South African Weed Orchid

Hi I have been aware of this “weed” for the last couple of years. I am a member of a community environmental group and we have been pulling it out manually. But this year it has become evident that it has spread rapidly throughout the state of Victoria (Australia).
The agencies whose job it is to monitor invasive pests need to do more and not rely on volunteers to manually remove this weed.
If you are doing observations and see one or 100 of these orchids please record your sighting as an observation so the iNaturalist map may convey to the authorities how widespread the infestation is.
Thanks rokidd

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What is the species? Is it the same as Eulophia maculata, or a different one?

Disa bracteata

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Is it a weed with a high impact on native bushland? From what I’ve seen, conservation groups are putting higher priority on species like Blackberry, Arum lily and Watsonia just because they have a bigger visible impact on native bushland. Weed orchids are extremely common here too, I wouldn’t mind knowing more about their impact and spread

Whilst the agencies should do more. How well funded/resourced are they? I know the funding we have to do the weed work we need to do is not great, which means choosing the highest priority work, relative to the staff hours. If your argument is this work needs better funding I agree.

In the meantime, talking with those agencies about getting better access to gear/training/access to other volunteers is always a good start. Often they have access to knowledge and tech which can make the volunteer side easier (As well as with health and safety to reduce the risk related to such work).

rozkidd, snakesrcool, sebastiandoak

Nice discusssion. Ideal world vs allocation of available resources - money, people, time, broken backs.

but you might have to have an account, login, etc.

We’ve had Disa bracteata (still commonly called Monadenia, the old generic name) in Adelaide Hills for > 25 years. Initially there was a big panic and indignation about this weed. (Why?) Lots of public education and exhortation re: dig out both bulbs with a screwdriver. Hard work! We got caught up in the hype and laboured with that for years on our small (1ha) area, but more recently I’ve been squirting them with standard recipe roundup, (two downward squirts, one each side of the flower spike) which kills or disables this year’s visible flower head, and seems to kill the underground bit, because my flagged and squirted plants don’t come back next year.

In the big picture, because money & time is limited, I do spend lots more time on Montpellier Broom, blackberries, olives, spanish heath, which are structural - ie you can’t walk through them. And so do Government & Vol land managers. At the same time, the council mows roadsides just after xmas, for maximum seed spread ;-(

Also in the big picture, the other 99.999999% of the district that I don’t clear of Monadenia don’t seem to be suffering in any way. And for some reason, once an area is infested it doesn’t seem to get more infested in subsequent years. With no formal research, I’m wondering if there’s a biological control, such that the initial infestation expolodes, and then supports its own predator.

So overall, join me in our indignation, but don’t waste your energy on them.

Of course, if anybody disagrees and has other information, plz comment.


Thanks to everyone who has replied to my post. My concern is that the “weed” orchid may crowd out our native orchids. I feel as though I am seeing fewer and fewer of the native orchids, so we don’t need another reason why the native orchids are no longer seen in the bush.

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Another South African plant which is an alien problem is Carpobrotus edulis - yesterday I read about scientists looking for (and finding) potential biocontrol here. Perhaps work with South African scientists for the (alien) orchid.


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