I hate Acacia baileyana. It is ugly and it has a stupid face. Well actually it can be an extremely pretty small tree, but I can't help looking at it and cringing, thinking "bleugh". This is because in the Mount Lofty Ranges it has become an environmental weed, vigorously spreading itself about the place out-competing local species.
If I were to look at it more objectively, I'd admit that it puts on a very nice show indeed, and the contrast of the flowers and leaf colour is quite pretty. I'd also comment that the bipinnate true leaves of the plant are really quite attractive. But for me, when it comes to Acacias, this is phyllode country! Get out of here with your nasty true leaves, you dirty immigrant!
I'm such a speciesist.
We sell a form of Acacia baileyana at work, with a prominent purple tinge to the leaves and the desirable characteristic of setting a lot less viable seed. "Just lovely", I'd say to a customer. "Donkey balls!" I'll say to you, "plant something local instead, you have plenty of fantastic options".
Two more pet hates of mine are Melaleuca armillaris and Eucalyptus platypus. Both planted extensively under the philosophy that a native is a native, no matter which part of the continent it is from, which was widely subscribed to up until the 90s when it started to lose traction. There are still a lot of people who don't know any better who want to plant them as windbreaks, or as a "fast-growing screen".
These two plants grow quickly, are both adaptable to most South Australian conditions, and a more objective observer might concede they are pretty. But to me they are ten years of growth away from either suddenly falling apart, or coming out of the ground in a strong wind and rolling down the hill like a giant tumbleweed. The number of people who have come forward to me with stories like that is fairly impressive.
There is a real disconnect here between my love and acceptance of short-lived local species, such as Acacia pycnantha, and these two short-lived interstate species, though I will argue that the former brings a garden to life and the latter are unfit for purpose and better replaced with something else.
Hakea laurina and Acacia iteaphylla are two species that we no longer sell due to their weed potential. Both are regular problem escapees in the Mount Lofty Ranges, and both have at least one customer per week asking for them. While the former is a Western Australian species (dang show-off of a plant, no surprises there), A. iteaphylla is actually a South Australian species from drier climes, quite rare in its natural range which includes the Flinders Ranges. Odd that it has become a problem such a short way from home.