Weeds

Dealing with weeds is one of the routine maintenance tasks gardeners need to do to keep their landscapes looking good. This page will be a place to collect pictures of weeds common in Queensland gardens for easy identification.

News

Help Extinguish Dutchman's Pipe

Sunshine Coast Regional Council is calling on residents to look out for Dutchman’s pipe. It wants to contain the spread of this invasive vine and eventually eradicate it from the region. Council is currently working with land holders and managers to do just that, notably in the Upper Stanley, Pumicestone, Mooloolah, Maroochy and Mary River catchments. Meanwhile, if you spot the vine anywhere on the Sunshine Coast, the council is requesting that you report it. More information here: Have you seen a Dutchman’s pipe? (December 2020)

Chainsaw Through The Tulips

Fraser Coast Regional Council has declared war on the African tulip tree (Spathodea campanulata), aiming to eliminate the species from its parks and gardens entirely. As a first step, a number were recently removed from Margaret Lin Park in Kawungan. Going forward, staff will be recording the location of other specimens on Council land so that they can be scheduled for removal, too. Council says it will plant replacements of more appropriate species. As an incentive to residents, it's also offering a replacement for every African tulip tree removed from private yards in the region. Read more and learn how how to claim your replacement trees here: Pest trees to be removed from local parks (November 2020)

Tree Troubles

A decision has been made on the fate of four Himalayan ash (Fraxinus griffithii) trees in the centre of Boonah. As non-native species with weedy qualities, they were slated for removal as part of the town's ongoing revitalisation project, but community concern put plans on hold while Scenic Rim Regional Council reviewed the issue. Subsequently, Council announced it will retain three of the trees, necessitating some adjustments to the original landscape design. It will also install a trap which will help prevent the trees' many winged seeds (and other trash) reaching the creeks, but at a cost of $100,000 plus ongoing maintenance. Sources: Council to review trees in Boonah town centre and Council makes decision on Boonah High Street trees (September 2020)

Dingo link to weeds

Overgrazing is not the only cause of woody shrub invasion into semi-arid Australia, a new study finds. Comparison of habitats either side of the dingo fence in outback NSW showed a proliferation of woody species in the absence of dingoes. It's believed that foxes and feral cats reduce numbers of small mammals which eat the shrub seed, thus preventing its germination. Exclusion of dingoes removes a way of controlling these feral predators. Source: Detective work across dingo fence reveals new factor in woody shrub invasion (December 2016)

Steam Weeding the Cassowary Coast

Cassowary Coast Regional Council is introducing steam as a control measure for weeds in public areas. An advantage of the steam unit is that it can be used in all weather conditions, as well as reducing chemical use. It can also be used for killing mold on pathways and other cleaning. Source: Controlling Weeds with Steam on the Cassowary Coast (October 2016)

Weeds a window on origins of agriculture

Discovery of weeds typical of cultivated soils, along with cereal species and grinding tools at an ancient settlement on the shore of the Sea of Galilee now puts the date for the origins of agriculture to about 23,000 years ago , some 11,000 years earlier than previously thought. Source: International collaboration uncovers proof of earliest small-scale agricultural cultivation (July, 2015)

Weeds don't play fair

A study of Digitaria sanguinalis, the common weed of lawns and field commonly called "crabgrass", has shown that there's more to its success than simple competition. Chemicals from Digitaria caused changes in nearby soil microbes which reduced growth of test crops. The allelopathic chemicals could also directly affect other plants. Source: Crabgrass' secret: The despised weed makes herbicide to kill neighboring plants (June 2013)

New weed mat a model of recycling

Australia's CSIRO has developed a new weed mat from linseed straw. Besides its weed control properties, the mat is said to reduce evaporation from the soil while allowing rainfall penetration. It will eventually biodegrade completely, avoiding environmental pollution problems associated with synthetic weed matting. Developers believe that the process, involving high pressure water to mesh the fibres together, could also be used to manufacture matting from other agricultural by-products such as banana or hemp fibre. The fabrics created could potentially be put to other uses, too, such as shopping bags. Source: CSIRO sticks it to weeds this spring (October 2012)

New weed control developed in Qld

A new biocontrol agent developed by the University of Queensland could mean a simple and safe way to control woody weeds. Developed from fungi which already occur in the Australian environment, the treatment is delivered as a capsule inserted into the trunk of the tree. In addition to killing the inoculated tree, the fungi could persist to kill seedlings that subsequently emerge in the area, or even untreated mature trees nearby. Commercialisation of the "bioherbicide" for control of Parkinsonia is underway, but it has the potential to control many types of other woody weeds. More information at the University of Queensland website: Australia's first bioherbicide approaching release (August 2012)

Turn up the heat on weeds

Most of us have heard of using boiling water to kill weeds in paving, but studies at the University of Copenhagen have helped define how such heat treatments (flame, steam or boiling water) can be used most effectively. It was found that the leaves must collapse completely after each application, starving the roots. Also, the treatment must be repeated frequently enough to prevent recovery. Superficial or infrequent treatments permit regrowth and can actually promote grass weeds. With the right strategy, however, this low-toxicity method can eliminate even stubborn weeds. Source: Blanch your weeds (May 2012)