I went for a walk in the closest patch of wild scrub/forest from my place. 4 kilometres. It was mined for gold 170 years ago but is probably a bit too difficult to turn into a residential area. It is also an area that speaks loudly of introduced plants. 
Most of the trees you can see are native – at least in this photo.
But here is a Monterey Pine (Pinus radiata) from California. This tree is grown in huge plantations in Victoria and South Australia and supplies the building industry with most of its construction timber.
- It is a threat to Mediterranean ecosystems worldwide and in Australia it invades a wide variety of open dry ecosystems.
- Seeds are equipped with wing like structures and can travel up to a km on the wind as well as being dispersed by native wildlife such as Yellow Tailed Black Cockatoos.
There is a small acacia seedling that might survive next to the pine.
On the forest floor the evidence of introduced plants is extreme.
In the bottom right hand corner is some Spanish Gorse (Ulex europaeus) and on the left is Montpellier broom (Genista monspessulana): Lauded in English and American Garden guides as one of the most reliable shrubs for hot and dry sites gorse is a major pest in Australia and New Zealand. It was introduced to Australia as a hedge plant in the early 1800s, but, like cats and cactus and pigs and donkeys and camels and a host of other things that were considered benevolent, it quickly spread out of control. In Tasmania gorse has rendered many hectares of land in the Midlands useless for grazing. It is one of New Zealand’s worst weeds. Its nitrogen-fixing ability means that it tends to inhabit areas with poorer soils where other plants find it hard to survive.
A lot of work, world wide, to find a biological method of controlling the gorse has been tried. But the task is huge and has shown little progress to date.
It also makes a great web building site for small spiders.
That’s enough of me going on and on. Just enjoy the rest and if you see an introduced plant then you are welcome.
The butterfly below is the inventively named Common Brown (Heteronympha merope).
Paol Soren 
We have been told to kill the accidentally introduced Harlequin Ladybird, but I haven’t managed to kill a single one yet. I just can’t do it.
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Take my word for it John. If I had a magic wish and could choose just one animal or insect to destroy I would kill every cat in the country. I think that if the Harlequin Lady bird is as dangerous to Britain’s insects as they say it is, then tough up and stat killing.
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Thanks for that. I have difficulty in thinking things through to a conclusion. Tree and plant species have been and still are being introduced. Bad thing? Recipes and foods are introduced from other countries. Good thing? People are introduced from other countries. Good or bad? Moral standards are shifting with thoughts introduced from where? And so it goes on. You talk about cats in one reply and feral cats are a problem. I love cats and I love the variety of foliage that you have shown. I do like Chinese food. I don’t like chonkee apple trees, introduced from China.
I do love the variety of plants you’ve shown and I particularly love the butterfly, is it native?
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Yes it is native and I think cats are beautiful but they are deadly and responsible for more damage than their beauty is worth.
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Natural habitats the world over seem to be best. That butterfly is well camouflaged.
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The worst introduced animal that I know of is the cane toad. Cane toads became pests after being introduced into Australia to control destructive beetles in Queensland’s sugarcane crops. Cane toads are capable of poisoning predators that try to eat them and they continue to spread across Australia. One of the stupidest things introduced. Even worse than the rabbit which we do not have up north – thanks to the rabbit proof fence – but that’s another story.
But I do enjoy your photo wanderings.
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I agree that cane toads and rabbits are bad, but cats are everywhere.
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Cats are the big problem.
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So how do we deal with it? Too many people with cuddly cat curled on the end of the bed will never allow us to get rid of them
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I’d remove dogs, they don’t seem to me to add any value and they mess the pavements and bridle paths.
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I am aware of your attitude to dogs Andrew but seriously they are nowhere near as bad as can
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There are some bad things about cats I agree, like indiscriminate killing of birds but they are good for getting rid of mice and unlike dogs they never pester people and frighten them (except man eating tigers that is). Another thing that I would get rid of is wasps.
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You’ve stirred up a hornets nest here by putting a cat among the pigeons.
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Ha Ha
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Wow! Your writing is so interesting, and the photographs…! What an eye you have for a good image. I can’t think why I don’t come here more often – I’ve seldom read more interesting or refreshing posts. So now I’ll try and visit more. Silly not to, really. :-))
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I am very pleased that you have come. Sometimes when I write something I have a single person in mind. And everytime I think of Fran Macilvey I remember reading The Poisonwood Bible (1998), by Barbara Kingsolver. I know the only connection is The Congo, but . . .
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