, Ravensbourne, and the Bunya Mountains.
Foambark is a fast growing tree, usually reaching no more that 10m in cultivation. It has an attractive shady canopy, inconspicuous white flowers in spring, and these lovely fruits in autumn. They gleam redly as the sun catches them.
Unfortunately, the stiff little hairs on the seed capsules break off when handled, and can cause considerable skin irritation. This is something to be considered, before planting it as a garden tree. It is not suitable for a site where children might be picking up fallen capsules.
The plant’s common name comes from an Aboriginal use for it. The bark contains so much saponin that it can froth from any little injuries, in heavy rain. This means that, if thrown in water, branches and leaves de-oxygenate the water, temporarily stunning fish for easy catching.
I used to think the tree was named for the Jagera tribe of Aborigines, and thought that it was a remarkable example of white settlers honouring the original owners of the land.
Not so, however. It was named after the Dutchman who discovered the original Jagera species in Indonesia, and it is just coincidence that there is another species in the Jagera tribe's territory. Apparently Jager means Hunter, and is a relatively common Dutch surname.

Strap Water Fern

Blechnum patersonii
Family: BLECHNACEAE 
This fern often attracts attention in damp rainforests as the it tends to grow on the earthen faces of path cuttings, on the uphill side of paths in our wetter local national parks along the Great Dividing Range. It also grows beside or in streams, and would do well in red soil gardens, in positions where it can have mulch, and shade for at least half the day.

I imagine it might be a particularly suitable plant for one of those fashionable "green walls" - provided it faced south or east and was shaded from the midday summer sun. It also grows well indoors and in areas with very low light levels.
Strap water fern grows better if watered in dry periods, but, like all our hardy local ferns, it tends to be prone to pests and diseases if the dampness is overdone. In nature, it tolerates the long dry periods of our climate, and even some light frosts. It doesn’t have to be a pampered pot plant or fern-house specimen.
The fronds of this rather delightful plant seem to be suffering an identity crisis. The simple strap  is the most common shape, but a single mature plant might have some straps, and some fronds with varying numbers of lobes.
The foliage (once the new pink fronds have dulled to green), is a rich, dark green.

The fertile fronds are very narrow indeed. It is common among ferns for the fertile fronds to be longer and skinnier than infertile ones, but strap water ferns carry the contrast to an exaggerated degree.

 




Here are two infertile fronds beside two fertile ones.
















The first time I saw this plant's narrow fertile leaves, with their heavily spore-encrusted edges, I mistook them for diseased fronds! Then I examined their backs, and realised they were heavily rimmed with spores.


Grown by itself, a single plant forms a rosette.

Thorny Yellowwood

Zanthoxylum brachyacanthum
Family: RUTACEAE
What is this plant’s future?




Here’s the trunk of a young thorny yellowwood, showing what a prickly little fellow it can be. Those thorns are sharp!
Like human teenagers, it will grow out of this prickly stage.
In older trees, the thorns thicken up and lose their sharp points. You can put your hand on the trunk of a mature tree, quite comfortably, even though it is still covered with the fat old thorns.
Notice the young vine in the photo above. Perhaps this yellowwood sapling will grow into a strong tree, up to 15 metres tall in its rainforest environment...







 

 

...or perhaps its future will be like that of the plant at right.


This one’s broad thorns tell us that it is actually quite an old plant, but life in the stranglehold of its encircling vine has not been easy. It hasn’t reached the size we might expect for a plant of its age.











Here's the trunk of a large specimen.


Thorny yellowwoods are pretty plants. Grown in optimum conditions, they become attractively shaped trees with dark, dense canopies, like this one at Peacehaven Botanic Park which I photographed three years ago.
 
Thorny yellowwoods grown in gardens, where they don’t have to compete with tall trees for light, will never reach the height of their rainforest relatives. 6-8m is a more likely maximum for a garden specimen. The plants are dioecious, so the best way to grow them might be in a grove of 3-5 trees, planted close that their canopies unite into one. This would give a high likelihood of having plants of both sexes.
They contribute to the environment by hosting swallowtail butterflies, and (in the case of fertilised female trees) producing shiny black seeds in bright red follicles to attract birds.

The Peacehaven plant is female, as these flowers show.

Australia has six Zanthoxylum species, all but this one being plants of the tropics. They all have aromatic bark, leaves and seed follicles.
Spices have been produced from most of the 250 or so overseas species of Zanthoxylum. For example, Sichuan pepper, one of the ingredients of Asian five-spice powder, is produced from the red follicles of any of several Zanthoxylum species. Young leaves and shoots of other species are used as garnishes or as an ingredient in a strongly flavoured pesto-like paste. Even the bark is used in small quantities for flavouring.
I am not aware that our local species has been used for any of these purposes, but the potential may be there.

The Rutaceae Family
This family is well known for the strong smell of its members' aromatic leaves.
Some smell wonderful, and some quite appalling.
It is a Gondwanan family, only one branch of which, (the one containing citrus fruits) has spread to any extent into the Northern Hemisphere.
Knowing the family of a plant can help us to know how to manage it, as a garden plant. Australian Rutaceae would rather you didn’t fertilise them. They are well-adapted to low-nutrient soils.
To find blogs on other local Rutaceae, search for the family name in the white search box at top left.

Leichhardt’s Ironbark

Bridelia leichhardtii
Family: PHYLLANTHACEAE
It’s interesting to see this tree at work.

Plants need something or someone to distribute their seeds about for them. Without this assistance, they would have thousands of babies with nowhere to grow but under their parents.
This tree, with its red fruits, is advertising for birds to do the job.
What it wants is for them to eat its fruit, clean its seeds, and deposit them, with a little dollop of fertiliser. It produces large numbers of fruits, so there is always a good chance that some of them will be dropped in a suitable site for growing.
Birds are attracted to the colour red. These particular  fruits are slightly translucent, and glow brightly in the sunshine, no doubt looking particularly appealing to any fruit-eating bird that flies past.
When it stops at the tree, however, it soon discovers that the red fruits are not yet ripe, but that the several black fruits scattered amongst them are soft, succulent, and no doubt delicious. Having learned this, birds are likely to return to the tree again and again during its fruiting season, spreading the fruits much more widely than they might have in just a few gorging sessions.
It is usually seen as a shady small tree, but can grow to have a prominently fissured trunk of as much as a 30cm diameter. It can also be a large, multi-trunked shrub.
It likes a well-drained soil, and can usually be found growing on hillsides, in red or black soil country.