LANCASTER, Pa. — Canada thistles are a thorny issue for many farmers, in more ways than one. That’s especially true if those thistles are located on land enrolled in the federal government’s Conservation Reserve Enhancement Program, or CREP.

Few would argue with CREP’s goals of improving water quality, fostering wildlife habitat and establishing riparian buffers. However, as many CREP participants — and their neighbors — have learned through the years, controlling noxious weeds can be one of the hardest parts of the CREP equation.

Beef farmer Ted Barbour, in Lycoming County, Pennsylvania, raises grass-fed Herefords, Red Angus and black baldies, which he grazes on 55 owned acres and another 15 leased acres. Barbour typically has 20 cow-calf pairs that he retains to finish, direct marketing 22 to 23 carcasses per year.

As an engineer who returned to the Cogan Station farm where he grew up, Barbour works full time away from the farm. His goal for his cattle operation is to make the farm sustainable for his family to reside there.

Barbour has had 8 acres of his property enrolled in CREP’s Conservation Practice 22 (CP-22) riparian buffer acreage since 2005. Fortunately, he doesn’t have a noxious weed problem on his own CREP land, but Canada thistles were spreading to Barbour’s pastures from the CREP acreage of two neighboring farms, both enrolled in CREP’s CP-1 perennial grasslands practice.

CREP regulations typically limit the ability to mow enrolled acreage and do not permit grazing. Most participating property owners thus end up using herbicides to fight thistles and other noxious weeds. But Barbour took a different approach to Canada thistles, and recently spoke about it at the Pennsylvania Association for Sustainable Agriculture (PASA) annual conference held in Lancaster in February.

While Barbour is not a certified organic farmer, he bills his cattle as “all natural, no grain,” grass-fed beef. In keeping with that philosophy, he said, “I’m all about eliminating chemicals.”

It’s not just the expense of herbicides that he worries about, but also the environmental harm and the wholesomeness of his finished product. Barbour also points out that herbicides like the glyphosate, dicamba, 2-4-D and triclopyr commonly used to combat Canada thistle, kill desirable plants, too, counterproductively setting the stage for invasive species to establish themselves.

Barbour explained that he had attended an out-of-state grazing conference about a decade ago, where he first learned about emergency, routine and prescribed grazing options for CREP land, each with their distinct requirements and necessary special approvals. Navigating the alphabet soup of multiple partners like USDA, NRCS and FSA proved challenging at first, but following his further research and guidance from his county’s Farm Service Agency, Barbour has now performed all three types of grazing on portions of his two neighbors’ CREP CP-1 lands for six of the last seven years.

Notably, 2018 marked the first time Barbour obtained permission for prescribed grazing, defined by NRCS as “the controlled harvest of vegetation with grazing animals, managed with the intent to achieve a specific objective.” Barbour used the prescribed grazing to target noxious weeds — in an environmentally friendly way that benefitted both CREP-enrolled acreage and his own pastures.

Realizing the value of knowing one’s foe, Barbour first learned all he could about the Canada thistle. Most people recognize this weed’s tall mid-summer profile, and some know that each plant’s flowers yield thousands of seeds spread by the wind or by mowing at the wrong time. However, Barbour found that the key to controlling this prickly perennial is understanding its extensive root system. Not only do these roots reach a depth that is at least twice the plant’s height, but the Canada thistle root system also extends up to a quarter mile from the plant it sustains. Realizing this, Barbour determined that, while eradication of this nuisance plant is unlikely, suppressing it is an achievable goal.

Attacking the root system is key, explains Barbour, because that’s where the plant’s energy is stored during the non-growing season. Thus, he said, any means to “disturb, stress, injure or exhaust the plant” is a major step toward controlling this weed. He also emphasized that success requires multiple treatments for multiple seasons, because there is no “silver bullet” for controlling Canada thistle.

Shunning chemicals in favor of the prescribed grazing route involved Barbour’s preparing an NRCS-compliant technical practice standard Code 528 Prescribed Grazing Plan. It specifies grazing between May 1 and Sept. 1 for a maximum of 30 days in any one area. Grazing is permitted for not more than three years in the same field, and Barbour must reapply to FSA annually for this grazing approval. Owners of the CREP land Barbour grazed his cattle on also had to agree to a 25 percent reduction in their annual CREP payment.

The specific practices in Barbour’s Prescribed Grazing Plan include grazing early and often; managing for consumption and compaction of the thistle by cattle’s nipping and injuring thistles without taking them down to the ground; improving the health and vigor of desirable forages; providing a high stock density of roughly 100,000 pounds per acre; and limiting grazing of any area to short duration — sometimes as brief as a single day, according to Barbour, who moved his cattle frequently.

Barbour said that achieving success requires getting cattle to graze thistle before it flowers and goes to seed. Since cattle need to enjoy what they’re eating, this grazing is best started early in the season before the thistle plants lignify and develop a woody texture that cattle find unpalatable. As he does elsewhere on his own rotationally grazed pastures, Barbour uses step-in posts and a spool of polywire attached to his belt to quickly create new grazing areas required for what he called “flash grazing.”

Photographs taken by Barbour showed that thistles were often nipped back in just one day’s time. He allowed the cattle to graze a CREP area until some bare ground was visible, but desirable grasses were not eaten lower than 5 or 6 inches. This permitted grass regrowth, which, over a period of time, lets the grass overtake the thistles, eliminating a possible thistle monoculture and allowing for a polyculture of assorted grasses and legumes. Barbour waits about six weeks to return and graze the same area again. He emphasized that he wants his cattle’s bellies full all the time, as he sets his butcher date a year in advance and must feed his finishers to that schedule.

Of his farm, Barbour said, “Our mission is to serve as healthy land stewards while providing high quality, ethically raised grass-fed beef.”

To that end, he has found controlling Canada thistle by judiciously planned grazing allows him and his CREP-enrolled neighbors to avoid the use of herbicides, while at the same time suppressing noxious weeds, improving soil conditions and promoting habitat diversity.

Although Canada thistles grow back quickly each year, they are not as dense as would be without the grazing, and therefore Barbour feels he is winning the battle, if not yet the war, against this weed.

For those interested in investigating grazing options for CREP-enrolled land, Barbour recommends starting with the local FSA office.

Further information about his farm is available online at

Sue Bowman is a freelance writer in southeastern Pennsylvania.