Riparian Wranglers

OSU animal scientist Tim DelCurto has studied many aspects of protecting riparian health in cattle grazing areas such as this stretch of Catherine Creek near Union. Photo: Bob Rost

Summers in northeastern Oregon are hot and dry. They begin in June when the temperature creeps above 80 for the first time and end in early October when snow dusts the tops of the Wallowa Mountains and winter settles in for the long haul. It is a land of little rain, largely unsuitable for most farming. But because of several small streams and rivers, it’s fine for grazing cattle.

Across Oregon, more than 30 million acres of land are actively grazed, most east of the Cascades and publicly owned. Beef is the second leading agricultural commodity in the state, with more than $619 million in farm gate sales in 2005. Around Union County, where Tim DelCurto has spent the last 13 years, cows are more populous than humans.

DelCurto, an Oregon State University animal scientist and the superintendent of the Eastern Oregon Agricultural Research Center, studies different management techniques for range cattle in riparian areas, the corridors along creeks and rivers. The areas play an important role in maintaining water quality and channel stability and are integral to fish habitat and ecosystem health. Riparian vegetation can also be a major source of forage, shade, and cooler temperatures in an otherwise sunlit landscape. To sum it up, says DelCurto, the areas along creeks and rivers are mighty attractive to cattle and that can cause all sorts of problems.

Of primary concern to rangeland and animal scientists is the overgrazing of riparian vegetation. Trees, shrubs, and sedges hold together many of eastern Oregon’s streams. Intense grazing at fragile times during the growing season can damage root systems and lead to decreases in bank stability, says Tamzen Stringham, a rangeland ecologist in OSU’s Department of Rangeland Ecology and Management. From there, it’s a short jump to increased erosion and elevated levels of channel sedimentation.

“It’s the sediment loads from unstable banks we need to worry about and manage for,” she says. “They’re bad for fish and bad for overall water quality.”

In the mid 1990s, in the wake left by failed antigrazing legislation, DelCurto received a grant from the U.S. Environmental Protection Agency to begin research and outreach programs for ranchers running cattle along the state’s eastern waterways. He says he’s been learning about and managing the interactions between cows and riparian systems ever since.

“We were in a situation where we knew we had a problem with cattle along streams, and we were given the opportunity to ask what we could do to change it,” says DelCurto, who uses the OSU-owned Hall Ranch, outside Union and the USDA Forest Service Starkey Experimental Forest and Range as working laboratories. “During the first four to five years of the project it became clear that we had a late-season grazing problem.”

DelCurto and other College of Agricultural Sciences researchers developed a modeling system that tracked the movements of the Hall Ranch cattle herd during different parts of the year. They found that in the early, cooler months of spring and summer, the cattle would visit nearby Catherine Creek to drink, then they would spread back out across the ranch to graze. Later in the summer when temperatures were scorching, the cows would not redistribute across the range after drinking. Instead they remained in the riparian area, grazing on the last green vegetation around.

“As we watched the locator dots on the screen we could tell the cows were staying put,” says DelCurto. “We had cows almost living in the riparian zone during a time of the year when the area is most fragile.”

DelCurto tested shifting his grazing schedules to coincide with earlier growth stages when the vegetation is more resistant to overgrazing. Later in the vegetation cycle, when overgrazing is more of a threat to overall plant health, he provided the cattle with supplemental water and feed away from the riparian area. The change kept the cattle from overgrazing the creek banks, which in turn limited soil erosion. The offsite supplements prevented weight loss and additional stress to the herd.

Changing grazing patterns has potential because it works with both the needs of the riparian system and the ranchers, says Aaron Stalker, a new faculty in OSU’s Department of Animal Sciences. The amount ranchers earn for their cattle is based on weight. Management options that protect that measure are more likely to be adopted and successful, he says.

DelCurto agrees. “We’ve spent a lot of time figuring out what makes these cattle tick and using that to our advantage. Managing the animal’s natural tendencies creates a range of challenges, but there are solutions that serve the cows, the system, and the ranchers.”

Salt licks, water tanks, feed supplements, and shade structures have all been used with varying levels of success to increase cattle distribution across the range. Fencing and herding have also been used to supplement biological management techniques, but Stringham says they bring problems with them. Herding is costly in terms of labor and time, and materials and maintenance for fences can be expensive. In addition, stream channels can change position in the landscape, she says. “The purpose is to prevent bank trampling and overgrazing, and sometimes a fence is the only option,” says Stringham. “But we have to be more creative than that. Oregon has the most progressive ranching community I’ve seen, but a lot of these men and women have been left with a legacy of trying to fix things that happened 100 years ago. They get blamed for a lot of damage they didn’t do, but they’re trying to fix the situation and we’re trying to help them.”

DelCurto has also looked at using radio frequencies to control the movements of the Hall Ranch cattle. Cows are ear tagged with radio receivers that beep and provide a mild electrical stimulus when they cross a boundary established by directional radio transmitters. When the cows move out of the area, the beeping and stimulus stop. It’s much like an invisible fence you might use to keep your dog at home. DelCurto says radio tags have potential but are currently too expensive and bulky for him to recommend them to ranchers as a practical means of management. However, if the technology becomes more efficient for use on cattle, he says it could provide an economic alternative to corridor fencing that is now being used in riparian areas.

“Anything we propose as a management tool has to make sense financially,” he adds. “When we can manage livestock with an eye to both economics and ecosystem health, we have an option that is likely to be adopted. But to manage cattle without an eye to the health of the cows or the cost of the system is asking for failure.”

DelCurto invites ranchers and skeptics out to the Hall Ranch to see for themselves that healthy cattle and healthy creeks are not mutually exclusive. He shows off the fat cows and lush riparian areas along Catherine Creek, but he acknowledges that the pastoral scene requires human intervention.

“The issue always comes down to who’s watching the cows,” says Stringham, who works with ranchers to develop riparian management strategies. “If you’re an active manager you can do some incredible things, but it all depends on how much you’re willing to do from day to day and over the years.”

A decade ago Oregon was rift with politics surrounding the relationship between cows and creeks. Today, on Hall Ranch and on many ranches around the state, ranchers are making decisions that will enable them to pass a new legacy on to their children—one of a shared landscape where healthy cows and healthy creeks coexist.

“I look at the world through rose-colored glasses,” says DelCurto. “I’ve always been an optimist, and I believe we can have a sustainable ranching industry. We’ve come a long way and we still have a long ways to go. But we’re on a path that is helping to ensure the future of ranching. Our goal is that in another 100 years families across eastern Oregon will still be running cattle and catching fish.”

Eastern Oregon Agricultural Research Center-Union Station