In the Weeds

Missoulians have proved they’re willing to pony up for open space. But with more on the horizon, are we willing to maintain it?

Imagine a walk in the North Hills in late spring. The hillsides are covered with rich yellow, deep purple, brilliant orange and white flowers, all interspersed with green grasses both short and tall waving in the wind. There’s a cacophony of bird song, with deer wandering across the horizon and cattle grazing in the distance. This was Missoula in the mid-1970s, when the landscape of the North Hills was predominately comprised of a diverse array of native species, including balsamroot, lupine, Indian paintbrush, yarrow, blue-bunch wheatgrass and June grass. This is what open space lands could and arguably should be: not entirely weed-free, but tipped in favor of natives.

Today, taking this same walk is a drastically different experience. There are a few scattered populations of native plant species, but noxious weeds are everywhere, in some cases forming monocultures.

This is open space. Missoula has amassed 3,300 acres and counting. Back in 1980 Missoula voters approved the city’s first open space bond in the amount of $500,000. With that money the city purchased the former Milwaukee railroad bed, now the Kim Williams trail, and 125 acres of Mount Jumbo, placing an additional 501 acres on the face of Mount Sentinel under conservation easement.

Fifteen years later, fear of impending development reached critical mass and, facing a population boom, a public/private coalition of Missoulians drafted the city’s first open space plan in 1995, setting goals and identifying key properties. With $5 million in new bond money, granted once again by voters, acquisitions were made and easements were established. Many of the purchases were accomplished in partnership with Five Valleys Land Trust, Rocky Mountain Elk Foundation and the Trust for Public Land, as well as agency partners such as the U.S. Forest Service and Montana Fish Wildlife & Parks.

Through this collaborative effort, 1,465 acres of Mount Jumbo, 949 acres of Mount Sentinel and 587 acres in the North Hills—including the Randolph Homestead—were acquired. In addition, a 120-acre conservation easement was established on the Schilling property in the North Hills, and 200 acres along the Clark Fork River west of Reserve Street were purchased, with another 80 acres placed under conservation easement.
Then, last year, voters yet again came out in support of local land-preservation efforts, passing yet another bond, this one for $10 million, with which the city has thus far acquired 40 acres adjacent to Kelly Island on the Clark Fork River. As for the rest of that $10 million, the city has only just begun to identify what Jacquelyn Corday, Open Space Program Manager for the city, calls “cornerstone” properties.

“The 1995 bond was very successful in the east and north, but now its time to do something for the South Hills,” she says.

But as Missoula continues to save more open space, it’s becoming clear that acquiring property is only the first step in a process that includes maintaining those lands. Unless you’ve just stepped off a bus from some suburbanized concrete world, or are simply in denial, you’re probably aware that the West has a weed problem, and it’s serious. By purchasing open space to save it from development, Missoula has helped address the number-one threat to species loss. The second-largest threat is weeds. Saving land is important, but it is not enough. In the coming years, caring for the land we’ve saved will be critical.

With the 1995 acquisitions, Missoulians inherited a damaged landscape. Between 1985 and 1995, according to the Bureau of Land Management, weeds spread across the West like wildfire, growing from an astounding 4 million acres to an appalling 17 million acres. In Montana, knapweed alone increased its hold from a few plants in 1920 to more than 5 million acres in 1995.

The Montana County Weed Control Act defines noxious plants as “plants of foreign origin that can directly or indirectly injure agriculture, navigation, fish or wildlife, or public health.”

Morgan Valliant, installed in May as Missoula County’s new conservation lands manager, says that of the 51 weeds recognized as noxious in Missoula County, knapweed, sulfur cinquefoil, leafy spurge and Dalmatian toadflax pose the greatest concern on open-space lands. Cheatgrass is also on his list of challenges, even though it’s not considered technically noxious due to its viability as livestock forage.

Missoula County harbors an estimated 600,000 acres of knapweed, 100,000 acres of sulfur cinquefoil, and 6,000 acres of leafy spurge. The local acreage of Dalmatian toadflax and cheatgrass remains un-estimated.

Unlike native species, exotic weeds have no native insects, fungi or diseases to control their growth or spread, freeing them to wreak havoc across the landscape and allowing them to beat out natives. But suppression of native plants is just the beginning. The impacts of noxious weeds can resonate throughout entire ecosystems. Leafy spurge can reduce land’s cattle-carrying capacity by 50 to 75 percent. Deer use of leafy spurge-infested areas is three times less, and bison use four times less, than in native bunchgrass-dominated landscapes. A 2003 study reported diminished grasshopper and savannah sparrow densities in areas of high leafy spurge cover. A 2006 study found that chipping sparrows exhibit delayed breeding, diminished productivity and reduced site fidelity in knapweed-invaded habitats.

In addition, many noxious plants produce highly toxic chemicals that have been known to injure and kill animals, and there are increasing area reports of people so allergic to knapweed their symptoms can be life-threatening.

Missoula’s efforts to steer open-space lands back toward native species and biodiversity—and away from exotics and monocultures—didn’t begin until 1998, when the city contracted Marilyn Marler, the natural areas coordinator for the University of Montana. At the time, Marler initiated the integrated management plan still being generally followed today, utilizing a variety of weed-control tools including grazing, hand-pulling, revegetation, biological controls (weed-eating insects) and herbicides. Of these, herbicide application remains the most effective and, arguably, most problematic.

Missoula City Council drafted its first vegetation management plan in 1999 for Mount Jumbo, which included the use of two herbicides, Tordon and Transline, effective at controlling knapweed, leafy spurge, dalmation toadflax and sulfur cinquefoil. Crews sprayed hundreds of acres of open space land using backpack sprayers, but the often steep turf proved difficult ground to cover on foot. Helicopter spraying was suggested as a solution.

Although a 1999 County Health Department report found that “human health and ecological risks from the use of picloram [Tordon] and clopyralid [Transline] on Mount Jumbo are minimal” and recommended aerial spraying, the proposition met with opposition. Women’s Voices for the Earth, a Missoula-based non-profit, spoke out the loudest, citing a lack of research on the cumulative effects of multiple chemicals in the environment as cause for caution. Many in the community agreed, and the use of helicopter spraying as a management tool was passed over.

Despite the controversy, herbicide use continues today, but Valliant says he’s focusing this expensive management tool, which costs an estimated $90 per acre, on what he calls “spot fires,” or areas of new or light weed invasion where invasive species have not yet solidified their footholds. Such a focus not only minimizes human-health risks and damage to neighboring native plants, but also reduces the possibility of creating an even bigger problem—one that highlights the multi-faceted difficulty of weed management.

While herbicide treatment is widely used to suppress exotic forbs, which include most of the noxious weeds managers battle, grasses are not negatively impacted. In many cases, herbicides will knock out the exotics while allowing grasses to surge to unnatural levels. This is not considered a problem if the grasses in question are native to the system. It is, however, a problem if the grass is itself an invasive weed. Wildlife biologist Yvette Ortega and research ecologist Dean Pearson at the Missoula-based Rocky Mountain Research Station recently completed a five-year study showing that when cheatgrass is present at even low abundance, the application of broadleaf herbicide allows this weedy grass to take off. By spraying herbicide in these instances, land managers often find that they’ve simply traded knapweed for cheatgrass.

Cheatgrass is an impossibly difficult weed to manage, more so even than the forbs the herbicides target, and has already taken root in overwhelmingly dense patches all over Missoula’s open space landscapes. Marler admits, “My biggest challenge is dealing with cheatgrass in super-degraded areas.” She has tried a new herbicide specifically targeting cheatgrass and followed these treatments with reseeding, with absolutely no success.

“I just haven’t found the right solution yet,” Marler says.

Exchanging one problem weed for another is vexing, but it becomes even more troublesome when the exchange is for a highly unmanageable weed that alters fire regimes. The cheatgrass problem is currently playing out its worst-case scenario in Nevada, where fire experts hold record heat, drought, and two years of optimal growing conditions for cheatgrass responsible for the extreme fire conditions being experienced there today. Cheatgrass matures early and dries into a thick bed of fuel easily ignited by lightning, sparks or even hot mufflers. More than 1 million acres in Nevada have already burned this year. To make matters worse, cheatgrass is a fire-loving annual, thus giving rise to a vicious cycle: Cheatgrass fuels fire and fire, in turn, encourages increased growth of cheatgrass. This cycle has already devastated the Great Basin area, which includes most of Nevada, half of Utah and parts of California, Idaho, Oregon and Wyoming where this invasive grass from the steppes of Russia has taken over millions of acres and fueled increasingly large wildfires.

In response to this threat, according to a recent article in the Idaho Statesman, the governors of Nevada, Utah and Idaho have pledged to work together to launch pilot rehabilitation projects in each state aimed at halting cheatgrass’ spread through aggressive re-seeding campaigns to restore native sagebrush and bunchgrasses.

The last thing western Montana needs is a weed to contribute to the area’s already disastrous fire seasons, let alone one unintentionally encouraged by management efforts.

“Mistakes are going to be made,” Pearson says, “but they need to be made in an adaptive management framework such that responses are monitored, and when it doesn’t look like it’s going right, changes are made. Only by integrating research and management will we be able to ensure we are in a better place 10 years from now.”

Valliant agrees: “As a land manager, the best thing you can have is someone doing research on the property you are managing.”

But it’s exactly such science, says Valliant, that’s lagging. “It helps to have hard science to inform decisions, but it often becomes available way behind management efforts already in place,” he says.

“It really is a matter of time and money.”

Money was found to purchase Missoula’s open-space lands, but in fact little money exists to manage them. The current city budget for open space management, Valliant estimates, is $15 per acre.

“Look at your own backyard and think about how much money you spend; $15 per acre of conservation land is not much at all.”

Lack of funds, public demand that managers do something about the weed problem and an already burdensome workload place managers in the position to have to make decisions quickly, and often without supporting data.

Giles Thelen, a research specialist with the University of Montana who studies the weed problem, points out an example.

“We were hiking up Mount Jumbo to do some work on a long-term study in a pristine area near the top on the backside,” Thelen recalls. “When we get up there we find sheep milling around, 550 of them. Two herders come up to talk to us, one is on horseback, the other on an ATV.”

“Five hundred and fifty is just too many sheep; the potential to heavily disturb that pristine area seems likely, especially when you throw in a horse and an ATV.”

The use of sheep to control weeds has been proven to halt seed production and reduce the density and biomass of noxious weeds. However, when not properly controlled, grazing can cause significant damage to a system, actually promoting the spread and survival of invasive weeds. Overgrazing can reduce native plant cover, disturb soils, weaken native communities and allow exotic weeds to gain a foothold. According to a 1994 study, invasive plant seeds can be transferred in the hair of animals and remain viable after passing through their digestive tracts.

“We need controls and comparisons to find out what the sheep are doing,” Thelen says. “If the city is willing to invest in a helicopter to drop fencing and water for the sheep, they should invest in assessing how grazing is working, and its impacts.”

Surprisingly, those assessments either don’t exist or are not being applied.

Thelen, chair of the Mount Jumbo Advisory Committee and a member of the Conservation Lands Committee, is very familiar with the research and monitoring activities on open space lands, and has for the last four years been urging the city to do more.

“I know it’s difficult given time and budget constraints,” he says. But “All the city has to do is pick up the phone…It wouldn’t take much for the city to find knowledgeable labor with such a rich resource of people here at the University to conduct important research that can inform management.

“It just seems so common sense to think about what we’re doing and the effects of these actions. The last thing we want to do is make the problem worse.”

Despite the difficulties, there have been successes.

Marler currently manages 500 acres of Mount Sentinel and property at Fort Missoula owned by the University, with impressive results. Marler is responsible for coordinating the restoration of the popular “M” trail through massive community weed-pulling events, which also serve to foster public awareness of the need to care for these lands.

And Marler sees public awareness as key to addressing the issue.

“If people are out touching knapweed, connecting to these plants, getting excited about plants, making an investment in restoration will become important,” Marler says. “Hand-pulling knapweed has worked better than I thought.”

But hand-pulling alone isn’t likely to solve Missoula’s open space problems.

“Sure it works,” Valliant says. “But 600,000 acres of knapweed…

“What we’ve started to do now, which I think is good, is begin to catalog the entire 3,300 acres, taking inventory, so we can put resources in the right place.”

But even so, part of the purpose of the inventory is to identify “write-off areas,” landscapes Valliant defines as 99 percent weed-invaded, landscapes that are effectively already too far gone to save.

“People don’t like to talk about write-off areas, but we need to reevaluate our goals as to whether we are going to restore or rehabilitate these lands,” Valliant says.

And Valliant’s job is increasingly complicated by people as well.

“A lot of the management of open space is a balancing act between restoration and recreation. Some people suggest the only way to restore these lands is to shut them down to people entirely.” In addition, he says, “People need to realize that they impact these systems, too. We are as much responsible for their current state as we are for their restoration.”

Increased communication between scientists and land managers needs to develop, and monitoring needs to be implemented, but getting citizens involved with the issue is perhaps the biggest challenge on the horizon. Open space is public property. Maintaining it is a public responsibility.

According to Marler, “The most important thing we can do now is to get people to not feel like it’s hopeless, and do something.”

To that end, Thelen coordinated a successful weed-pulling event this past May on Mount Jumbo, focusing on knapweed and cheatgrass. His multi-layered approach included educating pullers on plant identification, reseeding with native grasses, and awarding a $300 reward to the most successful pullers of each species. Five hundred pounds of knapweed came off the hill that day.

“We can get rid of knapweed in three, maybe five years through hand-pulling. It works, I’ve seen it work, there is data to support it,” Thelen says.

He just needs the people power to do it.

Marler agrees: “I just keep trying to come up with new ways to engage people.”

And Valliant, still new on the job, remains hopeful that Marler and others can connect people to the project.

“If there is a community that will go to work for these lands and can make change for the better, it’s Missoula.”

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