SAFFORD — It stretches across the American West and looms large in the Gila Watershed Partnership’s river restoration plans; the coyote willow (Salix exigua Nuttall).
The Gila Watershed Partnership is a nonprofit organization that strives to protect and improve the health of the Upper Gila Watershed, and one of their goals is replacing invasive plants like the tamarisk with native vegetation.
Coyote willow is a small, pliable tree found along riverbanks and other waters. Along the Gila River, invasive plants have largely pushed it aside. “Due to the density and extent of tamarisk, there are very few sites along the Gila River that still support coyote willow,” reads a memorandum of understanding for another of the partnership’s goals — working with local stakeholders to establish a linear river park.
“We are very interested in planting coyote willows. They are an important plant both ecologically and culturally,” said Gila Watershed Partnership Executive Director Melanie Tluczek. “ For river restoration, they are good at stabilizing river banks, can out-compete tamarisk, and are better wildlife habitat than tamarisk. They can also be planted from cuttings.
“Through our restoration, we are hoping to create large enough populations along the Gila River so that we can continue to use cuttings to benefit all the communities in the Upper Gila.
“Coyote willow not only grows really fast, which we need it to, but it’s a little more hardy than Gooding’s willow, our other species of willow out on the river.”
Tluczek said the willows were also good habitat for the Southwest willow flycatcher, an endangered bird. The flycatcher normally nests in willows, but has taken to the now dominant tamarisk in their place. Tluczek said another reason to plant coyote willow was to ensure the birds have a place to nest after the projected arrival of the tamarisk beetle.
“When the beetle arrives, we’re going to have a lot of dead tamarisk; the flycatcher will essentially come back to a barren landscape if we don’t have something else to replace it,” she said.
The partnership has planted coyote willows in places along the river, and is growing more at their Gila Native Plant Nursery. “I love producing willows because it’s a quick result and easy to grow,” said nursery manager Steve Plath. “You get a cutting to start and then eventually the plant branches. They produce a rhizomonous growth of the branch underground — a mat of themselves, which is great. That’s telling us they’re ready to go, they want to get in the ground.”
Plath said the coyote willow was also good at erosion control, but its value was overlooked in the early 20th Century in favor of another non-native, giant reed grass (Arundo donax) — which the partnership is also striving to reduce.
“I think by the time we were bringing in giant reed grass, we were already impacting the amount of water in rivers,” said Plath. “At the turn of the 20th Century, we were already losing habitat so willow colonies were actually dying back. Seeking a quick erosion control solution, they brought in giant reed grass from Southwest Asia.”
Plath said Arundo donax was not only invasive, but also less efficient at controlling erosion. “Willows will slow the water down, filter it and spread it out; giant reed grass just stops the water and breaks up into chunks.
“I don’t know if people then had the cognizance of the use of native plants per se. It’s been a long educational process societally, to truly realize their benefits. Now we’re coming to that realization. The light bulb didn’t go off for us until later, unfortunately.”