Father-son research team discovers cheatgrass seeds survive wash cycle

Professor Hugh Lefcort and son Caleb examine the cheatgrass in Spokane, Washington. Credit: Gonzaga University

Not many sixth-graders can say they have been published in an academic journal, but Caleb Lefcort can cross that distinction off his list. Caleb got into a discussion with his father, Hugh Lefcort, professor of biology at Gonzaga University, as to whether the seed burrs from cheatgrass would survive the laundry cycle. Hugh believed the seeds would not survive. Instead of simply taking his father's word for it, Caleb -- who was in fourth grade at the time -- suggested the scientific method: an experiment.

The father and son duo set out to determine whether the seeds would survive the wash.
The experiment

Finding cheatgrass seeds was easy. Bromus tectorum (the scientific name for cheatgrass) is nearly ubiquitous in the Inland Northwest and has become an increasing concern throughout North America -- spreading rapidly through the western United States both through natural means and unintended ways, like getting stuck in people's socks and shoes.

"We hypothesized that laundering would impact water potential, and we, therefore, predicted that seeds would exhibit poorer germination and emergence after being laundered," said Hugh. "We also predicted that the effect of laundering would be stronger if bleach was used."

To collect the cheatgrass seeds, Hugh and Caleb walked through a nearby field wearing only socks on their feet. They divided the socks into three different treatments: 1. Not washed or dried; 2. Washed with detergent but not bleach and subsequently dried; and 3. Washed with detergent and bleach and then dried.

The socks that were to be laundered were divided into three different washing machines/detergent/dryer combinations:
1. A Whirlpool washing machine using All brand detergent and Whirlpool dryer;
2. A Samsung washer using Tide brand detergent and a General Electric dryer; and
3. A Maytag machine using Era brand detergent and a Maytag dryer.

Findings

The results of the experiment surprised both Hugh and Caleb.

"There was no significant effect of the different washing machines and their associated laundry detergents and dryers on the number of seeds that sprouted, nor did we find a significant effect of laundry treatments in the number of seeds that germinated," said Hugh.

There was, however, an effect on the seeds that were treated with bleach; they germinated at a slightly slower rate than the other seeds that were tested without bleach. The height of the plants that sprouted from these bleached seeds differed from the height of the plants that experienced the no-bleach-wash treatment.

The research that Hugh and Caleb conducted revealed that cheatgrass seeds and their germination processes are sturdy enough to survive the soaking, soap and agitation of washing machines, the heat of dryers, and often even bleach. Though they designed the study to make it difficult for cheatgrass seeds to germinate, they were surprised at how easily the treated seeds sprouted into plants. Government agencies may consider adding these findings to their public service announcements.

Caleb Lefcort is now a sixth-grader Moran Prairie Elementary School.

Source: Gonzaga University

Mountain pine beetles get bad rap for wildfires, study says

Following wildfires in 2011, a UW-Madison research team studied lodgepole pine trees in the Northern Rocky Mountains to examine whether earlier outbreaks of mountain pine beetles changed the ecological impact of the wildfires. Credit: Turner Lab

Mountain pine beetles get a bad rap, and understandably so. The grain-of-rice-sized insects are responsible for killing pine trees over tens of millions of acres in the Western U.S. and Canada over the last decade.

But contrary to popular belief, these pests may not be to blame for more severe wildfires like those that have recently swept through the region. Instead, weather and topography play a greater role in the ecological severity of fires than these bark-boring beetles.

New research led by the University of Wisconsin-Madison and the Washington State Department of Natural Resources provides some of the first rigorous field data to test whether fires that burn in areas impacted by mountain pine beetles are more ecologically severe than in those not attacked by the native bug.

In a study published this week in the Proceedings of the National Academy of Sciences, UW-Madison zoology professor Monica Turner and her graduate student, Brian Harvey, show pine beetle outbreaks contributed little to the severity of six wildfires that affected more than 75,000 acres in the Northern Rocky Mountains in 2011. They also show that the beetle outbreaks, which occurred from 2000 through 2010, have not directly impacted post-fire recovery of the forests. The study does not, however, address fire behavior, such as how quickly fires spread or how dangerous they are to fight.

While the findings may exonerate the insect scapegoats, they should also help ecosystem managers better respond to changes in the face of climate-driven disturbances, like drought and warmer temperatures.

Large, severe fires are typical in the lodgepole pine forests found throughout the region, even without mountain pine beetle outbreaks. However, as the climate has warmed, outbreaks and big fires have both become more common. The phenomenon of more beetles has meant more dead trees, and some have grown concerned about how beetle attacks and wildfires may interact.

"The conventional wisdom is that a forest of dead trees is a tinder box just waiting to burn up," says Turner, who has long studied the forest landscape of the Mountain West. "There were very little data out there but a lot of concern."

Forests attacked by bark beetles -- which burrow into the bark of lodgepole pines to mate and incubate their larvae -- can seem nothing more than ample kindling for a raging blaze, with their dead wood and dry, reddish-brown needles.

The burrows the beetles carve under the bark of pines, called galleries, choke off water and nutrient circulation in the trees. The trees die and, for the first couple of years, they hold on to their dry, lifeless needles. Scientists call this the "red stage," and some believe these trees could fuel more severe fires.

By year three, most beetle-attacked trees have entered the "gray stage," dropping their once green pine foliage, becoming needleless wood carcasses.

Earlier studies from Turner's group suggested that beetle outbreaks would not lead to more severe fires. But without actual fires, the interaction could not be tested.

However, in 2011, wildfires throughout eastern Idaho and western Montana -- in forests that had experienced varying mountain pine beetle outbreak impacts -- provided opportunity for the research team to begin to answer the question: Do the two disturbances, beetle attacks and wildfire, together change the ecological response of the forest to fire?

Fortunately for the team, among the burned areas studied were pine stands that had not been attacked by beetles. These areas served as controls. Others suffered a range of mortality from the beetles; in some stands, beetles killed nearly 90 percent of the trees prior to wildfire. The fires that raged also ran the spectrum of severity, allowing the researchers to compare a number of variables.

Some study plots comprised mostly live trees, while others contained mostly red-stage or gray-stage trees -- allowing the researchers to assess whether plots with red-stage trees (with dry needles) experienced greater levels of fire severity than plots with mostly gray-stage trees (no needles), as they and others had expected.

The study team examined ecosystem indicators of fire severity, such as how many trees were killed by fire and how much char covered the forests.

Engaging in what Harvey calls "post-fire detective work," in 2012, the scientific team evaluated fire severity in each study plot and stripped sections of bark from over 10,000 trees to determine what killed them, beetles or fire. Beetle galleries can remain visible under the bark even after fire.

As they sifted through the blackened trees and forest floor, the team became covered with ash and soot.

"We looked like coal miners when we were done," says Harvey.

They found that the severity of the outbreak and whether trees were in the red or gray stage had almost no effect on fire severity under moderate burning conditions.

Only under more extreme fire-burning conditions -- when it was hot, dry and windy -- did areas with more beetle-killed trees show signs of more ecologically severe fires, such as more deeply burned trunks and crowns (the part of the tree that includes its limbs and needles). The presence of more gray-stage trees actually had a stronger impact on fire severity than the amount of red-stage trees, to the surprise of the scientists.

Overall, however, Turner says the effects of beetle outbreaks on fire severity took a back seat to stronger drivers -- primarily weather and topography. Fire severity increased under more extreme weather, regardless of pre-fire outbreaks, and forest stands higher in the landscape burned more severely than those at lower elevation as fires moved uphill, building momentum.

"No one says beetle-killed forests won't burn," says Turner. "The data set looks at whether they burn with different severity compared to unattacked forests burning under similar conditions."

The team was also interested in whether beetle outbreaks slowed the recovery of the forests after fires. Lodgepole pines are adapted to fire, containing two types of seed-carrying cones: those that release seeds as soon as they mature and those that require fire to open, blanketing the forest floor with potential new life following a blaze.

By counting the number of post-fire tree seedlings in their plots, the researchers found very little beetle-related impact. Tree seedlings were most numerous where more of the fire-killed trees bore the fire-adapted, or serotinous, cones. Beetle-killed trees likely contributed to post-fire seedling establishment, too, as their seeds remain viable in cones if they are not consumed in fire. Only high-reaching char from tall flames reduced the number of seed-spreading cones.

The scientists emphasize the results may differ in other forest types or with different lengths of time between beetle outbreaks and fire.

"These are both natural disturbances, fire and beetle outbreaks," says Turner. "It's not surprising the ecosystem has these mechanisms to be resilient. What we as people see as catastrophes are not always catastrophes to the ecosystem."

Source: University of Wisconsin-Madison

Coexist or perish, new wildfire analysis says: Changing wildfire paradigm from fighting to coexistence

The lightning-sparked Castle Rock Fire burned nearly 50,000 acres in 2007 in the Sawtooth National Forest and adjacent state and private lands surrounding Ketchum, Idaho, in the Smoky Mountains region of the Rocky Mountain range. Credit: Kari Geer, courtesy of the National Interagency Fire Center

Many fire scientists have tried to get Smokey the Bear to hang up his "prevention" motto in favor of tools like thinning and prescribed burns, which can manage the severity of wildfires while allowing them to play their natural role in certain ecosystems.

But a new international research review led by the University of California, Berkeley, says the debate over fuel-reduction techniques is only a small part of a much larger fire problem that will make society increasingly vulnerable to catastrophic losses unless it changes its fundamental approach from fighting fire to coexisting with fire as a natural process.

The paper, "Learning to Coexist with Wildfire," to be published in the Nov. 6 issue of the journal Nature, examines research findings from three continents and from both the natural and social sciences. The authors conclude that government-sponsored firefighting and land-use policies actually encourage development on inherently hazardous landscapes, amplifying human losses over time.

"We don't try to 'fight' earthquakes -- we anticipate them in the way we plan communities, build buildings and prepare for emergencies. We don't think that way about fire, but our review indicates that we should," said lead author Max Moritz, Cooperative Extension specialist in fire at UC Berkeley's College of Natural Resources. "Human losses will only be mitigated when land-use planning takes fire hazards into account in the same manner as other natural hazards, like floods, hurricanes and earthquakes."

The analysis looked at different kinds of natural fires, what drives them in various ecosystems, the ways public response to fire can differ, and the critical interface zones between built communities and natural landscapes. The authors found infinite variations on how these factors can come together.

"It quickly became clear that generic one-size-fits-all solutions to wildfire problems do not exist," Moritz said. "Fuel reduction may be a useful strategy for specific places, like California's dry conifer forests, but when we zoomed out and looked at fire-prone regions throughout the Western United States, Australia and the Mediterranean Basin, we realized that over vast parts of the world, a much more nuanced strategy of planning for coexistence with fire is needed."

Planning for co-existence

If humans choose to live in fire-prone regions, fire must be managed on par with other naturally occurring hazards, the authors argue, and research must seek to understand what factors and outcomes we can and cannot affect.

One common tool is applicable to the vast array of ecological and social science interactions at the critical wildfire/urban interface: more effective land-use planning, along with the regulations that guide it.

The authors recommend prioritizing location-specific approaches to improve development and safety in fire-prone areas, including:

Adopting new land-use regulations and zoning guidelines that restrict development in the most fire-prone areas;

Updating building codes, such as requiring fire-resistant construction to match local hazard levels and encouraging retrofits to existing ignition-prone homes;

Implementing locally appropriate vegetation management strategies around structures and neighborhoods;

Evaluating evacuation planning and warning systems, including understanding situations in which mandatory evacuations are or are not effective;

Developing household and community plans for how to survive stay-and-defend situations; and

Developing better maps of fire hazards, ecosystem services and climate change effects to assess trade-offs between development and hazard.

As an example of positive steps, the report cites new fire danger mapping efforts, including an existing fire hazard severity zone map that guides building codes in California. Produced by the state's Department of Forestry and Fire Protection, the current map does not explicitly incorporate locally varying wind patterns, which influence the worst fire-related losses of homes and lives, but future iterations will include these data.

Fire ecology and climate

The authors underscore that wildfires are a natural part of many ecosystems and can have a positive long-term influence on the landscape, despite people labeling them as "disasters." They can stimulate vegetation regeneration, promote a diversity of vegetation types, provide habitat for many species and sustain other ecosystem services, such as nutrient cycling.

Around the world, the numbers, sizes, and intensities of fires vary greatly. In some ecosystems, big, severe wildfires are natural events and more climate-driven -- by drought or high winds -- so fuel reduction is not a very effective tool in these locations. By contrast, many ecosystems that would naturally experience frequent lower-severity fires may respond to vegetation management aimed at both reducing fire hazard to humans and restoring crucial ecosystem processes. But, the authors agree, where fuel reduction is an appropriate goal, it would ideally be achieved by letting wildfires do their job.

A changing climate will complicate management strategies.

"How should future fire patterns compare to this historical variability? That's the big question," Moritz said.

Describing wildfire as "one of the most basic and ongoing natural processes on Earth," the authors call for a paradigm shift in the way society interacts with it, changing to an approach that achieves long-term, sustainable coexistence that benefits the planet's ecosystems on the landscape scale, while minimizing catastrophic losses on the human scale.

"A different view of wildfire is urgently needed," said Moritz. "We must accept wildfire as a crucial and inevitable natural process on many landscapes. There is no alternative. The path we are on will lead to a deepening of our fire-related problems worldwide, which will only become worse as the climate changes."

Source: University of California - Berkeley

Even in restored forests, extreme weather strongly influences wildfire's impacts

Fire Sweeps Up, South Flank, Rim Fire. Credit: Mike McMillan - USFS

The 2013 Rim Fire, the largest wildland fire ever recorded in the Sierra Nevada region, is still fresh in the minds of Californians, as is the urgent need to bring forests back to a more resilient condition. Land managers are using fire as a tool to mimic past fire conditions, restore fire-dependent forests, and reduce fuels in an effort to lessen the potential for large, high-intensity fires, like the Rim Fire. A study led by the U.S. Forest Service's Pacific Southwest Research Station (PSW) and recently published in the journal Forest Ecology and Management examined how the Rim Fire burned through forests with restored fire regimes in Yosemite National Park to determine whether they were as resistant to high-severity fire as many scientists and land managers expected.

Since the late 1960s, land managers in Yosemite National Park have used prescribed fire and let lower intensity wildland fires burn in an attempt to bring back historical fire regimes after decades of fire suppression. For this study, researchers seized a unique opportunity to study data on forest structure and fuels collected in 2009 and 2010 in Yosemite's old-growth, mixed-conifer forests that had previously burned at low to moderate severity. Using post-Rim Fire data and imagery, researchers found that areas burned on days the Rim Fire was dominated by a large pyro-convective plume -- a powerful column of smoke, gases, ash, and other debris -- burned at moderate to high severity regardless of the number of prior fires, topography, or forest conditions.

"The specific conditions leading to large plume formation are unknown, but what is clear from many observations is that these plumes are associated with extreme burning conditions," says Jamie Lydersen, PSW biological science technician and the study's lead author. "Plumes often form when atmospheric conditions are unstable, and result in erratic fire behavior driven by its own local effect on surface wind and temperatures that override the influence of more generalized climate factors measured at nearby weather stations."

When the extreme conditions caused by these plumes subsided during the Rim Fire, other factors influenced burn severity. "There was a strong influence of elapsed time since the last burn, where forests that experienced fire within the last 14 years burned mainly at low severity in the Rim Fire. Lower elevation areas and those with greater shrub cover tended to burn at higher severity," says Lydersen.

When driven by extreme weather, which often coincides with wildfires that escape initial containment efforts, fires can severely burn large swaths of forest regardless of ownership and fire history. These fires may only be controlled if more forests across the landscape have been managed for fuel reduction to allow early stage suppression before weather- and fuels-driven fire intensity makes containment impossible. Coordination of fire management activities by land management agencies across jurisdictions could favor burning under more moderate weather conditions when wildfires start and reduce the occurrences of harmful, high-intensity fires.

Source: USDA Forest Service - Pacific Southwest Research Station