Treesearch

Intactness is a commonly used measure of ecological integrity, especially when evaluating conservation status at the landscape scale. We argue that in the large and relatively unfragmented landscapes of the Arctic and sub-Arctic, intactness provides only partial insight for managers charged with maintaining ecological integrity. A recent landscape assessment suggests that 95% of Alaska shows no measured direct or indirect impacts of human development on the landscape. However, the current exceptionally high levels of intactness in Alaska, and throughout the Arctic and sub-Arctic, do not...

Climate classification allows an efficient encapsulation of climate data into climate units. For North America and most of Central America during 20, 14, 13, 11, 10, 7, 5, and 1 thousand years ago (ka) and recent years, I applied a Köppen-Trewartha classification system, but with dry classes subsumed under primary thermal classes to preserve information. The boreal and polar classes decreased from a combined 70% of area during 20 ka until reaching 42% of area at 7 ka, after which the area remained relatively stable. Conversely, the subtropical and temperate classes increased from 25% of...

Almost half of all Americans (45 percent) reported that their lives were affected a lot by COVID-19 pandemic conditions in 2020 and experienced a lot of worry and stress on a daily basis (Gallup, Inc. 2021). Nevertheless, even more said that they thrived. The study of human populations is rife with such paradoxes, especially during moments of change, when habits are shaken but values are clarified. Even in relatively uniform social groups, the same event can spur a wide variety of responses.

Wildland fire management is a complex system with various scales, modes, plans, and operations. As with any system, fire management can be subject to stresses and strains that are, in some cases, easy to identify in isolation but highly challenging to diagnose at a system level. A suitable analogy is the homeostatic range in the human body - that is, the limits on levels such as body temperature, pH, and blood level. Modern medicine has a quantitative understanding of the normal, extreme, and fatal ranges of these indicators.

The COVID-19 global pandemic created dramatic change in nearly every facet of life, including how the Forest Service worked to fulfill its mission despite facing multiple unknowns fraught with risks. Preparing for and responding to wildland fire while reducing the likelihood that wildland fire responders would be exposed to COVID-19 created an unprecedented challenge.

In 2022 the US Forest Service launched an ambitious 10-year strategy to address the escalating wildfire danger in the U.S. “Confronting the Wildfire Crisis: A Strategy for Protecting Communities and Improving Resilience in America’s Forests” includes a 10-year plan to substantially increase the scale of forest health and risk reduction fuel treatments over the next decade. The plan expands and prioritizes treatments on 20 million acres on National Forest System lands, and 30 million acres of other federal, state, tribal, and private lands, targeting lands where wildfire ignitions will...

Land management legacies coupled with climate change have led to shifts in western ponderosa pine (Pinus ponderosa) forest structure and fire regimes. A growing body of evidence suggests that under increasing area burned at high-severity, warming and drought, ponderosa pine forests are vulnerable to conversion to alternate forest types or non-forest vegetation. However, the extent and direction of recent fire-induced changes in southwestern US ponderosa pine forests have not been subject to region-wide evaluation. Here, we assess recent fire effects in ponderosa pine forests using long-term...

Since 1972, the Landsat program has been continually monitoring the Earth, to now provide 50 years of digital, multispectral, medium spatial resolution observations. Over this time, Landsat data were crucial for many scientific and technical advances. Prior to the Landsat program, detailed, synoptic depictions of the Earth's surface were rare, and the ability to acquire and work with large datasets was limited. The early years of the Landsat program delivered a series of technological breakthroughs, pioneering new methods, and demonstrating the ability and capacity of digital satellite...

Sagebrush ecosystems of western North America are threatened by invasive annual grasses and wildfires that can remove fire-intolerant shrubs for decades. Fuel reduction treatments are used ostensibly to aid in fire suppression, conserve wildlife habitat, and restore historical fire regimes, but longterm ecological impacts of these treatments are not clear. In 2006, we initiated fuel reduction treatments (prescribed fire, mowing, and herbicide applications [tebuthiuron and imazapic]) in six Artemisia tridentata ssp. wyomingensis communities. We evaluated long-term effects of these fuel...

Falling trees and tree fragments are one of the top five causes of fatalities for wildland fire responders. In six out of ten recent years, at least one fatality from a tree strike has occurred while a fire responder was on duty, and others were injured. We used TreeMap, a national map of forest characteristics, including individual tree height, diameter, and status (live or dead), to generate a map of snag hazard for forested areas of the continental U.S. at 30 x 30 m resolution. Snag hazard was classified into categories of low, moderate, high, or extreme based on snag density and...