Allnutt Park — outbreak of water mould

Published on 25 February 2019

Council officers have recently observed the presence of a water mould (Phytophthora) amongst the trees and soil at Allnutt Park. It is important to note that, whilst this is an issue for the health of trees within this park, it will not affect the use of Allnutt Park by the community for social gatherings, play or exercising.

You can help avoid spreading this water mould by:

  • cleaning your shoes of soil after leaving the park;
  • staying on the pathways;
  • avoiding wet soil areas; and
  • brushing down your pets after exercising. 

What is Phytophthora Cactorum (water mould)?

Phytophthora Cactorum is a water mould, which thrives in moist warm soil and has the ability to infest a wide number of trees and plants affecting the vascular tissues causing the plant to wilt and die.

How is Phytophthora Cactorum (water mould) spread?

The spread of this water mould is primarily through a single cell spore with tail or whip that allows it to travel through water and attack trees. The most common way this fungus is spread, is by the movement of soil. Most commonly by small amounts of soil on the soles of shoes, animal paws or even bicycle tyres.

What is Council doing?

Allnutt Park is a popular place for children to play, adults and animals to recreate. The use of potent fungicides in our parks where they could cause harm to the public is not a method of treatment Council would consider.

Council is undertaking a more natural approach that will deliver the same results, over a slightly longer period.

We have mulched some of the trees with a very thick layers of Bush Mulch, up to 30 centimetres deep. This will provide a food source for cultures of beneficial bacteria and fungi that we plan to add (these are not harmful to humans and animals and are found naturally in good soil — these are the good people). By growing these cultures, it will:

  • improve the soil around the trees
  • improve the tree health
  • in some cases, attack the pathogen directly
  • compete with or displace the pathogen.

The current plant health care program is an intense regime of improving the soil condition in the park under the target trees over the next three years. To ensure we are doing the right thing regular soil and plant testing will be undertaken and the program will be adjusted accordingly before we broaden the program out to include the whole Park.

Science tells us that healthy organic and nutrient rich soils that are well drained will control the spread of Phytophthora, as these are not the ideal growing conditions for the pathogen. It is unlikely that we will totally eradicate the pathogen as Phytophthora is present almost everywhere in the urban environment. What we will do is create an environment where it is difficult for the fungus to thrive.

Stopping the spread of Phytophthora Cactorum (water mould)

Staff entering the park and undertaking their normal duties will be using a plant hygiene protocol to ensure they do not spread it to other parks. This ensures no soil is removed from the park accidently whether on their tools, vehicles or boots as they will be treated with a spray. (Whilst this spray is of low toxicity it will not be made available for public foot washes, out of concerns for safety of children and animals — residents can use bleach for a similar effect).

Will the park be closed?

Council is not closing the Park while we undertake these works — we love people in our parks exercising and recreating, children using the playground and hosting small parties. We want all of these activities to continue. Council made the decision to relocate its upcoming Party in the Park  due to the popularity of the event and the number of people that attend.

For further information, please contact Council’s Parks Services on 9524 3323 or email