Rancher Eddie Shumway had just brought hay to his Angus cattle when a cow collapsed to his right and another collapsed to his left.
They were both dead by the time he reached them. Alarmed, he sprang into action.
“I took my tractor and pushed my hay back into the stackyard and called the vet,” he said.
Shumway had thought he had poisoned his cows with the hay but the veterinarian recognized the signs.
“He was looking at the cows with the foam in their mouth and says this is not your hay,” Shumway said. “This is larkspur that did this.”
The pasture the cows were grazing in was full of the wildflower. Although, at the moment, the larkspur were just a tall shoot and had not yet flowered.
“They're usually the first green thing that comes up,” Shumway said. “And that's why the cows eat it.”
To protect the rest of his cattle, Shumway paid for weed and pest to spray the larkspur.
Deadly Beauty
Larkspur ranges in shades of blue, purple, pink, or white and is known for its tall, spiky flowers, with a distinctive backward-trailing spur on the flower.
The name "larkspur" comes from the quirky and eye-catching appearance of the flower. Its tall, claw-like blooms are said to resemble the long, sharp claws of a meadowlark.
They are also poisonous to humans and livestock.
“It's a pretty flower,” Hot Springs County Rancher Chip Axtell said. “But larkspur spreads with the native grasses and grazing pressure makes it worse.”
Axtell has areas on his ranch where the larkspur has unfortunately gotten established. He explained how it grows on the lee side of a hill, where it's moister and more shaded.
“It is lush,” he said. “Wherever the grass is pretty, you'd usually find larkspur.”
The larkspur comes up in the early spring and is one of the first things to grow when Wyoming will get moisture, which is part of the trouble for ranchers. It tends to grow faster than the grass and because it is the first thing that greens up, the cows will graze on it.
“The plants contain toxic alkaloids that are fatal to cows,” Hot Springs County District Supervisor Heath Love said.
The alkaloids, according to Axtell, are a muscle relaxant and results in paralysis in the cow. It causes their diaphragm to stop working and they suffocate to death.
Wyoming Weed and Pest has determined that two types of larkspur have had a detrimental impact in the Cowboy State and list them on the state noxious list. Geyer's larkspur, also known as plains larkspur or foothills larkspur, and the "dunce cap" or "tall larkspur" are both considered bad news to Wyoming’s cattle industry.
Although larkspur is still poisonous as long as it's green, it is at its most dangerous and deadly in the springtime when it is taller than the grass.
“If the cow gets grass and larkspur together, it's not deadly,” Axtell said. “If she gets a predominant amount of larkspur in her stomach more than grass, that's when the trouble is.”
He said that there's really nothing you can do besides keep them away from it in the springtime.
Cow losses can double when a poisoning from larkspur occurs. (Courtesy Chip Axtell) 
As the Axtell family move their cows on the open range, they are aware that some of the most beautiful wildflowers can be the most deadly to their cattle. (Courtesy Chip Axtell) 
As the Axtell family move their cows on the open range, they are aware that some of the most beautiful wildflowers can be the most deadly to their cattle. (Courtesy Chip Axtell) 
As spring approaches, ranchers in Wyoming are on the alert for the green shoots of larkspur. This beautiful wildflower is deadly to cattle. (Matt Lavin via Alamy)
Devastating Loss
Axtell has gone through the devastating loss of cattle to larkspur and said that it is hard to describe the heartbreaking scene.
One time he had just moved his herd away from a pasture so that a neighbor could come through with his cows. He put them into a pasture that had the wildflower, thinking that it was late enough in the season that the larkspur wouldn't be poisonous anymore. The next day, he came to move them and discovered that they had lost eight cows during the night.
“You just saw bodies lying along the creek banks,” he said. “That's pretty depressing to see that many cattle gone.”
A few others, still alive, had also been poisoned and he said that there was not much you can do at that point. It is best to not move them and hope that it works through their system.
“If there's a cow staggering as you're moving them out, you just let her fall back and don't try and move her any further,” he said.
Some people recommended cutting beneath the affected cow’s tail to bleed them. Axtell said he has tried that with mixed results.
Fighting The Noxious Wildflowers
The fight against the larkspur varies from ranch to ranch. In most areas, the ranchers just avoid the known pastures with larkspur or, if the area cannot be avoided, they will try to kill it off with broadleaf killer.
“If a landowner requested us to spray for larkspur, they pay for it,” Love said. “We give a 20% discount on chemical on plants that are on our list.”
In the past, Love said that Hot Springs County Weed and Pest have used Tordon, the brand name for herbicides containing picloram, often combined with 2,4-D, a common herbicide for broadleaf weeds, which is used for controlling woody plants and weeds.
It’s not an easy task.
“They've got some specialized chemicals, but you have to spot spray for it,” Axtell said. “You have to walk around and spray every plant, and then it is hard to kill because of the root structure. It can keep coming back, and so you have to retreat it.”
As the seasons change, ranchers are also aware of other dangerous flowers that Wyoming plays host to including hemlock and greasewood.
“Death camas seems to grow a lot in some years, and not very much in other years,” Axtell said. “It sends up one stalk with a flower on it and if cows pull up the root, one plant will kill a cow.”
As Wyoming ranchers prepare for the anticipated greening of spring, you can be sure they will be on the lookout for the beautiful larkspur and it won’t be to admire its beauty but to save the lives of their cattle.
Jackie Dorothy can be reached at jackie@cowboystatedaily.com.
