Soaking Willow Cuttings Helps
Them Protect Streambanks
By Hank Becker
September 27, 2000
Soaking willow cuttings gives them a head start in protecting eroding stream
Channel erosion is a serious problem in many areas. For years, researchers
have tried to stabilize streambanks with planted vegetation. This technique is
usually cheaper, better for the environment and more aesthetically pleasing
than artificial structures made from concrete and stone.
For four years, Agricultural Research
Service hydraulic engineer Doug Shields at the
Laboratory, Oxford, Miss., and University
of Memphis wetland plant physiologist Reza Pezeshki investigated willow
cuttings survival or effectiveness when planted along streambanks to
Planting willow cuttings 3 to 8 inches in diameter and 4 to 8 feet long in
winter when they are dormant is an attractive option for rapidly eroding sites.
The posts hold and stabilize the bank until the young trees become established.
Then the willows create conditions favorable for natural establishment of
native vegetation. However, in many cases, willow posts planted in streambanks
have died within a year.
To find ways to enhance willow survival and growth, the scientists conducted
a series of field and greenhouse studies that showed that cuttings are very
sensitive to moisture and soil type. Theyre currently developing a simple
site evaluation protocol to assist streambank restoration planners in deciding
where to plant willow posts. Site characteristics used in the protocol will
include typical groundwater elevations and soil type.
Recent greenhouse studies have shown that survival rates can be doubled by
soaking cuttings for 10 days before planting. Soaked cuttings outperformed
those planted immediately after they were cut, growing higher and producing
more biomass and greater numbers of roots.
This finding will be of great interest to all who are working to create
forested riparian buffer strips, control streambank erosion and restore the
nations 3.5 million miles of rivers currently considered degraded by
erosion, sedimentation and excess nutrients.
ARS is the chief research agency of the U.S.
Department of Agriculture.
Scientific contact: F.
Douglas Shields, Jr., ARS National Sedimentation Laboratory, Oxford, Miss.;
phone (662) 232-2919, fax (662) 232-2915,