New Invention Has Unsightly Tumbleweeds in a Whirl

It looks like a contraption straight out of a Stephen King novel--huge metal spokes whirling away, shredding everything in its path.

But the invention from New Mexico State University’s Advanced Manufacturing Center is out only to mow down the bane of the West--the ever-present tumbleweed.

The tumbleweed crumbler--an innovative combination of large, rotating metal spokes hooked onto the front of snowplow trucks--could make the thousands of unsightly tumbleweeds scattered across New Mexico’s highways much easier to handle.

State Department of Highway and Transportation workers brought the prototype machine to Albuquerque recently and plan to put it to work by the end of September. It’s expected to get frequent use in the fall and spring.

Early tests in Las Cruces, in which tumbleweeds were manually shoveled into the maw of the machine, proved successful. The machine ate the weeds up and spit them out.

“This may be a little graphic, but it looked like a bird flying into a fan,” said Steve Harris, who came up with the idea for the highway department.

When it comes to tumbleweeds, that’s exactly the idea.

The way things work now, a major windstorm normally forces crews of two or three workers each to go out in big trucks and stuff them with the gangly, sticker-filled tumbleweeds that scatter across retaining walls and barriers along the highways.

Tumbleweeds don’t weigh much, but they take up a lot of room. Once a truck is full, the weeds must be hauled to the city dump, cutting down the time that crews actually spend chopping weeds.

The process usually takes three to five days, involves eight to 10 workers and costs between $35,000 and $50,000 per year, Harris says.

“Whenever the problem gets too bad, you have a lot of people not doing what they should be doing,” Harris says. “We want to be out there fixing potholes and guardrails.

“Whenever tumbleweeds are out there, it gets frustrating for everyone.”

So the highway department offered a $40,000 contract to NMSU to find a solution. The university has spent $26,000 on the prototype so far. After the first road test, improvements will be made and flaws ironed out.

Then, Harris hopes, the machine will change the task of clearing the landscape for good. He estimates that what now takes five trucks five days to clear could be done by one truck in one day.

The machine is designed to move down the highway, skirting walls and barriers where the tumbling tumbleweeds accumulate. As the machine moves along, the horizontally whirling spokes from the shredder suck in the tumbleweeds and shred them on inner spokes that rotate vertically. The remains are funneled into a chute that spews them into the dump truck.

Ed Conley, a New Mexico State engineering professor whose students came up with the design, says the state has talked about buying four machines if they work.

Other Western states also are interested, and the machine could work for private industries that have tumbleweed problems, Conley says.

The project was born out of the highway department’s longtime relationship with the state’s universities and the scientific community. Harris says both have lost business because of the slowdown of work at the state’s science laboratories.

“We were trying to come up with more projects for them, but one of the main criticisms was that we weren’t coming up with something that would affect common people,” he says.

This will.

Almost everyone out West has seen 10-foot columns of unsightly tumbleweeds grown up on the sides of highways. And just about every driver in the West at one time has had to swerve to avoid an oncoming Russian thistle--the tumbleweed’s proper name--that can scratch up windshields and ruin paint jobs.

Harris says the prototype is nothing like the gadget he drew up on scratch paper the day the idea was first proposed.

The engineering students based their tumbleweed crumbler on combines and other farm equipment. They figured it would be sensible to use the snowplow trucks that already have hydraulic systems hooked up to run the plows.

“We did a lot of brainstorming and testing,” Conley says. “Finally, we came up with something that we hope will work. This isn’t perfect yet, but we think we’re pretty clear on what the basic design should be.”