The name “giant reed” conjures up images of a monster from a 1950s science fiction thriller.
Also known as giant cane, this invasive species, known scientifically as Arundo donax, has become a common sight in the Moab Valley. Though giant reed won’t be eating your dogs and menacing the streets, this non-native weed can cause ecological damage to fragile desert habitats and riparian areas if left unchecked.
“We have more of it in this valley than anything that has been documented in the rest of Utah,” said Grand County Weed Supervisor Tim Higgs, who has been removing non-native plant species with Grand County for 28 years this month. “There are over 100 (giant reed infestations) in the valley, and we haven’t even documented every one of them.”
Grand County is set to receive a $66,300 grant from the Utah Department of Agriculture and Food (UDAF) to control infestations of giant reed and other noxious weeds in the area.
Giant reed was first introduced in California by colonists in the 18th century to stabilize canals.
Utah State University Extension Weed Specialist Corey Ransom said the Eurasian native grows between 6 to 30 feet tall and has dense clusters of cream to purplish-brown flowers that form plume-like tufts that can be 1 to 2 feet long. Many homeowners are attracted to the height of the giant reed, recognizing its potential as a privacy barrier.
Giant reed grows at an aggressive pace and is detrimental to local ecosystems.
“Data show that the giant reed can use upwards of three times the amount of water compared to native species,” Ransom said. “(It can) cause sediment retention and change flood water patterns. They lack the species diversity and complexity found in native ecosystems.”
“These plants impact human and wildlife use in the valley and in the river corridors,” said Kara Dohrenwend, owner of Wildland Scapes, a local nursery where individuals can learn about and purchase native plants.
Giant reed thrives in arid, warm climates.
“They create ladder fuel situations which carry fires farther and limit visibility in and out of the stream corridors, which can be a safety concern,” Dohrenwend said.
The grant comes at the perfect time for the county: when the problem is daunting, but there is still time enough to solve it. Higgs said that the work will cover a lot more ground than what is in Moab.
“It will include Dolores, Thompson, Castle Valley and Colorado (River),” he said.
Ever since the UDAF declared the giant reed a noxious weed three years ago, Higgs has worked with his team to remove the plant by mechanical and chemical means.
“We spray and control weeds on county property which includes bike paths, county roads, and the old highway north and south of Interstate 70,” Higgs said.
When it comes to the giant reed and other invasive species that grow on private property, the removal process requires a great deal of communication between Higgs and individual landowners.
“We notify landowners of noxious weeds growing on their land and try to work with them instead of giving the individual a ‘notice to control (the giant reed problem on their land),’” he said.
If the Grand County Council declares a giant reed thicket a “public nuisance,” the Grand County Weed Department can take control of the situation and remove it.
“No one likes to have legal documents handed to them,” Higgs said. “It is much easier to work with people than to fight them on things.”
Higgs and his team at the Grand County Weed Department hope to educate the public about the removal and replacement of giant reed with non-noxious plants.
The UDAF grant requires matching funds in the form of work hours spent by landowners to remove weeds on their property. The work is not easy.
“You can use a chainsaw to remove the tops, then you spray herbicide, then you remove the roots,” Higgs said. “You have to remove the roots completely, which are about 6 inches thick.”
With regenerative capabilities not unlike that of a starfish, the giant reed can re-sprout from individual root and stem parts.
“Even small root or rhizome fragments can sprout and form new plants,” Ransom said.
“The work is mostly mechanical and takes about two to three years to completely get rid of it,” Higgs added. “You have to be diligent.”
Landowner participation makes Higgs’ job much easier.
“If we can get everybody involved, if people are willing to help us work with this, we could have every giant reed eliminated within four to five years and incorporate replacement plants that provide people a screen to give homeowners privacy,” he said.
Estimating that there are around 130 private properties in the county that contain giant reed groupings, Higgs said he wants to help “at least 28 property owners on this grant and hopefully assist the same amount next year.”
Grant funding will also fund one seasonal employee, herbicide, a rented excavator and small tools like Pulaskis, as well as replacement plants.
“Homeowners will get up to $125 in plant vouchers if they want native plants to plant instead of the giant reed,” Higgs said.
Dohrenwend is one of the only vendors of native plants in Grand County and provides sage advice to help landowners find replacement plants to best suit their needs.
“There are a lot of native plants like New Mexico privet and three-leaf sumac that can give the same screening with less fire danger and more benefit to birds than Arundo provides,” Dohrenwend said. “Plus, they are prettier.”
If you notice giant reeds on your property, you should call Higgs immediately to notify him of the threat to native ecosystems. You will probably need to leave a message, as he is normally working out in the field.
“People are always saying they can’t get a hold of me, but how can I get rid of noxious weeds sitting at a desk?” he said.
You can find out if you have giant reeds and other noxious weeds growing on your property by visiting www.eddmaps.org and looking at various distribution lists categorized by plant. Homeowners can remove non-native species like the giant reed and Russian knapweed themselves by hand and by spraying approved herbicides.
“Always follow instructions on the label,” Higgs said.
People should care about weed infestations, he added.
“Whatever is on your property is not going to stay on your property,” he said. “Weeds move and don’t care about boundaries. Your problem could become your neighbor’s problem if you don’t do something.”