Riparian plants are floated down to the restoration site.
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How To Construct Willow Weavings                                                                                                              

Technical information about how to construct willow weavings:

Willow weavings have become an integral part in our quest to repair eroding stream banks. Willow weavings – a name we coined to describe a method of armoring actively eroding stream banks with 100% live willow poles – have proven to be successful in holding together raw, vertical banks that otherwise are difficult if not impossible to plant even with large containerized shrubs and trees or willow poles.

Willow weavings allow for inexpensive custom-made structures made from locally harvested willows to fit specific sites without using fence posts, cable, entire trees, concrete, car bodies and riprap. A huge advantage of using willows is that if they wash out they will decompose or perhaps take root elsewhere like beaver cuttings often do – not leaving unsightly and hazardous debris in and along the water.

Even a relatively small willow weaving utilizes hundreds of willow poles – full length and untrimmed.  The poles are laid horizontally and packed tightly on the stream bank and held together by willow poles jammed into the bank from the top and bottom of the structure. The willow weaving method allows for just about every willow pole to root in the mud whether “planted” vertically or horizontally. Roots from willows and other native riparian woody plants grow deeply and branch out to hold together and stabilize stream banks.

There is no exact science to restoring native riparian areas – each river and creek is unique and responds in its own way to restoration methods. We have learned from trial and error which methods work best including willow weavings. We followed some basic guidelines about planting including using dormant untrimmed willow poles.

The concept is simple: willow poles held in place in mud are likely to root out and grow.  We used water jet stingers to make deep holes in which to plant willow poles to securely hold other willows – horizontally placed and packed tightly - in place to prevent them from washing out during spring run off and other high water events.

Darin Zarbnisky, who initiated our willow weaving projects in April 2005 along Round Valley Creek, took advantage of a slightly overhanging bank and a chunk of the bank that had fallen into the creek to use to anchor the willow poles.

Also see the Interactive Panorama of this willow weaving on Round Valley Creek, 4/05.

 Borah High School students use a water jet stinger to plant willow poles along the Little Salmon River.
Volunteers jam willow poles into the top of the stream bank while volunteers below guide them over, under and through the willows packed against the actively eroding bank to secure the willow weaving which armors the bank from further erosion. April 14, 2005.

We built our next willow weaving along Fourmile Creek in May 2006.


IDFG Michael Young and volunteer Fred Confer build a willow weaving to armor an actively eroding bank on Four Mile Creek, 4/06. Photo © Kirsten Severud, 2006
Looking down on the Four Mile Creek willow weaving after construction, 5/06.
In this radically calved bank we planted the large end of each willow pole into the mud by hand on both the right and left edges of the structure. We continued to plant the large end of poles throughout the structure and then twisted and wove everything together.  We wrapped poles around the bundles and “staked” the stream edge vertically and the top horizontally with poles using the water jet stingers to make deep holes in which to insert willow poles.  
The willow weaving four months later alive and effectively armoring the raw bank. 8/06
Along another stretch of Fourmile Creek we built a willow weaving in mid May 2006. We planted each willow pole end under the cut bank and then staked it with other willow poles from the top of the bank and put some poles vertically into the stream bottom.
Willow weaving under construction along an actively eroding bank on Four Mile Creek, May 2006.
The willow weaving flourished in spite of a high water event that occurred a few days after the construction. High, fast floodwaters moved the creek channel dramatically and moved rocks, cobble and gravel into piles creating new gravel bars including one in front of the willow weaving. 8/31/06
Our successes on the tributaries of the Little Salmon River motivated us to try our hand at protecting over one hundred yards of vertical raw and actively eroding bank on the river. We knew we had our work cut out for us and that the Little Salmon River can be in flood stage for two months during spring run off from melting snow in nearby mountains.
Heavy snow pack in the mountains combined with spring rainfall resulted in flooding over the banks of the Little Salmon River during the prolonged run off in April and May 2006. 4/06
Taken downstream from the photograph to the left on the same day, this picture shows the confluence of Round Valley Creek with the Little Salmon - well under water. 4/06

We had planted dozens of one and two gallon containerized native shrubs and trees along a bend that all fell into the river during the 2006 spring run off along with large chunks of real estate up to twelve feet back from what had been the edge of the bank when we planted in June 2005.

We waited until late September 2006 - when the water level was low and when the willows had begun to go dormant, as evidenced by their yellow leaves - to build the willow weaving along the Little Salmon River. The images in the Photo Gallery and on the right show volunteers constructing two massive willow weavings on two banks, each over 200 feet long on opposite sides of the river.

We planted thousands of locally harvested willow poles into the cut banks, staking the poles vertically into the stream bottom and horizontally against the bank. We twisted the vertical and horizontal poles together and wove them into the mass willow structure to secure it. 

We tried to make the weaving fit the stream direction by placing most of the large ends upstream to be able to handle the large runoff that the river experiences.  We also added extra willows for bulk without staking them directly into the ground and to make sure we had some poles underneath the structure that were in complete contact with the soil the entire length to provide mass rooting potential. 

Water jet stingers enabled us to plant poles several feet deep.  We have not built willow weavings without water jet stingers but think it would be possible on small creeks. The stingers allow us to secure poles in difficult substrate and to construct large willow weavings along rivers.

Constructing willow weavings doesn’t require an engineering degree – just a heck of a lot of willows and volunteers willing to work creatively in the mud!

Also see the Interactive Panoramas for these willow weavings on the Little Salmon River at Site 1 and Site 2.

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