Weeds CRC: Enviroweeds Archive Titles

Please click on a letter to list all weeds in archive beginning with that letter.

Ecballium elaterium - Squirting cucumber
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Date: Wed, 04 Feb 2004
From: Sandy Lloyd <slloydagric.wa.gov.au>

Does anyone on the list have a problem squirting cucumber (Ecballium elaterium)? It seems to be uncommon and, if present, most likely to be on a railway line.

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Date: Wed, 04 Feb 2004
From: Jeff Smith <jeffsmith64hotmail.com>

I have seen the squirting cucumber in the systems garden at Monash University some years ago. From memory it didn't seem to be a problem, except like most of those plants it grew rather large very quickly.

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Date: Wed, 04 Feb 2004
From: Richard <richard@weedmanager.net>

I have seen a few large plants here in Melbourne in the Western Suburbs on road reserve, quite large plants as well.

Echium candicans - Pride of madiera
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A colleague of mine has just noticed that the latest edition (Issue number 25, May 2005) of the (sydney) magazine (attached to the Sydney Morning Herald) has a gardening article entitled surf'n'turf (page 115) which details the use of Echium candicans (Pride of Maidera) in a recreation of a "Tuscan villa garden" in Sydney. The article also suggests that people look out for a new cultivar "cobalt towers" which is a cross between E. candicans and E. pininana.

From a weed perspective the Echium genus is bad news. Many would be familiar with Echium plantagineum and E. vulgare i.e. Pattersons curse, salvation Jane and/or vipers bugloss. Importantly, Echium spp (i.e. the entire genus) are declared noxious weeds (W3) in 53 local government areas of NSW including 6 in the greater Sydney region.

References to the weediness of the Echium genus can be found in Rod Randall's Global Compendium of Weeds as well as Adam Muyt and Kate Blood's fine Environmental Weed books among others.

My colleague is going to gently suggest to the magazine editor that recommending noxious weeds to the public is a bad thing. I'd love to see someone senior with a bit of clout in environmental organisations (or even the CRC?) comment to the paper as well.

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Your colleague's 'gentle' suggestion may be enough, but it'll be worth keeping an eye on the mag. The Weeds CRC is already making a habit of sending letters to editors, either privately or to the letters section to comment on the latest dubious recommendation by gardening writers. An account of what has been recommended in recent months around the country would make an entertaining but alarming paper at a weeds conference! The role is something of a balancing act, as experienced garden thug watchers know, since you want the media to lift their game and not just get the irrits with you and your organisation and carry on regardless. We've been making a point of sending positive letters to editors as well whenever they publish a good weeds article - and there have been some really good ones lately. Some of the better mags have now got into the habit of ringing us for a quick check on certain plants, which is a good development for everyone. Over the next 12 months we'll also be rolling out a project to get some of these messages and associated information directly to writers in the hort/landscaping/nursery industry. In the meantime, drawing the attention of Enviroweeders to the media bloopers out there does help us to respond...mostly gently, but with the occasional rocket.

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Echium candicans or 'Pride of Madiera' is a fairly innocous species by comparison to Echium plantagineum or E. vulgare. It has naturalised in Tassie as it does prefer cooler climes but its habit and massive tower of flowers make it very easy to find and I doubt it will ever become a real problem.

Hybrids of Echiums can be a concern and currently a hybrid between Echium wildpretii x pininiana is considered a quarantine weed by AQIS as is Echium pininiana itself. As the hybrid combination of E.candicans and E. pininiana has not been assessed it may be pre-emptive for the magazine to alert people to its appearance. However I've not been able to determine what the parent/s of the cultivar "Cobalt Towers" is. Its very common for the nursery trade to confuse hybrids with varieties or selections and I take such claims with a grain of salt to be honest. but here is a pic if your interested http://www.pbase.com/image/23073834 I doubt these would be hard to find anywhere.

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I have been observing the very tall Echium species increasingly featured in various gardening and lifestyle magazines. A number of them do spread.

Apart from Echium plantagineum and E. vulgare, here are a few of my notes on other species from various publications and comments from Randall Robinson a while ago:

E. candicans invasive in NZ and sparingly in Vic (basalt cones around Camperdown). This and several other "tree echiums" or "honey plants" from the Canary Islands becoming very popular garden plants due to striking appearance and ease of culture.

E. wildpretii, a biennial with deep pink flowers and velvety grey leaves, self-seeds freely in gardens.

E. italicum is invasive in NSW and SA and is like a slender E. vulgare with creamer flowers.

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In Mordialloc I have recently grown Echium candicans and Echium virescens ssp virescens in our sandy front garden (which is a bit like seed raising mix admittedly). I have pulled out both species because one has provided vigorous and dense seedling recruitment (and also because I didn't like the particular hue of my Pride of Madeira). I'm removing each cohort as it regenerates from the soil seedbank, though I probably should let one grow on a little so that I can determine which is the offending parent. At least one of them could be an environmental weed in certain situations. Looking at where new plants came up, I'd say dispersal was no further than about a metre from the plant.

I know the population of Echium candicans in Camperdown - the plants are on the side of a volcanic cone which is a mix of clay/scoria. From memory the location suggested to me 'garden rubbish' was the original source. I could be wrong.

I think there is clear potential for ornamental Echium spp to regenerate in large numbers at disturbed sites/on mineral soils. I wouldn't plant them in the vicinity of bush. Based on the dispersal pattern I have seen, I suspect they are a non-issue in the heart of the degraded urban environment.

Echium plantagineum - Paterson's curse
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While working on a project site in central Victoria recently, we identified some unusual looking Pattersons Curse (Echium plantagineum). The growth habit was unusual, as the individual stems of the plants are not separated, giving the plants a wall-like appearance (i.e. fasciated).

Chemical testing of the soil onsite for a wide range of analytes, including metals, monocyclic aromatic hydrocarbons (MAH(BTEX)), total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), phenols, organochlorine pesticides (OC), organophosphorous pesticides (OP) and phenoxyacetic herbicides did not return any analytical results at concentrations of concern. All analytes, apart from some metals and TPH results were at or below the laboratory reporting limits.

Can anybody tell me why these plants have this appearance? I could email a photo to you if this helps (not attached due to file size).

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Fasciated growth is normally caused by insect damage of growing tip of the plant when young, its particularly common in Echium plantagenium, I've seen this growth form many, many times over the last 20 years. Its not uncommon in weeds that shoot a flowering stem later in the season.

I've even seen a fasciated climbing Drosera sp. in pristine shrublands at Enebba back in 1983, looked like a bright green belt about a metre long and a 3-4 cm wide.

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I have seen examples of fasciation in thistles, particularly Scotch thistle (Cirsium vulgare) in NZ pastures a few times. The perceived wisdom was that it was caused by low levels of phenoxy herbicide but this seemed extremely unlikely due to a range of factors. In the most extreme example, the thistle stem was 550-600 mm wide x 80 mm thick and the plant was 2 m wide x 2 m tall.

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Date: Tue, 17 Feb 2004
From: Stephen Selden <sseldenozemail.com.au>

Just thought some of you might be interested in this story from ABC News Online (Rural).

Paterson's Curse a salvation? Researchers have discovered health benefits in one of the country's most notorious weeds.

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The Australian is keeping up the good work with a piece on Paterson's curse today

To combat curse, bugs lesser of two weevils
By Asa Wahlquist, Rural writer
January 09, 2004

Paterson's curse exploded after the drought, cloaking southern pastures with purple and consolidating its status as Australia's worst pasture weed. The toxic plant chokes out pasture grasses with its dinner plate-sized rosettes of leaves and, in the Australian Capital Territory alone, 80 horses have died from eating it.

A solution is in the breeding of insects, such as weevils and beetles, although according to Matthew Smyth, national CSIRO co-ordinator for the bio-control of Paterson's curse, "A lot of people doubt bio-control, because you release the insects and 12 months later, they say 'well it hasn't done anything'.

"But you come back to a property 10 years later when 1000 insects have turned into a billion insects, and it gives them an idea of how long it took, what the grower did to get the insects started."

He says those who doubt the tiny weevils and beetles can control a weed that costs $100million a year in lost production, "instantly become converts when they see swarms and swarms of insects just chewing plants".

In 1971, the CSIRO opted for bio-control. So far, they have introduced six insects.

In South Australia the plant provides grazing in drier regions and beekeepers love the abundant neutral honey it produces. Not surprisingly, an injunction from some South Australian graziers and apiarists delayed the introduction of the first bio-control for eight years.

The first insect, a leaf-mining moth, introduced in 1988, did not do much damage.

Next, a weevil that attacked the crown, or the growing point of the rosette, was released in 1992, followed by a root-eating weevil in 1996.

"We have growers now who don't spray for Paterson's curse because the crown weevil is doing the job for them," Mr Smyth said. "It's great to see that over a 10-year time frame you can go from an intractable weed problem to a manageable one."

With the weevils now proven and well established on a handful of sites, the next task is to spread them far and wide.

The process is simple. "All you do is hit the flowers with a stick, the weevils fall into a tray and then we suck them up with little hand-held vacuum cleaners," he said. "At a field site at Yanco we collected 100,000 weevils doing that.

"Each year we see an increase in the range of the insects that are released," he said. "The newer species are becoming more and more abundant and more and more damaging, which is the ultimate goal."

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Date: Wed, 14 Jan 2004
From: Stephen Selden <sseldenozemail.com.au>

This looks like a good idea. I tried to find out more on the net but was not successful.

In New South Wales the racing industry has set up a register to try to determine how many horses have died or become sick from eating Paterson's Curse, also known as Salvation Jane.

The weed contains an alkaloid toxic to horses, and veterinarians have reported dozens of horse deaths across the ACT and southern New South Wales.

Paterson's Curse spread in epidemic proportions as a result of the drought and last year's bushfires.

Spokesman Craig Suann says the register will help industry work together to deal with the escalating problem.

"Obviously we're concerned primarily with thoroughbred horses, but we're also interested to know of other horses that might be affected. If we're going to have some sort of coordinated response in trying to determine the nature of the problem and how we can go about solving the issue for future occasions, we need to have all stakeholders involved so that we can have a multi-pronged attack."

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Just thought some enviroweeders might be interested in this story off ABC News Online about the HORRIBLE problem we are having with Paterson's curse in the ACT and Southern NSW.

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I encountered an interesting patch of (Paterson's Curse) Echium plantagineum the other day. It contained approx. 30% white flowering plants, including one very interesting (should that be fascinating) fasciated (white) one. On closer inspection I then discovered many dark crimson flowering plants. I also think there were other colour variants (- e.g. more and less pale blue fringing of the 'normal' colour flowers). As I was actually trying to find some rare native plants at the time and check a site for Growling Grass Frogs I did not spend too much time studying the plants!

The plants are growing in damaged native grassland (Northern Melbourne - Merri Ck i.e. basaltic soil) possibly on some fill on a mown firebreak adjacent to the perimeter fence of a landfill. Who knows what the chemical history of this patch is!?

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White Echium plantagineum flowers are not that unusual and the colour range I've seen varies from deep purple through to mauve and almost pink. I've spent way too much time amongst the stuff. The species fasciates easily, we found a beaut once that looked like a huge fat belt almost as tall as a person.

We did have one chap in our dept who thought that Paterson's curse was going to become an even bigger weed in white flowered lupins by becoming exclusively white flowered. Not sure why he figured this, I don't know any farmers who hand rogue lupins, but heh!

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Years ago (maybe 20 yrs ?), Jeremy Burdon and Richard Groves (both of them with CSIRO Plant Industry and the Weeds CRC) did a formal study of colour variation in Echium plantagineum.

Pomategon crispus -Curly Pond Weed
Vallisneria gigantea - Eel Grass
Water Hyacinth
Salvinia molesta - Salvinia
Ludwigia longifolia - Ludwigia
Elodea
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Recently there have been many news items about serious infestations of water hyacinth in rivers in central and southern Queensland including the Brisbane river above Savages Crossing. People may not be aware that in the past the Brisbane river used to be regularly blocked by water hyacinth, as was the Bremer river and the various creeks feeding into the rivers. When there were floods, the mats of plants coming downstream used to completely block the Brisbane river in the city reaches, piling up against the Indooroopilly and city bridges. There are photos in the State Library and Courier Mail archives from 1909, 1928, and the 1960s, with the last big event of this sort in the 1974 floods.

Subsequently two weevils, Neochetina eichhorniae and Neochetina bruchii, were introduced by CSIRO in the 1970s and 1980s, and gave pretty good control of the weed in most areas, which is why there were no mats of water hyacinth coming downstream in the minor flood events of 1992.

However, it seems that with recent prolonged low river flows plus very hot weather very late in the season, plus high nitrate levels from fertilizer and other contaminants, the water hyacinth is growing too fast for the beetles, and the result is major infestations again. South Africa has experienced the same problem, for just the same reasons, and ten years ago they imported a new insect, a small mirid called Eccritotarsus catarinensis, from Brazil. At a recent international conference they reported on the success of this bug, which – working together with the earlier weevils - has given excellent control of water hyacinth even in low-flow and highly polluted waters. Details will be published in the conference proceedings later this year.

As this was also in tropical and sub-tropical areas, the mirid should work just as well over here, and I would strongly encourage people working with water hyacinth control to start putting together some funds to bring this insect over here. As it has already been thoroughly tested for South Africa, very little extra work would be needed, and the costs should be minimal. The work could be done by the Queensland Government Biosecurity weed biocontrol unit in DPIF or by CSIRO Entomology, and should not take too long to start getting results in the field. So let's go for it, and get this problem under control again!

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Rachels email on water hyacinth biological control is certainly a timely reminder that there are potential new options out there for water hyacinth management.

However, Eccritotarsus is not an option for Australia. It was comprehensively tested by John Stanley and Mic Julien at the CSIRO quarantine facility in Brisbane (Stanley and Julien, 1999: Biological Control 14, 134-140). It was shown to perform equally well on the 3 (of 4) native Monochoria species tested under laboratory conditions. I can provide the manuscript that summarises this work to those who are interested.

Nonetheless, the search for new water hyacinth agents continues (driven largely by USA and South Africa), as there are a number of important situations (e.g. very high nutrient; low stream flow) where the existing agents are generally not sufficiently damaging.

Among the agents currently being considered, one of the most promising is a sap-sucking bug, Megamelus scutellaris (Homoptera: Delphacidae). It is highly damaging in the laboratory. Host-specificity testing is ongoing in Florida (being conducted by USDA), but results are encouraging: it has not really attacked other plants in the family that have been tested so far. USDA has kindly offered to include native Australian Monochoria species in their testing (these are the most likely native species to be attacked), and we are currently sourcing these. Please contact me if you have access to any of the native Monochoria species (M. vaginalus, M cyanea, M. australasica or M. hastata).

Rachels main point is therefore correct: there are exciting new opportunities on the horizon (next few years) for water hyacinth in Australia, and they are likely to be relatively cheap to capitalise on given the work being done overseas.

Please contact myself, or your contacts in QDPI (e.g. Gabrielle Viviansmith, Bill Palmer) or the National Aquatic Weed Management Group (e.g. Andrew Petroeschevsky) if you have any suggestions as to how such a project could be developed and funded in the medium term.

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I have just been asked what species of weevil is being used to control salvinia in the Hawkesbury. Can anyone help? I have not been able to track this information down.

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Media Statement
3 Baron-Hay Court, South Perth, Western Australia 6151
Tel: (08) 9368 3641 Fax: (08) 9474 2018

A grower near Denmark has unwittingly used the declared aquatic weed salvinia as a mulch and fertiliser for olive trees, having mistaken it for a plant commonly called duckweed.

Department of Agriculture project manager plant pests Ted Knight said salvinia was a declared weed in Western Australia because it could rapidly spread and choke ponds and waterways.

"This was a case of mistaken identity. Salvinia was being grown in small dams on the property and harvested as a natural mulch and fertiliser for organically grown olive trees on the same farm," Mr Knight said.

"Chemical treatment of the weed in this case is not an option because the farm produce is grown organically. The owners have agreed to physically remove all of the weed from the dams."

Mr Knight said the owners could consider replacing the salvinia with the native species, azolla, which is similar in appearance to salvinia but is not as aggressive in growth or weed potential.

Salvinia and other aquatic weeds, such as water hyacinth, hydrocotyl, lagarosiphon and alligator weed, are all declared weeds in Western Australia which means they must be destroyed when found.

All of them can spread quickly, form dense mats which block light for fish and other plants and have the potential to block up rivers, waterways, irrigation channels and dams, and overtake wetlands.

"In this particular find of salvinia, there was real potential for spread as a large dam was nearby that had an outlet to lower ground, wetlands and waterways," Mr Knight said. "It would be very damaging to an environment of rushes, shrubs and trees if chemical control was attempted.

"Salvinia is also easily spread because parts of the plant regenerate. A duck with parts of the plant attached to its feet could easily spread it to another area."

Mr Knight urged people to report to the Department of Agriculture any suspect aquatic plants, especially those that appeared to be spreading rapidly.

He said most salvinia infestations were likely to be found in backyard ponds and on residential blocks. Plants from an aquarium, water feature or pond must not be disposed of near any waterway or drain.

Further information about salvinia and aquatic weeds can be found online at www.agric.wa.gov.au

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(1) Pomategon crispus (Curly Pond Weed). Growing in a 'duck pond' constructed in a natural wetland. Worth worrying about? If so, what are the control options?

(2) Vallisneria gigantea (Eel grass) Looking to eradicate this one. Infestation is smallish and filling in the ponds is an option. However the ponds are connected to a major river and are thought to provide fish refuge. Any thoughts?

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The latest media release from WA Department of Agriculture fyi If you're in WA and you spot water hyacinth or any other declared aquatic weeds such as salvinia, PLEASE let us know about it - in country araes call your nearest office, in Perth call the South Perth office on 9368 3333 or email me the details.

Media Statement
3 Baron-Hay Court, South Perth, Western Australia 6151
Tel: (08) 9368 3641 Fax: (08) 9474 2018
www.agric.wa.gov.au

Inspection officers are making spot checks at weekend markets and swap meets following the discovery of aquatic weeds being sold as water ornaments.

The Department of Agriculture has found water hyacinth being sold at Belmont and Canning Vale weekend markets as a plant suitable for ponds and aquariums.

Department Project Manager Simon Merewether said water hyacinth and other aquatic weeds, such as salvinia, appeared attractive to the public and were unwittingly passed around.

Water hyacinth and salvinia are native to South America. Water hyacinth is a free-floating plant with broad, glossy leaves and lilac flowers on bulbous stems. Salvinia is a free-floating aquatic fern with oval leaves of about 2.5 centimetres in diameter. It thrives in still or slow-moving fresh to brackish water.

Mr Merewether said they were declared weeds and forbidden from being cultivated because they were capable of large scale and expensive damage to waterways and the flora and fauna that live in those habitats.

"When introduced to waterways, water hyacinth grows into a thick mass which reduces fish populations, limits food sources for water fowl, and provides shelter for organisms such as mosquitoes," Mr Merewether said.

"It can also choke irrigation systems, reduce water flow and make areas impassable for boats," he said.

"These aquatic plants were also a threat to humans. Children could attempt to walk on a thick mat of these weeds because they resemble a lawn and drown.

"Some people have cultivated these plants for backyard ponds and aquariums. It is of special concern when the plants are discarded into waterways where they quickly spread."

Mr Merewether said if gardeners wished to dispose of water hyacinth, they should place the plant in a plastic bag to dry in the sun for several weeks. Sightings of declared aquatic weeds should be reported to the nearest office of the Department of Agriculture.

Work orders would be issued requiring the removal of plants within a given time. A free information brochure on declared aquatic plants is available from the Department of Agriculture on 9368 3710.

Media contacts
Simon Merewether, Project Manager9780 6225
Sandy Lloyd, Weeds Research Officer 9368 3760
Alison Blake, Media Liaison Officer9368 3641

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The West Australian has run the water hyacinth story - there is a feedback button if you want to coment on the

WATER hyacinth, an aquatic weed which chokes waterways and kills fish, is being sold for aquariums at weekend swap meets, according to the Department of Agriculture. Project manager Simon Merewether said people risked a $1000 fine for a first offence for selling the declared South American weed. The plant was recently sold at Belmont and Canning Vale weekend markets as suitable for ponds and aquariums. It is free floating with broad, glossy leaves, lilac flowers and bulbous stems. "Water hyacinth grows into a thick mass which reduces fish populations, limits food sources for water fowl and provides shelter for things like mosquitoes," he said. "It can also choke irrigation systems, reduce water flow and make areas impassable for boats." Mr Merewether said thick infestations resembled a lawn which could prompt children to walk on it, sink through the mat and drown. A particular problem with water hyacinth and salvinia, a floating fern also from South America, was when people emptied fish tanks with the weeds which then spread into wetlands. Bayswater City Council spent more than $10,000 this year controlling salvinia which covered about 1ha of wetland beside the Swan River near Garratt Road bridge. It was believed to come from streams flowing out of a nearby residential area.

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I had a request recently regarding the control of exotic water lilies that are dominating an indigenous wetland.

Can anyone please share their experience/s of the most effective controls and timing of these?

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Date: Wed, 18 Dec 2002
From: Graham Prichard <graham.prichardportstephens.nsw.gov.au>

Is anybody out there - working with Ludwigia longifolia (ONAGRACEAE)? I would like to discuss how to manage this plant in waterways and natural wetlands. Any good references would be appreciated.

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We in Sutherland think that we will be dealing with it in the future, so far we have found two plants at different locations. Our current extensive (not) knowledge of this plant suggests that it seems to favour the same areas as L. peruviana, ie creekbank/beds and aquatic margins. I sprayed one with roundup biactive @ 1:100 and it died quite nicely which was pleasing to see. The other plant was cut and painted with neat roundup biactive and that also died quite nicely. This was even more pleasing to see that it can be cut and painted succesfully since L. peruviana will resprout when treated the same way. Of course one plant is hardly a comprehensive trial but I am hoping (praying begging etc) that this will be the case with other plants.

There was a story going round that someone in the Sydney region planted it in a constructed wetland because it went well in wet areas (well it does but thats not the point). Whoever pointed out that this was a bad idea and that it should be removed would probably know more about it for you but unfortunately I don't know who they were.

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Date: Wed, 8 Jan 2003
From: Dale & Martin Morgan <dmor7317bigpond.net.au>

I am in need of some information concerning Elodea. This aquatic weed has infested the upper reaches of the Mullum Mullum Creek in Ringwood, Melbourne. I have watched it become thicker and thicker over the last year, and now with the water level low it is choking the creek badly. Marine life must be having a hard time moving about in there. thanks Dale Morgan Mullum Mullum Creek Bushcare Group

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I am wondering if folks could assist me with specific general information on Salvinia control worldwide. I have reviewed information on the web and am looking for specific information on immediate options for more efficient localized control of Salvinia on the Island of Oahu in Hawaii (Lake Wilson). Efforts to work on biocontrol agents are currently on-going in Hawaii and are not an object of my inquiry (neither are statements such as "ban it" or "don't have in introduced in the first place"). I have been asked to quickly review the relative success or failure of mechanical, chemical, or bio-control techniques for this plant (responses with 24 - 36 hours are appreciated). I am specfically interested in mechanical and chemical means that have worked elsewhere to reduce the problem. Information on specific chemical used to control Salvina locally elsewhere or mechanical means (booms, etc.) would be useful. I would appreciate any general comments, reference citiations, and referral to relevant websites on this issue. Please respond to this message off-line.

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Date: Tue, 4 Mar 2003
From: Graham Prichard <graham.prichardportstephens.nsw.gov.au>

Does anybody know of an article that contains details of the evapo-transpiration rate of floating aquatic weeds being greater than the evaporation from a clear water surface?

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Allen, L.H., Sinclair, T.R., and J.M. Bennett. 1996. Evapotranspiration of vegetation of Florida: perpetuated misconceptions versus mechanistic processes. Soil and Crop Sciences Society of Florida, Proceedings, Volume 56, September 18-20, 1996.

I can send you a copy if you don't have access. They conclude that well-watered, fully vegetated, water surfaces should have ET rates similar to open water. "Since evaporation of water is coupled to latent heat of vaporization, the surface energy balance dictates the bounds of ET rates."

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Having recently discovered Salvinia in backyard ponds in a small community in the south of Sydney I am looking to get a list of acceptable alternatives together that I can advise people to replace it with. I am guessing that either Azolla filiculoides var rubra or A. pinnata would do. Can anyone suggest any other native 'pond weeds' that I can suggest or provide to people (carrot and stick style)? The site is within 200m of the Royal National Park so I am very keen to a) get rid of the Salvinia and b) replace it with something acceptable.

Secondly, late last year I confidently asserted on this forum that Ludwigia longifolia could be killed by cutting and painting it. A recently discovered green shoot from a "dead" stump has proved me wrong. Big smacks for me and please ignore my incorrect information. It is now obvious that L. longifolia does not die following cut and paint treatments (same as L. peruviana - I should have done some research on the genus) and merely plays possum for about six months to trick novice Noxious Weed Officers such as myself into believing that it is dead. Better news is that the plant that was given a folar spray of glyphosate has not resprouted.

Sorry for incorrect information and any hints on the Salvinia alternatives would be most appreciated.

Egeria densa - Leafy elodea
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Media Statement
3 Baron-Hay Court, South Perth, Western Australia 6151
Tel: (08) 9368 3641 Fax: (08) 9474 2018
www.agric.wa.gov.au

Prompt action by a Busselton pet shop owner has helped the Department of Agriculture identify the noxious weed leafy elodea (Egeria densa) in a local backyard pond.

The aquatic weed, which is also known as dense waterweed, has not been recorded previously south of Perth.

Department technical officer Brad Rayner said leafy elodea was a serious threat to wetland environments and had potential to block rivers, waterways and irrigation channels.

Mr Rayner said the weed was native to South America and was prohibited in Western Australia.

"Leafy elodea is an attractive plant which is why it is sometimes found in ornamental ponds and aquariums," Mr Rayner said.

"It is a perennial plant which forms dense mats of submerged vegetation, blocking light and reducing the oxygen levels in the water.

"Fish and other aquatic life are threatened and native water plants can be shaded out."

Mr Rayner said leafy elodea produced summer and autumn flowers with three white petals and yellow anthers.

"Leafy elodea can be easily spread by stem fragments and for this reason it is important that pond and aquarium owners don't discard aquatic plants into waterways," he said.

"Anyone who suspects they have seen this weed should contact their local Department of Agriculture."

Enchylaena tomentosa var. tomentosa - Ruby saltbush, Ruby sheepbush
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I have a client having trouble with enchylaena coming up all over the Kingscote golf course. There is heavy native vegetation along the road verge on one side of the golf course which has a large amount of enchylaena growing in it. I guess the birds are carrying the seed onto the golf course. Some of the patches get quite large before they can be dealt with. Does anyone know what herbicide/s to use which will successfully control this plant. Due to its fleshy nature and fine hairs on the outside of the leaf it may need something additional to break down the leaf coating.

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Golf course managers are rabid mowers and I'd have thought a few close mows would kill them, or does it just grow prostrate and keep on keeping on?

If so, is it all that bad? maybe it could be a low water lawn replacement, golf clubs can be rather conservative at times though, a saltbush fairway may not go down so well...

Epilobium billardierianum - Willow herb
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Date: Fri, 27 Jun 2003
From: Anthony Theunissen<atheunisdarebin.vic.gov.au>

Has any one got any suggestions on how to control Epilobium billardierianum. It seems to be resistant to Round Up. The site is a cemetery where it is growing between grave sites along with other weeds and grasses that also need to be controlled at the same time so a broadleaf selective herbicide would not be appropriate.

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Date: Tue, 01 Jul 2003
From: Lyndal Sullivan <lyndalhermes.net.au>

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Date: Tue, 1 Jul 2003
From: Graeme Lorimer <Ecologyoptusnet.com.au>

The willow-herb Epilobium billardierianum (in the evening primrose family, Onagraceae) is indeed indigenous in Victoria. The most common subspecies is cinereum, which often requires microscopic inspection of seed to reliably distinguish it from the introduced species E. ciliatum.

I suspect that the original enquiry relates, in reality, to E. ciliatum, which is a weed of plant nurseries, gardens and similar places (including cemeteries).

It would be a concern if E. billardierianum were to be targeted in native vegetation, but it seems to me the original enquiry is not about environmental weeds and doesn't belong on this list server anyway.

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Date: Wed, 02 Jul 2003
From: Greg Steenbeeke <gsteenbeekedlwc.nsw.gov.au>

With all due respect, I feel that the issue here is the control of a plant (let's call it a weed) which is growing in a place where it is not wanted. Regrettably it is probably a native, but it wouldn't be the first time something native is treated to this sort of response (consider things like roly poly - Sclerolaena muricata - and galvanised burr - S. birchii - both native, both hated to the extent that one is even listed as noxious!).

Epilobium is a genus of short lived plants (annuals and perennials) that are colonisers of disturbed ground. In north America they are called fireweeds, because that is the situation in which large numbers are usually seen - post fire disturbance. Now a cemetery is pretty high up there on the list of 'disturbed sites', and given the plant's resistance to things chemical, maybe the best means of control is to take to it with the whipper snipper. The only other means of control is to allow the site to get past the 'disturbed' stage, something that is not going to happen.

Eragrostis curvula - African lovegrass
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Has anybody got any idea if granivorous birds (finches, quail, pigeons, parrots etc) can spread grass species such as Eragrostis curvula (African Lovegrass).

Has there been any studies showing the possibilities? Does the birds digestive system destroy the seed? etc

http://www.nrme.qld.gov.au/pests/environmental_weeds/weed_info_series.htm is a link to a fact sheet on it.

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This question has been asked of Sporobolus species many times. The answer I give is that these grass seeds are not like the hard seeds of fruits which pass easily through most birds. Consider feeding grain to hens which easily digest it. The grass seeds of Eragrostis curvula and Sporobolus species would be no different in structure etc than common cereal grains. Generally they are digested by the specialist granivorous

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I agree with Wayne. Granivorous birds are consumers of seeds, very often of grass seeds. Grass seeds themselves are the diet and the crop of the bird destroys the seed. This is NOT the same as with fleshy fruited plants where the flesh is the attractant and the food and the seeds go along for the ride. An interesting parallel case, and an exception that proves the rule, is that of red-tailed black cockatoos that feed on chinee apple (Ziziphus mauritiana). These birds, unlike other species, harvest the seeds from inside the endocarp which is itself inside a fleshy fruit. Black cockatoos are seed predators. In this case, the flesh itself is ignored and the seed is consumed. Most birds, however, that feed on chinee apple take the flesh and either discard the endocarp and the seed it contains or swallow and pass it with viable seeds.

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The reproductive ecology of most weedy grasses, like other opportunistic species, involves producing a huge excess of seeds, of which only a tiny fraction needs to survive to perpetuate the species. Given the vast numbers of seeds of grasses consumed by birds, even if only a minute fraction survive digestion, that would be ample to cause dispersal. To make a valid claim against the dispersal of seeds passing through birds' crops or guts, you should really check whether any seeds at all (even a minute percentage) survive digestion by any of the granivorous birds in question.

However, I think you're barking up the wrong tree if you think that consumption of seeds is the way that grasses might be dispersed by birds. Grasses have a most amazing array of dispersal mechanisms that can use birds. For example, Wayne Vogler mentioned Sporobolus, of which some species produce very sticky seeds that you will find stuck to your clothes if you walk among the mature inflorescences. Any birds that eat the seeds would become coated with seeds that would ultimately fall off elsewhere. The grass 'seeds' (strictly, dispersal units comprising florets, spikelets or clusters) of many other grasses and sedges have hairs, burrs, hooks or velcro that would adhere to feathers of birds, particularly those which forage among the grass.

Wetland species of plants, including grasses, have amazing relationships (often symbiotic) with waterbirds, which disperse seeds over distances that are sometimes huge. Again, it is not the consumption of propagules that matters, but adherence of the propagules to feathers or legs.

To answer Craig's original question, I think birds do indeed disperse certain grass species, and the abundance of some grass species on building ledges and walls favoured by pigeons is a good anecdotal demonstration. Let's not be frugicentric about this; consumption of seed is not the only mechanism for seed dispersal by fauna!

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Date: Thu, 17 Jun 2004
From: Gabrielle Viviansmith <Gabrielle.Viviansmithnrm.qld.gov.au>

FYI, an interesting review paper is available for download on the web by Figuerola and Green (see link below). It discusses dispersal of aquatic organisms, including grass & other plant seeds via ingestion by waterbirds/waterfowl (incl. briefly the different gut physiologies and dietary components that can influence this). It is probably of greater relevance to wetland grass weeds such as Hymenachne, than for Eragrostis curvula, but is still a good source of info.

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An additional way in which birds disperse grass seed is through the deliberate collection of nest material. The nests of finches are often bulky structures composed of grasses. I examined the nest of a Red-browed Finch, Neochmia temporalis, Passeridae, brought to the ground by strong winds. The nest was mainly composed of dry grass and included a large number of Austrostipa seeds, probably A. mollis, which have long twisted awns, some seeds of a wallaby grass Austrodanthonia sp., panicle pieces of Common Blown Grass Agrostis avenacea, a Hairgrass Aira elegans and a native poa Poa ?clelandii, plus some other, as yet unidentified, grass seeds. Some of the panicles pieces held seed. The identified panicle and seed material seemed to be species that were readily available within tens of metres of the nest site.

The gathering and movement of grass panicles and seeds for nesting material could enable more rapid dispersal of seed than by some other dispersal mechanisms. It might enable seed to cross dispersal barriers such as rivers and roads.

Eragrostis curvula has a panicle similar to some native Poa spp., although possibly more wiry and and less brittle. I imagine that the Red-browed Finch would integrate it into its nests when available. Similar considerations apply to seed of Nassella spp. (e.g. Chilean needle-grass) which are similar to Austrodanthonia. Being part of a nest might also assist seed survival and germination, e.g. the finch nest also contained lots of faeces which would improve the nutritional status of the soil when the nest falls to the ground; e.g. grass seed may be less prone to predation if stored in a tree canopy.

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As an aside, from observation I believe that Superb Fairy-wrens move the seed of Ehrharta erecta. This grass regularly appears near my bird bath where the Wrens are the most common visitor.

Euphorbia cyathophora - Painted spurge
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Painted Spurge (Euphorbia cyathophora) does not appear to have been mentioned so far in this list's discussions.

Harden (Flora of NSW) mentions it as a native of South America and "Uncommon on sand dunes near the sea. NC CC SC; Qld".

However it has long been regarded as a serious coloniser dunes on the Far North NSW Coast. One particularly sinister property is that it can survive under deeply shaded forest canopies making it a Littoral Rainforest invader.

Years of attempts to control it with Glyphosate have been fruitless here on the Ballina coast and after a very wet summer and autumn it is now worse that ever seen since dune and Littoral Rainforest restoration began 18 years ago.

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I seem to remember that while spraying Mother of Millions a few years ago with Fluroxypyr that I also killed the associated painted spurge. I think I was using 6ml/L and surfactant (agral) for the Mother of millions but it might be worth trying lower rates (even half) as it was killed very quickly and Fluroxypyr is expensive. I would also check out if other surfactants such as BS1000 would be less environmentally hazardous. You would of course have to ensure that your spraying regime is timed to prevent re-seeding as in my experience this is the key to controlling this weed.

Euphorbia paralias - Sea Spurge
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Date: Mon, 06 Aug 2007
From: Monica Meghan Hersburgh <mmhersburgh@students.latrobe.edu.au>

Does anyone know where some big infestations of Euphorbia paralias - Sea Spurge are located? I am doing an honours thesis on this species and ideally need 10 invaded sites. I know of the ones at Portland and Wilson's promontory, but was hoping for an indication of where others may be before I get in my car and drive the south cost.

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Date: Mon, 6 Aug 2007
From: "Graham Harding" <Graham.Harding@eurocoast.nsw.gov.au>

Thats the south coast of Victoria, due you wish to spread out further to the south coast of NSW?

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Euphorbia paralias is widespread and abundant between Torquay and Lorne. Also check out the beaches around Kilkunda, particularly Shelly Beach.

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John Kershaw may not have visited the Surf Coast recently - thanks to the efforts of community groups and GORCC (the foreshore committee) there is now very little Ep between Torquay and Eastern View. West from there the coast is rocky & unsuitable for much of the way to Lorne, but becomes sandy again & there may be infestations there. Beyond Lorne, lots of rocks again. I do know there is spurge at Castle Cove beyond Cape Otway, but there will be other infestations too. Contact Gary Summers, Parks Vic Ranger at Apollo Bay ph 131963.

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In light of those images I'd like to support Neil Tucker's point that the Great Ocean Road east of Cape Patton (right through to Queenscliff) is relatively clean. There are some small patches around the entrances to some of the estuaries (Cumberland River just east of Lorne is a good example), but mostly it's restricted to a very thin, intermittent line of Spurge just above the high tide mark (except where it's been removed by local community groups).

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Date: Fri, 10 Aug 2007
From: Mark Trengove Ecological Services <mtrengove@pipeline.com.au>

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Can anyone tell me if there are any biological controls that can be applied to Euphorbia paralias (Sea Spurge), a major environmental weed of the coastal sand dunes of southern Victoria?

Also, what systemic hebicides are recommended for its control? Spraying is dangerous to other plants in an environment (coastal dunes just above high water) that is rarely without at least a breeze. Could a herbicide be applied with a 'weeding wand' or the like ?

If you are not familiar with this weed, it is spread by both wind and ocean currents. In southern Victoria, the prevalling winds are south and westerly, whereas the currents are east to west. Thus the sea spurge has a most efficient two way transport system already set up for its seeds to spread.

As a member of the voluntary group the 'Friends of the Prom', I have hand pulled up many thousands of plants, but even with a large voluntary labour force, hand pulling is only efficient in keeping small isolated bays relatively free of the stuff.

The other problem with it is the sap, which some people have allergic reactions to.

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Biocontrol is not that simple - you need to have the weed approved as a target for biocontrol, then identify suitable agents in the native range of the weed, followed by host specificty testing, then consultation, and need approval from AQIS before release

It takes years and costs a packet! this weed is also a problem in the southwest of WA, the seeds are carried by seawater so can spread long distances

Many Euphorbia spp. have nasty caustic sap - you should not handle these plants except with rubber gloves or other protection

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Some time ago there was some discussion re this species following a request from myself. the replies are attached.

As well as adding my twopennethworth to others' requests, I can ask my own too, can't I? Some time ago, we had to remove some Euphorbia paralias (Sea spurge) from dunes at Fairhaven by hand. I tried at the time to find out about sprays, to no avail - I heard about some research done at Cape Otway, but couldn't make contact with the researcher. Any info?

Hi, Euphorbias are controlled by Metsulfuron methyl from Du Pont (Brush off in Aust). Low rates will knock back the whole family. See Du Pont for rates and wetting agent.
Chris.

Neil
Thierry Rolland (Coast Action facilitator) has been doing some trials using flames. He may be worth a try.

Hi Neil
My colleague fwded your email to me.
In the Mornington Peninsula National Park we have been implementing a Sea Spurge control program over the last 2 years. In 1999 we had report produced by Peter Belbin (ph 5989 2466). In the report he listed 2 chemicals which were known to be used for Sea Spurge control: 2,4 D Ester and Metsulfuron Methyl.

The Otway NP 1993 trials were reported by Wilcock 1997 and then repeated by Wilcock in 1997 with 2,4-D Ester.

This work is referenced to Wilcock, P.J., (1997) Aspects of the ecology of Euphorbia paralias L. (Sea Spurge) in Australia. Bachelor of Applied Science Honours Thesis. Centre for Environmental Management, University of Ballarat.

Within the Mornington Peninsula National Park we have used Amicide 500, a 2,4 D Amine chemical. This has proved effective but must be applied with caution, as it does affect off target species. Any treatment must be followed up with hand removal as the regeneration from the seed bank seems to continue annually.

Euphorbia lathyris - Caper Spurge
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Date: Thu, 14 Apr 2005
From: Tracy Michael <tmichael@alburycity.nsw.gov.au>

I'm interested in hearing about any proven methods for controlling Euphorbia lathyris (Caper Spurge). We have quite a number of these plants in a heavily disturbed gully area on public land and they are starting to spread onto surrounding private agricultural land. Glyphosate application has had very limited results, some hand pulling may be an option if we get some good rain, although I'm interested to know if there are issues with this method?

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Date: Thu, 14 Apr 2005
From: Graeme Lorimer <Ecology@optusnet.com.au>

The sap of Euphorbia lathyrus (Caper Spurge) is highly irritating to skin and eyes. Hand removal should not be undertaken lightly, and requires suitable gloves and glasses, and perhaps barrier cream on exposed skin such as the face. Make sure to provide for washing if contact occurs.

A list of herbicides registered for any specific weed can be determined using the search engine at http://www.apvma.gov.au/pubcris/subpage_pubcris.shtml. Enter the weed name in the 'Pest' field and hit the 'Search' button. In the case of Caper Spurge, there is evidently no herbicide registered in Australia. I don't know the legalities that apply in NSW to such a situation, so am loath to provide advice. The usual search engines like Google are often helpful in finding out what other people have discovered.

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Date: Thu, 14 Apr 2005
From: Tracy Michael <tmichael@alburycity.nsw.gov.au>

Thanks Graeme, Google search is always my first point of call, there are lots of weed species lists for various sites and a few comments on the care needed with hand pulling, I guess I was hoping for some more info on whether this method is successful, whether its a necessity to remove the entire root ball, are there any other options etc? The APVMA doesn't list any products registered specifically for Caper Spurge but there are numerous glyphosate based products registered for Euphorbia or Spurge sp.

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Date: Thu, 21 Apr 2005
From: Wendy Moore <woobinda@pipeline.com.au>

Following article from IndigiNotes will be of interest. It may be worth contacting Friends of Warrandyte SP (Vic) for info about success of their work and any other info they have gained.

http://home.vicnet.net.au/~iffa/spurge.htm

Eulophia graminea - Cheating Orchid
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From: Richard Denver <richardweedmanager.net>
Date: Mon, 25 Aug 2003

Was wondering if anyone knows what the common name is for Eulophia graminea.

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Date: Mon, 25 Aug 2003
From: <Ian.Millernt.gov.au>

When Eulophia graminea was first recorded in the NT, it did not seem to have a common name and at first it was called "eulophia". A common name that is used by some in the Northern Territory is "cheating orchid".

The logic in this is that many members of the family Orchidaceae are known for their beauty. "Cheating orchid" has a flower that is unattractive in comparison with most other orchids, and it is a weed. Hence "cheating orchid" is cheating on its family's good reputation.

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Date: Mon, 25 Aug 2003
From: Richard Denver <richardweedmanager.net>

Thanks Ian and Andrew. I decided to go with "Cheating orchid" as I have been advised that the first occurrence of this weed in Aus was in NT. If people are not happy they can always look up the Botanical name.


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