Why is Willow Eradication Necessary?

NECMA have removed willows from the King River below Whitfield, the Ovens River at Oxley Plains, the Ovens River at Bright and from the Fifteem Mile Creek. They have also been removed from the river at Corryong.

In all cases, local residents cannot find any benefit from their removal. In all cases, the alarm bells are ringing.

Whilst NECMA Policy document Willow Management Strategy for the North East Catchment Management Authority sees willows as 'feral' with procedures for willow removal, Kurt Cremer, Forest Scientist with the CSIRO, suggests in a paper titled, "Remove Willows to conserve Water?", that "Removal of willows can degrade water quality, if removal of the shade increases the water's temperature and light and if this boosts the development of blue-green algae. Also, willow removal causes erosion. Because willows absorb water from the stream itself, they probably also absorb nutrients from the water and transfer some of these via leaf shed to the soil. Removal of willows could thus contribute to eutrophication."

In the CSIRO publication, Problem Willows, Mr Cremer coins the term 'Feral willows' and suggests that radical removal should be avoided. He suggests,"Proper management is still possible and in the community’s interest. Total eradication of all willows is not desirable. So, don’t Rambo. Resist instant gratification from big machines that clear live willows from wet places, but plant multitudes of broken branches. Don’t leave banks unprotected. Don’t denude the landscape unnecessarily. Don’t just spend large sums on control and, by neglecting to take note of why willows spread, ensure the job never ends."

But that is not what we are seeing and is beyond NECMA Policy recommendations. As an example, the policy states,"Mechanical removal from streams of willows that have not been killed first is rarely justifiable, because it often does more harm than good by propagating the willows from broken live branches taking root at and downstream of the site.

Take a walk along any of the works and you will find live willow debris in and out of the water. These willows were not chemically poisoned before removal as required by the NECMA policy.

A perusal of the policy shows that the in-river excavation of the banks at Gentle Annie Bridge was not called for and the denuding of the banks of the Ovens - as seen in the photo above - was not called for. The policy offers a variety of management concepts that have not been used.

The state government of Victoria (1997) prepared a detailed report titled “Willows on Victorian Waterways: Towards a willow management policy”. This document provided four key recommendations to government and the river management industry: 1. Raise awareness about willows. 2. Reduce willow plantings. 3. Manage existing willows. 4. Undertake research to fill knowledge gaps and provide additional information.

NECMA have ignored these recommendations and seem intent on eradication.

Let's compare the photo and the NECMA Policy. It must be assumed that the bare earth in the photo was completely infested exclusively with Crack and/or Black Willow - the offending species named in the Policy.

The NECMA Management Policy states:

"Where willows have little chance to spread, manage them like any other tree, but keep out the most aggressive species, and look for seedlings. Similarly, Crack Willow (male) more than 20 m from a stream and more than 2000 m from a compatible female is quite safe.

This infestation was contained within the pine tress on one side of the river and gum trees on the other with little chance of spread. The photo shows that removal works extend way beyond '20 m from a stream'. It must therefore be concluded that the works were excessive.

The NECMA Management Policy also states:

"The control of willows on mobile sediment and gravel bars shall wherever possible and practical be undertaken using chemical control."

- and in relation to outside bends,

"Willow has been planted in the past on the outside bends, to reduce the rate of meander movement. Often the removal of willows at these sites will exacerbate erosion, and cause further in-stream issues such as excessive erosion, and sedimentation."

Without effective stabilisation, this outside bend will be washed away to form the biggest fishing hole on the Ovens River - big enough to provide irrigation requirements for the golf club.

I believe the NECMA Policy is flawed and is being misinterpreted. The NECMA policy is based on the destructive side of CSIRO documentation. It does not include the balancing warnings that CSIRO have made.

According to the ABC Australian Story, "Of Droughts and Flooding Rains", the CSIRO now supports Peter Andrews' methods of slowing down the flow of water in rivers/streams including the planting of willows converting degraded, salt ravaged properties into fertile, drought-resistant pastures.

Surely, it is time for NECMA to work with the community, as their policy demands, rather than deciding what is best for us.