Weeds of Sydney

[philinsydney]

I am in a volunteer bushcare group that seeks to replace weeds with natives, so I thought it would be fun to show some of our most troublesome weeds.

Anredera cordifolia Madeira vine. If any plant could be called evil, this is it. Aerial bulbs can drop to the ground and germinate even after the roots and lower stems of the vine have been removed.

[philinsydney]

Ageratina adenophora crofton weed Can be poisonous to stock

[philinsydney]

Arundo donax giant reed. Sometimes this is not removed because it helps to stabilise creek banks.

[philinsydney]

Asparagus aethiopicus  A very familiar weed: fun to dig out.

[philinsydney]

Bidens pilosa cobblers pegs  Has unpleasant burrs which cling to your clothing.

[philinsydney]

Cardiospermum grandiflorum balloon vine.  Can overtake stream banks and smother everything.

[philinsydney]

Ehrharta erecta panic veldt grass  Probably the most persistent weed in Sydney; virtually impossible to eradicate because it seeds continuously and can be spread by wind, water or soil movements.

[philinsydney]

Ipomoea indica  morning glory    Can be devastating in coastal areas, swamping all other vegetation for miles around..

[philinsydney]

Phytolacca octandra inkweed

Edited March 17, 2021 by philinsydney
wrong photo

[philinsydney]

Ligustrum sinense small-leaved privet  Forms extensive thickets

[philinsydney]

Senna pendula cassia  Forms dense thickets

[philinsydney]

Solanum mauritianum   wild tobacco  Has a nice smoky smell to the leaves but can be toxic in large quantities

[philinsydney]

Solanum nigrum blackberry nightshade

[philinsydney]

Thunbergia alata black eyed susan

[philinsydney]

Vinca major  

[philinsydney]

Verbena bonariensis purple top

[philinsydney]

and of course there are many more....

[sandgroper]

9 hours ago, philinsydney said:

and of course there are many more....

Good on you mate, you do a great job you blokes (and Ladies). 

[Silas_Sancona]

17 hours ago, philinsydney said:

Ligustrum sinense small-leaved privet  Forms extensive thickets

 

Hate anything/everything Ligustrum, lol.. While likely not as big of an issue here in the U.S west as in other places -yet-, you will encounter occasional specimens popping up near creeks/ other moist areas in California.. possibly other areas. Really nasty invader in Florida. Native " Privets " ( Genus Foresteria ) are much tamer/ less aggressive.

17 hours ago, philinsydney said:

Thunbergia alata black eyed susan

 

 See these popping up here and there, primarily in disturbed areas in older neighborhoods/ near train tracks. Can't remember spotting any in more natural areas though.

17 hours ago, philinsydney said:

Vinca major  

 

Quite a common invader almost anywhere it is moist in lower elevation areas of California.. Occasional in a few locations here in Arizona. Think it ( and/or Vinca minor ) is also quite a problem in some of the U.S eastern States. Real hard to get rid of too.

[philinsydney]

A few more:

Erigeron bonariensis fleabane

[philinsydney]

Cytisus scoparius broom

[philinsydney]

Phytolacca octandra  inkweed

[philinsydney]

Ochna serrulata  mickey mouse plant.     Difficult to dig out because of a horizontal kink in the taproot. Also very tough; it takes a lot of poison scraped along the stem to kill it.

[philinsydney]

Lantana camara    Can be useful in preventing drying winds from entering rainforest. Also habitat for small birds.

 

Edited March 18, 2021 by philinsydney
wrong photo

[greysrigging]

Here is a list of Declared weeds in the Northern Territory
https://nt.gov.au/environment/weeds/weeds-in-the-nt/A-Z-list-of-weeds-in-the-NT

[philinsydney]

You'd get plenty of weeds in your climate.

[Silas_Sancona]

We've got more than our fair share of nasty weeds here.. Sahara Mustard, buffelgrass.. and related X- plitive Fountain Grass that some nurseries still sell, various annual pasture grasses from Europe.. Salt Cedar ( Tamarisk ) and the evil Camel Thorn ( Alhagi pseudalhagi ) that can push up through pavement, & concrete ( inc. the foundations of homes ) and is a real challenge to control/ eradicate but the plant below may be just below Buffelgrass in terms of how much damage it may do to the desert itself since it spreads very quickly by tiny seed that either is blown around, or sticks to stuff.

When i moved to where i'm currently located, the Alfalfa field/ abandoned construction site around the corner to my west had none of the stuff.. After the wetter winters last year and in 2019, the stuff is everywhere, even making it's appearance in the yard. Stinks and the resinous compounds produced makes the stuff extremely flammable once it dries out. Also can cause skin / respiratory issues. Hearing it is continuing to spread across California, and in Victoria Australia as well.  EVIL

Stinknet / Globe Chamomile, Oncosiphon piluliferum


Really not sure how it can be completely controlled since applying herbicides out in the desert is a very bad idea and you'd have to attack patches of the stuff before it tries to go to seed.  I'm sure there are also people who would allow it to grow in their yard since they might find it attractive. ( Not me, lol )

[philinsydney]

The daisy family has a lot of culprits, but it is a large family with 30,000 species so I guess it isn't surprising.

Buffel grass has become naturalised in our drier regions as well.

[philinsydney]

The fleabane scientific name should be Erigeron sumatrensis.

[tropicbreeze]

14 hours ago, Silas_Sancona said:

..............I'm sure there are also people who would allow it to grow in their yard since they might find it attractive. ( Not me, lol )

Sometimes wonder if ignorance can really be bliss. I've spent a big part of my life chasing and controlling weeds and recognise them almost instantly wherever I go. Most other people don't know what they are and go about blissfully not noticing them. I on the other hand keep seeing evil, noxious weeds everywhere.

[tropicbreeze]

15 hours ago, greysrigging said:

Here is a list of Declared weeds in the Northern Territory
https://nt.gov.au/environment/weeds/weeds-in-the-nt/A-Z-list-of-weeds-in-the-NT

Interesting how Pistia stratiotes is listed as a weed in that list, however the Darwin Herbarium lists it as an NT native. I know Queensland (and possibly NSW) list it as a weed. I agree with the herbarium.

[Silas_Sancona]

2 hours ago, tropicbreeze said:

Sometimes wonder if ignorance can really be bliss. I've spent a big part of my life chasing and controlling weeds and recognise them almost instantly wherever I go. Most other people don't know what they are and go about blissfully not noticing them. I on the other hand keep seeing evil, noxious weeds everywhere.

Probably true in some cases.. You'd be hard pressed to tell anyone to get rid of the Annual Cape Marigolds people plant for easy, annual spring color here.. I even let 'em live, lol.  In others, i have noticed it comes down to 1 of two things:  1, People simply don't care, and get that frustrated look when you explain why planting X plant is probably a bad idea/ offer alternatives..

2, Some nurseries that refuse to do their research or are stuck on old, out-dated plant options.. including offering those that show clear invasive potential. Noticing that aspect is changing, for the better though more environmentally conscious people take up the hobby, and nurseries already ahead of the curve in that respect gain more recognition/ business than the traditional nurseries. Still a ways to go though. 

As mentioned, there are several great native alternatives to traditional Privets ( Ligustrum ) for people to choose from/ nurseries to offer in Florida, California, Texas.. etc but, at least in FL. ( and in CA. ) you'll still see Ligustrum for sale.  Same w/ Fountain Grass.. Can't count how many alternative  ..and native/ regionally native ornamental grass options are available, many of them much better looking but, if someone like Martha Stewart features Fountain Grass in some quirky application / on her social media page that starts a trend.. all who follow that will demand the stuff at their local nurseries.  It's up to the nurseries to have the walnuts to say " We don't stock/grow Pennisetum anymore.. May i show you some alternatives ? "

In the bigger picture,  Australia is unique in that because it has been isolated for so long, the ecology across the continent is fairly fragile.. or can be altered easier than say here in the states where there has been an exchange of plants.. and the organisms that keep any un-ruly plants in check,  pretty much from pole to pole, for quite some time. It's one thing for something to make the leap from New Guinea to the top end of Aus. and then slowly move south, over time..  It's another thing entirely for something to arrive there, w/out any checks on it ( which themselves could have an amplified negative effect their new home due to the unique-ness of the area ) from say Africa or South America.

As much as i admire Jacaranda or Royal Poinciana, i get why they have to be controlled where they've become an issue there.. even if some people will still plant them.

[greysrigging]

8 hours ago, tropicbreeze said:

Interesting how Pistia stratiotes is listed as a weed in that list, however the Darwin Herbarium lists it as an NT native. I know Queensland (and possibly NSW) list it as a weed. I agree with the herbarium.

Yes it is Declared in the NT ....dunno how many times I've explained the listing to members of our local FB gardening group....people wanting to buy swap or sell various plants on the Declared lists, most commonly the good old Water Lettuce.  I have read somewhere that its thought to be a Kimberley and/or Top End native......

[Gonzer]

Look at it this way. As long as nurseries continue to sell many of these plants as ornamentals to the unsuspecting public you WILL have job security.

[philinsydney]

A few more to add to the list:

Acetosa sagittata    turkey rhubarb     This troublesome weed produces hundreds of papery seeds.  It has a complex network of underground stems and tubers.

[philinsydney]

Araujia sericifera    moth vine     This vine has a smelly and sticky white sap.

[philinsydney]

Cestrum parqui      green cestrum         This one has a most unpleasant rubbery smell.  It is highly toxic.

[philinsydney]

Cinnamomum camphora     camphor laurel   This is more of a problem up the North Coast than in Sydney.

[philinsydney]

Eragrostis curvula   African love grass   This aggressive grass is taking over large areas in western Sydney.

[philinsydney]

Hedera helix     English ivy