Thursday, July 28, 2011

Sticky Wallaby Bush

Beyeria viscosa
FAMILY: EUPHORBIACEAE


I found this plant growing in the Jack McEwan State Forest, near Pittsworth. The soil there is our typical “hillside black” - better drained than the heavy black soil of the Darling Downs plains, and very stony.
I wondered what was “sticky” about it, as it isn’t sticky to touch - but one of my companions pressed a specimen between sheets of newspaper, and apparently it stuck quite firmly!
The plants are dioecious. Flowers on the male bushes have little yellow flowers with no petals. They are pretty little balls of yellow stamens, framed by green sepals. Flowers on the female plants are nondescript, and followed by these fruits, which, at present, are interesting but not showy. I am not familiar with this plant, but I have seen a photo of the species, taken in Western Australia, with showy plum-red fruits. I plan to keep an eye on Jack Mack’s plants, to discover whether they will change colour as they mature.
Wallaby bushes are pleasantly attractive plants with silvery leaves. They are said to make a good screen in gardens, and to benefit from pruning. To fully appreciate the species, it would be necessary to have at least one male and one female plant, so planting a row of them does seem like a good idea.

Thursday, July 21, 2011

Native Daisies in the Main Street

Senecio pinnatifolius
FAMILY: ASTERACEAE



I was very surprised to see this yellow daisy growing in Ruthven Street. A local native plant in the main street of Toowoomba is a rare sight indeed!










I wondered whether it had sneaked in by itself, or whether it had been planted by someone who could see how very well it would fit into this designed garden in front of an inner-city church.







Our native yellowtops are one of the bright notes of winter, in this district.
I do think our tree-planted main street is an improvement on the “tar and cement” we used to have, but I was reflecting on how sad and bedraggled the deciduous trees looked when I spotted the daisies.
They were like a breath of honest fresh air, “representing the season” as it really is here in Toowoomba - a pleasing contrast to the “wannabe English” look of the trees.
For more on this gardenworthy local native plant, see Sep 2008

Thursday, July 14, 2011

Myrtle Rust Reaches Toowoomba

I saw my first case of Myrtle rust this week.
I hadn’t expected to see it in the Toowoomba area until spring. Our typically cold, dry winter would slow it down, and I thought we would be able to enjoy a brief respite before it started to spread in earnest with the warmer weather and the first summer rains.



Here it is already, however, at a friend’s place at Mt Kynoch.






It is on a malabar apple Syzigium jambos, a species which is already known to be particularly susceptible to the rust. Malabar apple has been brought to Australia from south-east Asia, and is grown for its edible fruits and its creamy powder-puff flowers. Closely related to our native lillypillies, it has become an invasive weed in some areas.
Myrtle rust is still so new to Australia (it’s only been known here for 14 months, though it may have gone undetected for a year or two before that) that we don’t know, yet, to what extent our various local native plant species will be affected. Some have already proven to be very susceptible, others less so.
One thing we do know, is that the disease is so easily spread, by insects and the wind, that it is inevitable that it will find every susceptible plant in Australia no matter what we try to do to prevent it.
Myrtle rust is restricted to members of the myrtle family (Myrtaceae). They are all trees or shrubs, so a disease which affects them has the potential to have a major impact on the Australian landscape. The likelihood is that it will make mature plants look ugly, and affect seedlings badly. A worst-case scenario is that seedlings will die en masse, and extinctions of more susceptible species will result.
Plants from this family have been very popular in gardens. The rust is going to affect the decisions we make about what we plant. We will also find ourselves deciding to remove many of them, and replace them with plants from some other family.
So far, myrtle rust has been identified on 73 Queensland species. Unfortunately there are likely to be still more species affected.
Here is a site that gives advice about what to do if you find myrtle rust in your garden.
http://www.dpi.qld.gov.au/4790_20154.htm
Don’t overlook the importance of reporting affected plants to Biosecurity Queensland on 13 25 23. They can’t prevent it or cure it, but their research will be our future guide as to what Myrtaceae are really worth planting in our gardens.
To this I would add that I believe home gardeners have a responsibility not to let their plants act as carriers which might make a bridge for the fungus to reach native bushland or commercial growers whose livelihoods are under threat.
There are some plants which I think we should remove even if they are not yet infected. I leave it to you to decide which ones, but they would obviously include any Myrtaceae that we just don’t love very much, particularly those which are still small enough to remove easily. Perhaps they should include any others of species which are already known to be very susceptible. Realistically, we have to accept that these plants’ period of beauty will end shortly, and they are certainly easier to dispose of without spreading infection if it’s done before they get it. The sooner they go, the sooner we can be planting something in their place.
There are others which we should remove as soon as they show symptoms. These certainly include the very susceptible ones. No matter how hard we fight to save them, they are always going to be reinfected. We might as well bite the bullet sooner, rather than later. It will save quite a bit of effort and money which might be put into pouring poisons into the environment to no purpose.
(Note the DPI advice on how to dispose of infected plants http://www.dpi.qld.gov.au/4790_20154.htm )
Depressed?
So am I.
I try to cheer myself up with the thought that only 10% of Australian plants are in the Myrtaceae family. Those popular Grevilleas and other Proteaceae will be unaffected, and there are a great many garden-worthy plants from other families which have never even been tried in our gardens.
Meanwhile, some Myrtaceae may prove to be resistant. I find it reassuring that there are no Eucalyptus species on the list so far. I hope I am not being premature.

The Myrtle List

Which of these are growing in your garden?
Worldwide, there are 3000 species in the Myrtaceae family. Of these, more than 2200 species are native to Australia. This is almost 10% of Australian plant species - but because they are large plants, all trees or shrubs, any disease which affects them widely could have a major impact on our landscapes.
The species are grouped into approx 70 genera. I have noted here which genera have been affected by myrtle rust in Queensland, at time of writing .


Native to Queensland:
Acmena Lillypillies AFFECTED
Acmenosperma AFFECTED
Anetholia (was Backhousia)
Angophora Applegums
Archirhodomyrtus Rose Myrtle
Asteromyrtus
Austromyrtus Including Midyim BADLY AFFECTED
Backhousia Including Lemon Myrtle, Curry Myrtle...
Baeckia Twiggy bush
Barongia
Callistemon The red, pink and white bottlebrushes.
Calytrix Fringe Myrtle
Choricarpia Scrub ironwood
Corymbia Gumtrees and bloodwoods
Decaspermum Silky Myrtle AFFECTED
Eucalyptus Gumtrees, Boxes, Ironbarks, Stringybarks, etc
Eugenia Lillypilly AFFECTED
Gossia Including Python tree, Thready Barked Myrtle, 'Aurora', and 'Blushing Beauty' AFFECTED
Harmogia (Also known as Babingtonia, Baeckia...)
Homalocalyx
Homoranthus Mouse and Honey Bush
Kardomia (Also known as Babingtonia, Baeckia...)
Kunzea
Lenwebbia
Leptospermum All those lovely tea trees
Lindsayomyrtus
Lithomyrtus
Lophostemon Brush box, Swamp box,
Lysicarpus Budgeroo
Melaleuca The bottlebrush tea trees and paperbarks AFFECTED
Micromyrtus Fringed Heath Myrtle
Mitrantia
Neofabricia
Ochrosperma (Was known as Baeckia)
Osbornia
Pilidiostigma Plum Myrtle AFFECTED
Rhodamnia Malletwood or “Turpentine” BADLY AFFECTED
Rhodomyrtus “Native guava”, finger cherry, rose myrtle AFFECTED
Rhistantia
Sannantha (were called Baeckia, Babingtonia...)
Sphaerantia
Syncarpia Turpentine
Syzygium Lillypilly, including riberry
Thaleropia
Thryptomene
Triplarena Heath Myrtle (Was Baeckia)
Tristaniopsis Water gum, Kanooka, includes “Luscious” and other cultivars.
Uromyrtus Includes “Weeping Beauty”
Verticordia Feather flowers
Waterhousia Includes weeping lillypilly, “Sweeper”...
Welchiodendron
Xanthostemon Penda AFFECTED


Native to other parts of Australia - a shortlist.
Popular plants in gardens include:
Agonis Willow myrtle, “After Dark” AFFECTED
Chamelauceum Geraldton Wax AFFECTED
Darwinia
Euryomyrtus Rosy Baeckia
Thryptomene
Tristania neriifolia Water Gum AFFECTED
For a full list see
http://www.dpi.qld.gov.au/documents/Biosecurity_MovingPlantsAndPlantProducts/Module-3-genera-in-myrtle-rust.pdf
Myrtle rust has not been found in Tasmania. Let’s be very careful about not taking it there. In the worst -case scenario, it could become the only place where some of our now-common Australian plants survive in the wild!

Native to other parts of the World - a shortlist.
Here are some foreign Myrtaceae which are seen in Australian gardens.
Eugenia Brazilian cherry, Surinam cherry
Psidium All guavas AFFECTED
Syzygium jambos AFFECTED
Metrosideros New Zealand Christmas Tree AFFECTED

See http://www.dpi.qld.gov.au/4790_19789.htm for details on all Myrtaceae species affected so far in Australia, including information on which are the most highly susceptible.

Thursday, July 7, 2011

Native Geranium

Geranium solanderi
FAMILY: GERANIACEAE
This little native wildflower is very common on our local red soil. While its best display of flowers occurs in spring and summer, this plant was flowering last week on Mt Peel.
It grows from a perennial taproot, and looks its best in a garden situation if it is cut back once a year and allowed to regrow. I usually do this in winter. The plants get straggly, particularly after frost.
The taproot is said to be edible, if roasted.

Hollows



I photographed these two young galahs last weekend, in Nielsen Park in Toowoomba. They were being supervised by two other galahs, probably their parents, as they cautiously made their way out of the family nest.
Neilsen Park is a bit of old-growth forest in the middle of suburbia, and what a valuable place it is.
Not many of us would like to have a Eucalyptus of this size in our backyards, so not many of us can offer nursery accommodation to galahs, or to any of the other 17% of Australian bird species which depend on hollows for nesting. Thanks to the park, the residents in surrounding suburbs can enjoy the advantages of having these birds in their gardens.






I understand that we owe the existence of this park to a Toowoomba family, which gifted it to the city. What a wonderful legacy!
Several years ago it was the subject of intensive weed removal by a volunteer group, the Friends of the Escarpment Parks. To them we owe the healthy regrowth of native shrubs and trees which were able to get established as the weeds reduced.
Weedy regrowth is becoming evident, though, and further work is needed. There just aren’t enough volunteers to go round.