Willows are fast growing, deciduous trees of the genus Salix, that are mostly native to the temperate areas of the Northern hemisphere, growing in regions with moist soils, but are adaptable to almost any soil conditions.
The Weeping Willow (Salix babylonica) pictured above is one of the most recognisable willow trees worldwide. It’s quite unmistakable with its characteristic graceful, pendulous weeping branches, short trunk, broad rounded crown, and thin narrow leaves, often with paler undersides.
These incredibly useful trees are valued for their use as shade trees, for erosion control, timber production, and as a source of medicine. This article will detail all the possible uses in five broad categories, to provide plenty of ideas on how to make the most of this natural, renewable resource.
1. Source of Medicine
The use of willow bark dates back thousands of years, to the time of Hippocrates (400 BC) when patients were advised to chew on the bark to reduce fever and inflammation. Willow bark has been used throughout the centuries in China and Europe and continues to be used today for the treatment of pain (particularly low back pain and osteoarthritis), headache, and inflammatory conditions such as bursitis and tendinitis.
The bark of white willow contains salicin, which is a chemical similar to Aspirin (acetylsalicylic acid). It is thought to be responsible for the pain-relieving and anti-inflammatory effects of the herb. In fact, in the 1800s, salicin was used to develop aspirin. White willow appears to be slower than aspirin to bring pain relief, but its effects may last longer.
2. Source of Material for Construction and Manufacturing
Willow wood is used to make furniture, tool handles, wood veneers, and toys. It is used in wood turning as it is easily worked and is also used to make cricket bats.
Willows are a source of wicker for basketry (weaving of wicker baskets) and for making fish traps.
The wood of a willow can also be used as a source of fibre for making rope, string and paper.
Charcoal used by artists is exclusively made from the wood of willows. All charcoal is made by burning wood in the absence of oxygen, when wood is burnt in air it just becomes ash, which has completely different properties!
3. Source of Energy
Willow is grown for biomass, a renewable energy source which reduces the need for fossil fuels and petroleum products. Willow can be converted into a variety of sustainable environmentally friendly resources, including:
- heat and electricity by direct combustion, co-firing with coal, and gasification
- biodegradable plastics and other polymers
- biofuels
Willows are an ideal source of biomass because:
- Willows are easily propagated from unrooted cuttings.
- High yields can be obtained in a few years.
- Willow genetic diversity and short breeding cycle can be utilized to produce improved varieties.
- Willows vigorously re-sprout after each harvest.
- The amount of heat in a dry ton of willow is similar to other hardwoods.
Large scale projects to support willow as an energy crop are already at commercial scale in Sweden, and in other countries there are being developed through initiatives such as the Willow Biomass Project in the US and the Energy Coppice Project in the UK.
4. Ecological and Environmental Uses
Willows have many beneficial environmental uses, and are used in the following areas:
- Riparian buffers – Natural barriers that prevent chemicals from entering streams, ponds, and lakes.
- Phytoremediation – Willows clean up toxins from contaminated sites.
- Wastewater management (biofiltration) – Willows filter contaminants from wastewater and can be used in ecological wastewater treatment systems.
- Environmental protection and preservation – Willows are often used for land reclamation, streambank stabilisation (bioengineering), slope stabilisation, soil erosion control, shelterbelt and windbreak construction, soil building, and soil reclamation.
- Environmental reconstruction – Willows are used for constructing wetlands and wildlife habitat.
- Gardening – Willows are used for in the construction of hedges, ‘living fences’ and other living garden structures and general landscaping.
- Living snow fences – Strategically planted willows trap drifting snow.
- Farming – Willows can used by farmers as an animal forage to feed their stock.
5. Horticultural Uses
Willow bark contains natural plant growth hormones which can be used for rooting new cuttings. A home-made rooting hormone can easily be made from young yellow or green willow branches, see the article – Home Made Plant Rooting Hormone – Willow Water
Willow trees are very easy to propagate from any size cutting.
- A broken willow branch left in water will very quickly grow roots.
- Willows can successfully root from very thick pieces of stem as thick as a human thigh when put into damp ground. This method of willow propagation is known as taking ‘trunk cuttings’.
- Willow cuttings can even grow if put in the ground upside-down!
These trees are also very fast growing. Coppicing a willow (cutting it back to ground level) will result in numerous rods growing from the base that will grow at an amazing rate of 1.2 – 3.0m (4 – 10′) in a single season.
References
- University of Maryland Medical Centre, Medical Reference – Complementary Medicine – Willow Bark)
- College of Environmental Science and Forestry – The Willow Biomass Project)
I’m thinking of using some cut lengths to create some keyhole raised beds. Making the shape well above ground, letting them dry into the shape (so they don’t grow), then use some dried out cut as stakes to secure them down to the ground to add the compost. Once the UK welsh rain has calmed down of course.
Salix species including Salix alba; S. cinerea; S. chilensis; S. matsudana; S. viminalis, and all other species and hybrids except S. babylonica, S. x calodendron, and S. x reichardtii have been prioritised at a national level as Weeds of National Significance (WoNS).
A menace in australia if near rivers
Beautiful trees
Hi Fred, thanks for raising the point, much appreciated. Yes, that’s correct, some Australians consider willows to be problematic along waterways, and whenever I mention them in an article someone will inevitably point that out! 🙂
For the sake of perspective, I always like to remind people that their native plants are someone else’s weeds in another part of the world!
Often, many in their hurry to assert the dogma of the Australian nativist doctrine ‘Australian plants good, exotic plants bad’, which is a curious form of botanical apartheid (is this a thing in other parts of the world?), forget that trees are neither good nor bad, and don’t have moral agency. Willows are other people’s beloved native trees, much like eucalyptus trees are ours, and since this is an international website, we don’t use the subjective ‘weed’ term, whose attribution changes with geography and human culture, and therefore is not a reflection of the botanical attributes of the plant in question.
Since the internet is a global phenomenon, and is accessible worldwide, I sometimes wonder why references to eucalypts on Australian sites aren’t accompanied by ‘weeds of international significance’ warnings. Perhaps because every plant reference anywhere would probably require weed warnings for somewhere in the world and the whole concept would very quickly become completely unworkable and impractical!
In horticulture, we have an expression, ‘the right plant for the right place’, which not only emphasises using plants where they’re best adapted to grow, but also being responsible to not plant things where they will cause ecological problems. 🙂
What an amazing and diverse tree. Used to love them as a kid on our farm. Now I do realize they can be problematic to rivers in Australia, so would love to see an alternative native that is just as good. Not that I can plant one in a rental property, wonder how they do in pots, maybe as a bonsai?
Hi Linda, the argument that willows are a problem alongside Australian rivers and streams is debatable. The argument from governments and nativists is that unlike evergreen native plants, they drop their leaves into the water in autumn which changes the nutrient balance. This is hardly an argument in flowing water if we’re not running our streams, creeks and rivers dry by pulling out way too much water than is ecologically sustainable for commercial agriculture irrigation use. Considering that two-thirds of the food produced in Australia is exported, and the huge amounts of water required to grow produce in the wide, open windswept sun-beaten plains of industrial agriculture farms, effectively, the driest continent on the planet is exporting its most limited resource, water! The imminent collapse of the Murray Darling river system come to mind on this matter.
Other have pointed out that the root systems growing into the water create shelters for native fish and prevent erosion and collapse of riverbanks. The microclimates created by willows are more significant than those around many other trees. Willows have a much cooler temperature beneath their canopy due to evaporative cooling, they’re like nature’s air conditioners, and can support many other species of plants beneath and around them. They’re not like eucalyptus trees which suppress the growth or kill off other plants around them through the release of allelopathic chemicals or aggressive competition for water and nutrients. The willow trees provide ecological services, even in Australia when growing in riparian zones (the interface between land and a river or stream). A few years ago, the government threw a stack of money into removing willows from riverbanks, and all the contractors cashed in on the opportunity, ripping up all the willows they could find along waterways, creating massive ecological disruptions, and not replacing them with natives, which is tantamount to environmental vandalism. When money and emotions drive things, the planet rarely comes out better off! 🙁
There are quite a few Australian natives that grow along riverbanks and can tolerate wet boggy soils or withstand inundation for short periods when the river levels rise. There are Melaleuca, Callistemon, Casuarina, Elaeocarpus and Acacia species which can grow in these conditions, as well as particular species such as swamp banksia (Banksia robur), besides all the Eucalyptus species that occupy this ecological niche.
To answer your question, willow trees grow very well in large 45-50wide pots and stay fairly small and manageable. I have a weeping willow that is many years old growing in a 50cm wide plastic pot with a pot tray/dish underneath it to hold extra water. It’s only around 2m tall, looks very ornamental, and I use it to harvest the tips of the new branches to make plant cutting rooting hormone. They can be grown easily from a cutting placed in water, that’s how I grew mine! 🙂
How devasting about them ripping out the willows and causing more damage. So many wrong decisions made leaving a worse problem. Of course I did forget they hold the banks together. Now I know why there are hard to find, when we were kids they were everywhere (showing my age here lol). Thank you for the indepth article and reply comments, learning every day from you is fantastic. I will one day get a willow tree in a pot if I can find one, sounds great, what an amazing tree giving so much benefits.
Interesting article about many possibilities of use of this interesting tree.