The Crucial Roles of Willows in Sustainable River Management

This post really requires a drum role or fanfare.

With permission, I am posting a scanned copy of ‘The Crucial Role of Willows in Sustainable River Management’, by Professor Haikai Tane. I will also lodge this in our useful publications page.

Click on the image below to download the PDF.

CRW 1_2

This is an excellent resource for anyone seeking to explore the reality of willows within an ecological-thinking perspective (as opposed to a reductively-compartmentalised nativist one). The research presented is mainly based on a New Zealand environmental context, but there are obvious parallels with the Australian situation. There is ample food for thought for Landcarers here.

I, for one, am very grateful that Prof. Tane has allowed this to be shared with us. I’m sure any feedback or discussion would be welcome.

Commercial copyright restrictions apply, as outlined on the second page. Any inquiries regarding further use or reproduction should be directed via the contact details listed there.

As an introduction, I provide the document’s summary (pg. 5) here:

Grievously misunderstood in NZ today, willows may well be the world’s most widely propagated and planted tree in temperate climes, for managing wetlands, stabilising streams and restoring the environmental health of riparian zones. Viewed from the broad perspective of socio-economic and ecological benefits, willows are without a doubt New Zealand’s most important riparian trees.

For more than 100 years willows have been propagated, planted and encouraged to naturalise in New Zealand for their pollen, nectar, shade, shelter, timber, stock fodder in droughts, clean burning firewood, willow canes, medicinal charcoal and floral materials. Willows provide wildlife habitats that have proven ideal for traditional fishing and fowling activities commonly practised among indigenous Pacific peoples. Willow is also the most widely used plant material for conservation of stream, river and lakes and protection of road and rail infrastructure. In New Zealand’s riparian zones where agriculture and apiculture are intricately linked, willows are also indispensable for sustainable farming, because New Zealand farming requires very large populations of honeybees to ensure productive farm pastures and pollination of seed crops, berry bushes vines and tree crops. In most parts of rural New Zealand, willows are the main and most reliable source of spring pollen and nectar to build up populations of honeybees. Without doubt, willows are integral part of the natural and cultural heritage of rural New Zealanders nearly everywhere they live.

Willow removal programs disrupt and undermine ecological processes in critical riparian zones. Willows are fundamental in controlling aquifer systems and removing them threatens the stability stream banks and beds. Removing willows can generate slugs of nutrient and sediments, which then trigger algae explosions with toxic residues. Because poisons sprayed to kill unwanted plants and prevent willow regrowth are toxic to in-stream macro-invertebrates, they kill algae eating biota. With willow removal programs, stream ecosystems receive a triple whammy: algae explosions from accelerated sediment and nutrient discharges; severe damage to riparian ecostructures, which control aquifer and springs, and; systemic poisoning of riparian biota. The result is a rapid decline in stream health, stream flows and the quality of water.

8 responses to “The Crucial Roles of Willows in Sustainable River Management

  1. Congratulations to the founders of NNLC! Being an ‘exotic’ trees fan, I couldn’t agree more about their usefulness in our local temperate climate. Maybe the initial trigger for nativism was anti-colonialism – a desire to escape cultural cringe and be ‘truly Australian’. If so its time to confront the contradictions and grow up. Lets have some multicultural ecology.
    My especial interest in willows is their broader use – as living fences and structures. So Peter Marshall’s comments are very pertinent especially about the loss of bushcraft culture. I’d appreciate being contacted by anyone with willow-building skills.

    • You’re absolutely right Gill. A big part of throwing off the cultural cringe was a passionate embrace of all things Australian and NOT English, NOT foreign! Interesting that you should raise this point on this day of all days.

      It’s a pervasive theme in conversation with nativists that early settlers weren’t REAL Australians because they didn’t love ‘our’ native species. Nationalism goes hand in hand with nativism. Many people of a certain generation are stuck in their heads still fighting battles against a conservative 1950’s ‘British’ Australia. For them, real Australians must reject everything to do with ‘the old country’, including species not present in pre-European times. Once people decide that everything foreign is bad, they feel good and certain; everything is simple and we can just move on to the most efficient method of eradication.

      On willows, when we visited England Annie and I noticed lots of building with willows around the place, mainly arbours and other garden structures. Even in the middle of London (Princess Diana adventure playground). Good to see these traditions still alive. In the midlands we also saw some great woven hedge work for farm fences. They had hawthorn as a framework, but were full of other volunteer species. Imagine a completely biological farm landscape! Don’t try this at home Australians, it’s barbed-wire for you!

  2. For great fun have a look on Google –
    -Willow Work Architecture .
    -Cassagrande Laboratory Sandworm
    -Osier Vivant
    -Basket making of Californian and South West Indian tribes .

    Incidentally , Australian soldiers on the Western Front wove hundreds of miles of trench revetements out of French osier .
    They brought home cuttings which are now hundred year old trees .
    I’d feel a bit sick poisoning such a heritage , personally .
    To me they are as special a link with our forebears as is the Lone Pine .


  3. I should mention, there is the potential for an Australian version of this excellent publication to be produced in future. An amount of research material is already available. Anyone with an interest in sustainable river management who is in a position to support production and publication of this much-needed educational resource can get in touch via icare (@) or contact Prof. Tane direct.

    • Thanks for this David. Another great example of the extensive benefits of salix. There is extensive literature regarding their use for phytoremediation of various industrial pollutants in Europe. Populus (the poplars) are another extremely effective species for this. Here in Australia I’ve seen examples of where willows help to moderate the high energy levels (flow velocity) in urban run-off too; especially where urban storm water drains enter rural watercourses. Cheers, Ben

  4. Very informative article. Thanks for sharing as an important information about the importance of willows. They are really an important part of our ecosystem that must be preserved.

  5. Meat and Livestock Australia were speaking on Radio National today about a rare red algae which can be used as a feed supplement to reduce ruminant animals methane emissions .

    An excellent aim , but an expensive way of achieving it .
    Willow fodder contains condensed tannins too .
    Instead of diesel intensive marine gathering and transport farmers could be growing the feed supplement onsite , in every paddock .
    With added benefits of shade , shelter and nutrient cycling .

    The pity of it . Salix have been so demonised that this simple technique is politically incorrect to discuss .



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