Diversity is strength, even among forests. In a paper published in Nature, researchers led by University of Utah biologist William Anderegg report that forests with trees that employ a high diversity of traits related to water use suffer less of an impact from drought. The results, which expand on previous work that looked at individual tree species’ resilience based on hydraulic traits, lead to new research directions on forest resilience and inform forest managers working to rebuild forests after logging or wildfire.
Surprisingly, says Anderegg, a forest’s hydraulic diversity is the predominant predictor of how well it can handle a drought.
“We expected that hydraulic traits should matter,” he says, “but we were surprised that other traits that a lot of the scientific community have focused on weren’t very explanatory or predictive at all.”
by Area Forester Manij Upadhyay
About a year ago, I transitioned from working in the Department of Forests in Nepal as a forest officer to the Virginia Department of Forestry. Here, I want to share some information about the community forest management system of Nepal, which is the most common practice.
Nepal is a beautiful landlocked country with a total population of 28.98 million people. The country covers a total of 56,827 sq. miles of land, which is approximately 40.4 percent forested.
The country is divided into three major geographic regions: the High Himalayas, the Middle Hills and the Lowland Terai. The elevation ranges from 230 feet above sea level to 29,028 feet. Two-thirds of the population live in the rural areas of Nepal and depend on agriculture and forestry for their daily livelihood. In these rural communities, firewood is the major source of energy to cook food. Also, rural people have to cut, collect and carry their firewood and livestock’s fodder and bedding materials from nearby forests.
By Mark Johnson
This huge yet little-known South American wilderness is under threat. But plans to turn it into a sustainable tourism hub will help protect its people and wildlife.
In the far north of Argentina lies a vast and extremely hot lowland known as the Gran Chaco. Were you to find yourself in it, as I did, you might kayak across a lily-filled lagoon and stumble into a solitary mansion peeking out above an endless sea of green.
It was here, at Estancia La Fidelidad, that eccentric rancher Manuel Roseo lived until 2011, when he was brutally murdered by criminals hoping to take his large (and little-touched) property. Thanks to the quick actions of Argentinian conservationists, provincial officials and the federal government, that tragedy had a silver lining with the birth of a new national park that could just shine a light on a forgotten South American wilderness.
El Impenetrable national park opened to the public in August 2017, following a telenovela’s worth of drama that included not only Roseo’s murder but the hunt for his missing heirs and a long legal battle to expropriate his land. At 128,000 hectares, it’s now the largest national park in northern Argentina and a beacon of hope for the entire Gran Chaco, which fans out into Paraguay, Bolivia and Brazil (where it is connected to the Pantanal region) and is South America’s second-largest forest ecosystem after the Amazon.
While the Amazon has become a rallying cry for environmentalists, the bulbous silk floss trees, towering cacti and bushy bramble of the Chaco are disappearing in relative silence. Never as well-known – or as protected – as the Amazon, the Chaco is fast becoming the domain of cattle ranches and soya farms.
By George Plaven
Timm Locke relishes a chance to drive around Portland and showcase the latest commercial buildings made with mass timber, a construction material that uses wood beams and panels instead of concrete and steel.
First stop: Albina Yard, a four-story office building that opened in 2016 featuring cross-laminated timber panels from D.R. Johnson, a lumber company south of Roseburg.
Every piece of cross-laminated timber — or CLT for short — is prefabricated, designed for a specific part of the building, said Locke, director of forest products at the Oregon Forest Resources Institute. That means buildings go up faster, with fewer workers.
Wood is also environmentally superior to steel and concrete, Locke said, because it sequesters carbon and takes less energy to produce.
“There are so many benefits, it doesn’t matter which one you choose to start with,” Locke said.
First developed in Europe, mass timber is now catching on in the U.S., and Oregon is working to position itself as the industry hub, kick-starting rural economies that have traditionally relied on forest products. On Aug. 1, Oregon became the first state to approve language in its building codes allowing for wood-framed buildings up to 18 stories tall.
By Adrian Higgins
A pear seedling selection named Bradford was cloned by the gazillion to become the ubiquitous street tree of America’s postwar suburban expansion. Then it turned invasive.
Carole Bergmann pulls her small parks department SUV into an aging 1980s subdivision in Germantown, Md., and takes me to the edge of an expansive meadow. A dense screen of charcoal-gray trees stands between the open ground and the backyards of several houses. The trees are callery pears, the escaped offspring of landscape specimens and street trees from the neighborhood. With no gardener to guide them, the spindly wildlings form an impenetrable thicket of dark twigs with three-inch thorns.
Bergmann, a field botanist for the Montgomery County Parks Department, extricates herself from the thicket and in the meadow shows me that what I take to be blades of grass are actually shoots of trees, mowed to a few inches high. There are countless thousands, hiding in plain sight in Great Seneca Stream Valley Park. If it were not cut back once a year, the meadow would become like the adjacent screen, wall upon wall, acre upon acre of black-limbed, armored trees worthy of Sleeping Beauty’s castle.
“You can’t mow this once and walk away,” said Bergmann, who began her 25-year career in the department as a forest ecologist but has been consumed by an ever-pressing need to address the escape of the Bradford pear and other variants of callery pear, a species that originated in China, along with other invasive exotics.
By Dr. Ranil Senanayake
What is known by science reveals the forest as an ecosystem of tremendous complexity. The trees, while providing the essential framework of a forest constitutes only a fraction of the total biodiversity. It contains a huge array of organisms, that continually change in form and function. Thus biodiversity is what gives a forest its identity. It should also be borne in mind that, from the small bushes of an area after a fire to the tall growth fifty years later, the species and architecture goes through many changes, and all these ecosystems are expressions of the growing, maturing forest.
The international response to the loss of natural forest ecosystems can be seen in the massive global investment in forestry. However, a great majority of these revegetation programs around the world do not seem to provide an environment that is hospitable for sustaining local forest biodiversity. A situation brought about by neglect of the ecological and biodiverse reality of a forest in project planning. There is no excuse to be found in the argument that there was no information. Forest Ecology has a long and distinguished history in the scientific literature. The result of this neglect was that institutional forestry activity was centered around the growing of even aged monocultures of fast growing trees with no requirement to attend to the rehabilitation of forests.
The discussions on the sustainable management of forests still lack clear definitions creating a sense of confusion in the identification of goals. For instance, the inability to distinguish between plantations and forests have allowed processes that have led to a massive reduction of forest biodiversity. A clear definition of ‘a Forest’ needs to be clarified and harmonized in statements transmitted from the CBD to the IPF or the CSD. As forests are biological entities, any criteria or indicator chosen to represent biodiversity status must be rooted in biological variables. The current practices of assessing physical cover alone will not adequately indicate forest quality and trends. In this context, socio-cultural values should also be incorporated into the setting of criteria and indicators. Further, for every acre of forest that stands today, hundreds of acres of forest have been lost in the surrounding countryside. Yet there has been no mention of the need for rehabilitation and recovery of the biodiversity status of such degraded lands. If these fundamental issues are not addressed, the loss of forests and biodiversity in these critical ecosystems cannot be contained.
By Dylan Love
Called Forester, this robot uses a technique called “sounding” to help arborists identify sick trees and diagnose them.
After hearing a radio program describe the labor-intensive work of forest pathologists — basically, tree doctors — Maksim Mikhailov had an idea: what if a robot helped collect their data?
Mikhailov is a 16-year-old student at ITMO University, the renowned science and technology institution in St. Petersburg, Russia. As a member of the school’s Youth Robotics Lab, he was perfectly positioned to bring his idea to life. With a full team working on the the project, the robot won the gold medal at last year’s World Robot Olympiad; it can record tree locations within a forest, identify their species, measure the widths of their trunks, and even identify if a tree is healthy or not.
Its name is Forester, and most of its job is to explore forests and hit trees with its mallet. It’s a robotic adaptation of a technique that human tree experts often use, called “sounding,” to help their appraisal of a tree’s health.
“The robot hits a tree and its microphone records the sound,” Mikhailov explained. “Since sick trees have cavities or low wood density in their trunk, they make a sound with a lower overall frequency than that of a healthy tree.” The robot makes use of an algorithm that analyzes the recorded sound to determine if it came from a healthy tree.
Forester also takes a photograph of the tree and feeds the image to a neural network, identifying 12 different species of trees with accuracy better than 90 percent.
Peter Krzystek, Professor for Photogrammetry and Remote Sensing at Munich University of Applied Sciences tells about new investigations into the 3D mapping of forests.
Modern remote sensing sensors offer completely new possibilities for an extensive and detailed 3D capture of tree populations, making it possible to map at very large-scale. In particular, LiDAR is today an established technique for fast and highly accurate 3D scanning from the aircraft, helicopter or drone where pulses of visible or near-infrared laser light at a particular wavelength are used to create 3D images. These 3D images are typically made up of a high density of data points, known as ‘point clouds’. The new full waveform technology, which reconstructs the complete path of the laser beam through the vegetation, makes it possible to map the forest structures in 3D more precisely. Moreover, digital aerial cameras enable a detailed reconstruction of the forest surface and provide – if fused with LiDAR data – extra spectral information in the infrared range for a characterisation of the tree species. All in all, these new technologies are ideally suited for the automatic and cost-effective collection and characterisation of forest stands.
By Maria Dolan
Austin, Texas, and King County, Washington, are testing carbon credits for planting and protecting urban trees.
The evidence is in: Urban trees improve air and water quality, reduce energy costs, and improve human health, even as they offer the benefit of storing carbon. And in cities across the country, they are disappearing.
A recent paper by two U.S. Forest Service scientists reported that metropolitan areas in the U.S. are losing about 36 million trees each year. The paper, by David Nowak and Eric Greenfield, was an expansion of the same researchers’ 2012 study that found significant tree loss in 17 out of the 20 U.S. cities studied.
This arboreal decline is happening even in some areas that promote “million-tree” campaigns, Arbor Day plantings, and street-tree giveaways. Cash-strapped municipalities just can’t find enough green to maintain the green. Additionally, many cities are adjusting to population booms, and to temperature increases and drought due to climate change—both conditions that can be hard on trees (while increasing their value as sources of cooling and cleaner air). There’s also a growing recognition of the inequity of tree-canopy distribution in many cities, with lush cover in wealthy neighborhoods and far fewer trees in disadvantaged areas.
To find more funding for urban trees, some local governments, including Austin, Texas and King County, Washington (where Seattle is located), are running pilot projects with a Seattle-based nonprofit called City Forest Credits (CFC). The nonprofit is developing a new approach: generating funding for city tree canopies from private companies (and individuals) that wish to offset their carbon emissions by buying credits for tree planting or preservation.
The vast majority of forest carbon credits worldwide have been issued for trees in tropical rainforests and other forests far from urban areas. A study released last year of the forest offsets in California’s cap-and-trade program found that they are effective at reducing emissions.