Kansas farmers and ranchers are battling noxious plants. Some can kill cattle, others are strangling crops.

Alice Mannette
Topeka Capital-Journal
John Wimer, a noxious weed specialist in Kingman County, talks about noxious weeds Saturday at the Kansas State Fair. Behind him is pictured the root system from one bindweed seed.

The Kansas prairie is dotted with many invasive grasses.

Some were brought over during the 1800s. Others were integrated after the Dust Bowl. A few came in to beautify suburban landscapes, and one or two others are native to the landscape.

But whether they came from the Caucus Mountains in Russia or fields in North Carolina, invasive weeds are wreaking havoc on Kansas pastures and cropland. Most of the grasses and weeds are difficult to eliminate, and cattle, goats and sheep often turn their noses up at them.

Some weeds and grasses can kill animals or smother crops. Researchers are trying to find ways to obliterate the noxious weeds.

More:State Fair entry triggers federal inquiry into how invasive species made its way to Kansas

"The worst is old world bluestems (Caucasian and yellow bluestems)," said Walter Fick, Ph.D., an extension range management specialist and professor at Kansas State University. "Silver bluestem seems to be increasing in western Kansas."

Many are difficult to control. Fick recommends wiping an herbicide on them. But because they are a perennial and grow from established root systems, eradicating them is difficult. Yellow bluestem and Caucasian bluestem are found throughout Kansas, appearing in more than 90 counties. 

"You can use an herbicide that at a low rate can selectively control our Old World bluestem and allow our native grasses to survive," Fick said. "It might stun them (native grasses) a little, but they seem to come back."

These 14 noxious weeds can be found in Kansas.

More:Invasive grass turn prairie into wasteland. Here's what to do with Old World bluestem.

Noxious weeds grown by Brad Friesen, a noxious weed specialist from Meade County, are on display on at the Kansas State Fair.

Sericea Lespedeza

A perennial that flowers from July to October. Halfway through the growing season, tannin collects in the plant and it becomes undigestible for cattle. The plant was brought over from Asia in 1896. It was on the Conservation Reserve Program list in the 1980s as it is hardy and resistant to drought. One plant can spread more than 1,000 seeds, which are viable for 30 years. 


This grass entered the U.S. in 1830, traveling over from Turkey, and now resides throughout the state. Although it has some nutritional content, it is toxic to livestock when there is drought or frost during the growing season.

"Animals will die from it," said John Wimer, a noxious weed director in Kingman County.

Field Bindweed

This plant's root system can grow 30 feet deep. Introduced during the 1870s, this European weed not only hogs the water but also causes stress on hogs who try to eat it. This vine weed will wrap around other plants. In 1937, it was the first weed to be declared noxious in Kansas.

This Musk Thistle was grown by Brad Friesen, a noxious weed specialist from Meade County.

Musk Thistle

Musk thistle headed over to the East Coast of the U.S. throughout the mid-19th century. By 1932, it reached Kansas.

"It will take over farm or pastureland completely," Wimer said. "We've seen thistles so thick you can't even walk through them, let alone the cattle walk through."

Hoary Cress

This plant, which originally came from Eurasia, contains an element that causes irritation to mucous membranes.


Kudzu can grow up to 100 feet tall when climbing trees and other structures, but otherwise, the perennial legume blankets the ground. It often grows over native grasses, smothering them in its wake. It can crush trees. It is prevalent in southeastern Kansas.  It was brought over to the U.S. from Asia in 1876.

Canada Thistle

This thistle, which came to the U.S. during the 1700s, builds up toxic levels of nitrates. It is prevalent around the Topeka area.

Bur Ragweed

This native plant, which inhabits western Kansas, is unpalatable and spreads quickly, choking desirable plants. 

Russian Knapweed

Russian Knapweed infests alfalfa and grain fields. Cattle won't eat it, and it will cause a chewing disorder in horses. 

Leafy Spurge

This plant was brought into the U.S. in the early 1800s. It is aggressive, spreads quickly and can crowd out other vegetation.


This aggressive grass, which reduces productivity in crop and prairieland, was introduced from the Mediterranean. 


Otherwise known as hog potato, this plant is native to southwest Kansas. According to Missouri State University, this plant can be toxic to livestock, but usually the livestock ignore it.

Bull Thistle

The leaves are covered with rough spines.

Multiflora Rose

This grass is native to Japan and was introduced to the U.S. in 1855. It is used as roost stock for ornamental roses, a cover crop, a highway barrier and a living fence. Unfortunately, this pant has spread aggressively into pasture and cropland.

"Certain plants do better on certain soils," said Roy Bushek, a noxious weed specialist in Kearny County.

These grasses are difficult to control as farm equipment inadvertently spread their seeds.

"Deer and birds can spread these plants," said Brad Friesen, extension range management specialist for Meade County. "When cultivation came, they started to spread."

Each county has a noxious weed specialist who farmers and ranchers can call for advice to control these invasive species. Sometimes farmers and ranchers want to control other grasses, like sandburs, which have stickers, that are on the annoyance list but haven't made it to noxious.

"Sandbur want to be noxious, but it's not," Friesen said. "It's obnoxious."

Noxious weed information is from the Southeast Kansas Weed Management Area, the Weed Directors Association of Kansas and Kansas noxious weed specialists.