Waging the War on Weeds

March 27, 2014

In recognition of the 100-year anniversary of the College of Agriculture and Life Sciences Cooperative Extension, we are spotlighting a series of programs that UA employees, students and volunteers facilitate around the state.

Invasive and noxious weeds in Arizona are more than just pesky plants – they are downright destructive.

"We've got all the really nasty weeds in Arizona," said Larry Howery, noxious weeds/range management specialist with the UA College of Agriculture and Life Sciences Cooperative Extension. "Everybody should be concerned. The economic and ecological impacts are tremendous."

Howery said some non-native plants were introduced as ornamentals, like fountain grass and twisted barrel. Others – like buffelgrass – were introduced as food for livestock. Whether it is buffelgrass, camelthorn, toadflaxes, purple loosestrife, leafy spurge or another type of invader, these weeds threaten agriculture, wildlife and human health by ruining highways and making great fuel for wildfires.

To support weed abatement, Howery and a team of invasive plant experts from across the Western U.S. teach a short course in Southwestern noxious/invasive weeds to land managers from public and private agencies, including the Bureau of Land Management, the U.S. Forest Service and Arizona Game and Fish Department.

Over three days, participants learn plant identification and are given the tools to control weeds through herbicides, machinery and biological tactics, such as the introduction of different types of livestock and insects that consume weeds. Included in the course is a field trip through parts of New Mexico and Colorado.

"It's like trying to get the genie back in the bottle," Howery said. "It is expensive, and prevention is what we push in the short course. The easiest weed to manage is the one you don't have yet."

Kim Bennett, highway operations supervisor with the Arizona Department of Transportation in north Phoenix, said controlling invasive weeds costs his agency millions of dollars.

Bennett has attended the course three times to stay up to date on strategies. Left unchecked, weeds pose a safety threat to motorists by causing cracks and damage to the roadway and by blocking signs and guardrails.

"Cooperative Extension is a big help to so many of our communities – farmers and ranchers – in dealing with renegade weed populations," Bennett said. "Cooperative Extension does so much for Arizona, and what they are really good at is disseminating important information."

To learn more about Cooperative Extension programs, read: