Citizen scientists can help study, halt die‑off of Pacific Northwest’s redcedars

by Seth Truscott
Washington State University scientists seek help from residents of the Pacific Northwest in tracing the worrying die-off of an iconic forest tree, the western redcedar.
A distinctive, useful, and beautiful giant, the western redcedar has historically provided Native American tribes with much of the materials for practical objects and culture. Valued for its natural beauty and soft, red timber, which resists decay and repels insects, redcedars can reach nearly 200 feet in height and live for more than a thousand years.
Western redcedars are found throughout the Northwest due to their tolerance for shade, flooding, and poor soils, thriving where other trees cannot.
Over the last few years, however, scientists have observed an increasing number of dead and dying trees. Mortality begins with dieback, in which the tops and branches die from the tips. Some specimens survive, but the condition can also kill.
Joseph Hulbert, postdoctoral fellow in WSU’s Department of Plant Pathology, founded the Forest Health Watch program to enlist citizen scientists in understanding and preventing dieback.
Researchers believe the problem is spurred by longer, hotter droughts in the region. But it’s unclear if precipitation, temperature, consecutive dry days, or other environmental factors are the main factor.
Launched in 2020, Forest Health Watch seeks answers. Citizens help by logging and photographing sites where trees are healthy, dead or dying back. People can also identify sites and conditions where trees may be vulnerable, and watch for signs of disease or pests.
“Anyone can be a community scientist,” Hulbert said. “All you really need is a camera for this project.”
Hulbert launched the Western Redcedar Dieback Map on the iNaturalist citizen science website to allow citizens to easily log their sightings.
“Once we have a strong understanding of the areas where trees are vulnerable, we can begin to explore options for keeping trees healthy in those areas,” he said.

Source: Citizen scientists can help study, halt die‑off of Pacific Northwest’s redcedars – WSU Insider, 2021-03-19

Penn State DuBois professor has the ‘dirt’ on sustainable urban forests

New research published by Robert Loeb, a professor in biology and forestry at Penn State DuBois, outlines his efforts to bring the experience of rural forests to those who live in cities, with an eye toward what Loeb calls “environmental justice.” The article appears in the April issue of the publication Urban Forestry and Urban Greening.

Loeb’s article details new research discoveries about urban forests that veer from his typical concentrations. For decades he has studied forests in locations like New York City and Nashville, stewarding forest regeneration by examining the impact that wildlife and humans alike have on the forest and finding ways to curb this impact. This has led to work in a new urban-forest management protocol, “SAFE” — Soils, Aliens, Fire, Exclosure — with the goal of increasing natural regeneration through soil treatments, alien species treatments, fire surveillance, and fencing to eliminate problematic browsers such as deer.

Loeb took a turn toward research in soils when in 2014 he began to study tree regeneration in an urban forest in Philadelphia known as “The Good Woods,” part of the larger Haddington Woods in Cobbs Creek Park.

“The Good Woods is exceptional in having a mature canopy, a normal layer of leaf litter and organic matter, a large number of native tree seedlings, and less herbivory than typically expected,” said Loeb. “During 2015, an exclosure fence for deer was placed around the Good Woods and an act of arson caused a ground fire in approximately half of the forest.”

What sets the Good Woods apart from other similarly situated urban forests is that many native species seedlings and saplings grow naturally below the canopy created by larger trees. Loeb’s goal is to determine why this happened at this particular site, to hopefully replicate the natural tree regeneration in other cities.

Loeb recalled, “Growing up in the Bronx, I was accustomed to seeing urban forests with only tall trees. One summer I was awarded a scholarship from the Student Conservation Association to conduct research in Vermont. What struck me the most was that the forests there had seedlings that are lacking in urban areas. I’ve been trying throughout my career to sort out this lack of natural regeneration so that people in urban settings can enjoy the beauty of rural forests when we visit urban forests.”

The most trusted theory Loeb has on the difference in soil composition impacting the natural regrowth of new trees is one that he believes is rock-solid, so to speak.

“If you have more rocks, you have less soil. So, naturally you have a smaller population of trees,” he said. “I found many of the urban parks to have a great number of stones and even boulders in the soil. One particular area of the Good Woods is almost free of stones, and the soil there supports a greater growth of young trees.”

These findings could go a long way in helping Loeb to recommend soil studies and remediation in other urban forests. “Soils are a critical issue and need to be treated,” he said. “When I was young, horticulturalists taught me that if you spend $100 to plant a tree, you spend $10 on the tree and $90 on the soil. That is a formula that has not always been in use recently, but a historical perspective that maybe we need to revisit now.”

Source: Penn State DuBois professor has the ‘dirt’ on sustainable urban forests – Penn State University, 2021-02-11

Transparent Wood Could Be the Window of the Future

By Amy Androff
Could looking through trees be the view to a greener future? Trees replacing the clear pane glass in your windows is not a work of science fiction. It’s happening now.

Forest Products Laboratory (FPL) researcher Junyong Zhu in co-collaboration with colleagues from the University of Maryland and University of Colorado, have developed a transparent wood material that may be the window of tomorrow. Researchers found that transparent wood has the potential to outperform glass currently used in construction in nearly every way.

Their findings were published in the Journal of Advanced Functional Materials in their paper, “A Clear, Strong, and Thermally Insulated Transparent Wood for Energy Efficient Windows.”

While glass is the most common material used in window construction it comes with a costly economic and ecological price.

Heat easily transfers through glass, especially single pane, and amounts to higher energy bills when it escapes during cold weather and pours in when it’s warm. Glass production in construction also comes with a heavy carbon footprint. Manufacturing emissions are approximately 25,000 metric tons per year.

Now, transparent wood is emerging as one of the most promising materials of the future.

Transparent wood is created when wood from the fast-growing, low-density balsa tree is treated to a room temperature, oxidizing bath that bleaches it of nearly all visibility. The wood is then penetrated with a synthetic polymer called polyvinyl alcohol (PVA), creating a product that is virtually transparent.

Source: Transparent Wood Could Be the Window of the Future – USDA, 2021-01-05

Research looks into 400 years of Pennsylvania’s forests, which have been ‘completely transformed’

By Marcus Schneck
Researchers at Penn State and other universities investigate historic influences on modern forests.

While forests of the northeastern U.S., from Pennsylvania north to Maine, may hold mostly the same tree species as they did 400 years ago, significant differences emerge under closer inspection.

“If you only looked at a tree species list, you’d have the impression that Northeast forests haven’t changed,” explained Jonathan Thompson, research associate at the Smithsonian Conservation Biology Institute. “But once you start mapping the trees, and counting them up, a different picture emerges. In some ways the forest is completely transformed.”

While forests of the northeastern U.S., from Pennsylvania north to Maine, may hold mostly the same tree species as they did 400 years ago, significant differences emerge under closer inspection.

“If you only looked at a tree species list, you’d have the impression that Northeast forests haven’t changed,” explained Jonathan Thompson, research associate at the Smithsonian Conservation Biology Institute. “But once you start mapping the trees, and counting them up, a different picture emerges. In some ways the forest is completely transformed.”

The researchers found that farming was the most significant factor in today’s composition of the forest. If more than half of a town was farmed, the local forests likely have changed considerably from their colonial-era selves.

But, even as the composition of the forests changes, the forest as a landscape type is resilient across the region and, short of significant human development, will return to that state, explained David Foster, director of the Harvard Forest.

Source: Research looks into 400 years of Pennsylvania’s forests, which have been ‘completely transformed’ – pennlive.com, 2019-11-21

The Survivors: Sugar Pine Trees and the Future Forest

By Kat Kerlin
CCalifornia’s drought and bark-beetle infestation killed more than 129 million trees between 2012 and 2016 in the Sierra Nevada. But amid the devastation stood some survivors.

At the time, UC Davis biologist Patricia Maloney and a team of researchers entered the forest to collect seeds from 100 surviving sugar pine trees. Alongside other parched sugar pines etched with the tell-tale tunnel marks of bark beetles, were green, healthy trees. The researchers spent the past two years raising 10,000 seedlings from 100 surviving mother trees around the Lake Tahoe Basin. They were first cultivated at the USDA Forest Service’s Placerville Nursery and then moved to the UC Davis Tahoe City Field Station.

This week, between 4,000 and 5,000 of the seedlings are being planted around Lake Tahoe’s North Shore as part of a restoration project funded by the Tahoe Fund and the California Tahoe Conservancy. About 1,500 will be used to study and identify important adaptive traits, and the remainder will be given to private landowners to plant.

f the seedlings turn out to be as genetically resilient as Maloney thinks and hopes they will be, these trees could represent the future forest, one better able to withstand the threats of climate change, including more droughts and bark beetle outbreaks.

“These survivors matter,” said Maloney, a scientist in the UC Davis Department of Plant Pathology and Tahoe Environmental Research Center. “Essentially, these are the offspring of drought survivors. This is hopefully the genetic stock of the future.”

Source: The Survivors: Sugar Pine Trees and the Future Forest – UC Davis, 2019-11-07

Professor conducts research using trees in Mexico

By Krissy Waite
For the past nine years, Paula Turkon, assistant professor in the Department of Environmental Studies and Sciences at Ithaca College, has been working on creating a timeline that can be used to date environmental and cultural changes in Northwestern Mexico using trees.

“The work that we’re doing is still preliminary,” Turkon said. “We’re building what we call a master sequence, and that can then be used to interpret things, but the construction of it is slow work because we don’t have anything to compare it to.”

Turkon’s research, “Chronology, Climate, and Culture in Prehispanic Mesoamerica: Contribution of Tree-Ring Studies,” aims to understand climate events — like droughts and heavy rainfall periods — and cultural changes in Northwestern Mexico using dendrochronology, or the study of tree rings. She said she became interested in this region when she was invited by her graduate school adviser to work there. Once there, she said, she wondered how people lived and produced food in such a dry environment.

The research is funded through a grant from the National Science Foundation. Turkon also works through Cornell University’s Tree-Ring Laboratory. She also works closely with colleagues at the National Institute of Forestry, Agricultural and Livestock Research and the National Institute of Anthropology and History in Mexico.

Turkon said her original research focused on understanding the degree to which people in this region were dependent on agriculture, which correlates with the amount of rainfall in the desert. She said she had trouble answering questions related to how agricultural and cultural changes happened because the data she had to reference were food remains, which are hard to put a date on. She said she also wondered if the variability of rainfall in the arid area was a factor in the past. She said she thought she could answer both questions using dendrochronology.

Dendrochronology is a technique in which the annual growth rings in trees, commonly known as tree rings, are studied to date events and environmental changes. Turkon said rainfall is the biggest factor that generally affects tree growth in the areas in Mexico where she takes samples. This means that a bigger, thicker tree ring could indicate a good rainfall year and a thinner tree ring could indicate a bad rainfall year. In Northern Mexico, it rains between 9.2 and 26.2 inches per year. Other factors, like the tree’s species, can also affect tree ring growth. Turkon said this technique has not been applied in this region of Mexico before.

Source: Professor conducts research using trees in Mexico – The Ithacan, 2019-11-06

Lost trees hugely overrated as environmental threat, study finds

Cutting down trees inevitably leads to more carbon in the environment, but deforestation’s contributions to climate change are vastly overestimated, according to a new study.

Deforestation for timber and farmland is responsible for about 92 billion tons of carbon emissions into the environment since 1900, found a study led by researchers at The Ohio State University and Yale University.

“Our estimate is about a fifth of what was found in previous work showing that deforestation has contributed 484 billion tons of carbon – a third of all manmade emissions – since 1900,” said Brent Sohngen, a professor of environmental and resource economics at Ohio State.He said that widely accepted estimate didn’t take into account the planting of new trees and other forest management techniques that lessen the environmental burden. The model used in this study did take those factors into account, which made a significant difference considering the intensive forest management happening in many parts of the world and the less-intensive, but not inconsequential, management that is happening elsewhere.

The study appears today (Nov. 4, 2019) in the Journal of Forest Economics.

“There was a significant shift toward treating forests as a renewable, rather than nonrenewable, resource in the last century, and we estimate that those reforestation and forest management efforts have led to a far smaller carbon burden on the environment,” Sohngen said, adding that the previous estimate was based on trees’ natural regrowth without any human intervention.

Source: Lost trees hugely overrated as environmental threat, study finds – Ohio State News, 2019-11-04

Radar vision in the mapping of forest biodiversity from space

By Soyeon Bae, et al
Abstract
Recent progress in remote sensing provides much-needed, large-scale spatio-temporal information on habitat structures important for biodiversity conservation. Here we examine the potential of a newly launched satellite-borne radar system (Sentinel-1) to map the biodiversity of twelve taxa across five temperate forest regions in central Europe. We show that the sensitivity of radar to habitat structure is similar to that of airborne laser scanning (ALS), the current gold standard in the measurement of forest structure. Our models of different facets of biodiversity reveal that radar performs as well as ALS; median R² over twelve taxa by ALS and radar are 0.51 and 0.57 respectively for the first non-metric multidimensional scaling axes representing assemblage composition. We further demonstrate the promising predictive ability of radar-derived data with external validation based on the species composition of birds and saproxylic beetles. Establishing new area-wide biodiversity monitoring by remote sensing will require the coupling of radar data to stratified and standardized collected local species data.

Source: Radar vision in the mapping of forest biodiversity from space – Nature Communications, 2019-10-18

Old friends and new enemies: How evolutionary history can predict insect invader impacts

By Michelle Ma
About 450 nonnative, plant-eating insect species live in North American forests. Most of these critters are harmless, but a handful wreak havoc on their new environment, attacking trees and each year causing more than $70 billion in damage.

The problem is, scientists often don’t know which insect will emerge as the next harmful invader.

A team led by the University of Washington, drawing largely on the evolutionary history of insect-plant interactions, has developed a way to understand how nonnative insects might behave in their new environments. The team’s model, described in a paper appearing Oct. 17 in the journal Ecology and Evolution, could help foresters predict which insect invasions will be problematic, and help managers decide where to allocate resources to avoid widespread tree death.

“What makes the bad invaders so special? That has been the million-dollar question, for decades,” said Patrick Tobin, an associate professor in the UW School of Environmental and Forest Sciences and one of the project leaders. “This has the potential to profoundly change how we predict the impact of nonnative species and prioritize limited resources used to mitigate these impacts.”

The new model can quickly evaluate whether a newcomer insect, even before it gets here, has a high probability of killing a population of North American trees. To use the model, all that’s needed is information about the insect’s feeding method (wood, sap or leaf feeder, for example) and what trees it feeds on in its native range. The model will then determine whether any North American trees are at risk of dying from it.

Whether a nonnative insect takes hold and becomes destructive has more to do with the evolutionary history between the new (North American) host tree and the insect’s native host tree from its home region, Mech explained. Molecular tools that allow scientists to construct comprehensive phylogenies (or maps) of how tree species evolved was key to the team’s breakthrough.

For example, if a pine tree in Asia and another in North America diverged tens of millions of years ago, the North American pine likely wouldn’t have retained defenses against an insect that only lives with the pine in Asia. Alternatively, two pines on both continents that share more evolutionary history and diverged more recently might still share similar defenses.

The new model helps identify the evolutionary “perfect storm” for conifers, where the invasive insect still recognizes the new tree as a food source, but the tree hasn’t retained adequate defenses to keep the invader in check.

Source: Old friends and new enemies: How evolutionary history can predict insect invader impacts – UW News, 2019-10-17

The Forest Service Is About to Set a Giant Forest Fire—On Purpose


By Maddie Stone
A man-made blaze on a remote Utah mountainside could provide valuable insights into the behavior of the powerful wildfires growing more and more common out West.

Sometime later this month or in early November, if the weather cooperates, the U.S. Forest Service will fly a pair of fire-spitting helicopters over a remote mountain in southern Utah and set the forest ablaze.

While the helicopters are pelting burning liquid fuel at the treetops, dozens of firefighters will be providing support on the ground, using drip torches and flamethrowers to create a towering wall of flame that will stretch from the forest floor to the sky. As the heat builds and the blaze roars across spruce- and fir-stippled canopies, a small army of scientists will launch weather balloons and drones, drive radar- and LIDAR-equipped trucks around the perimeter, fly specialized research planes overhead, and gather data on fire-hardened GoPro cameras to analyze the inferno from start to finish.

It will be among the fiercest controlled burns scientists have ever studied in the wild—“as close to a wildfire as you can expect,” says Roger Ottmar, the principal investigator for the Forest Service–led Fire and Smoke Model Evaluation Experiment (FASMEE). The goal? To collect data on every aspect of the fire at once, in order to improve the models scientists and land managers use to predict the impacts of fires. That will allow the agency to oversee more controlled burns on landscapes that need fire to thrive, and the data will also provide insight into the large, intense blazes that keep erupting across the West—the types of unruly fires that climate change and changing land-use patterns are making more common.

“The more experiments we can do, the better we can understand fire behavior in a changing climate,” says Craig Clements, the director of the Fire Weather Research Laboratory at San Jose State University and the science lead for FASMEE’s plume-dynamics and meteorology team. “This is the opportunity of a lifetime.”

The opportunity exists only because of the very specific ecological challenges facing Fishlake National Forest’s Monroe Mountain. The upcoming burn is part of a larger restoration project the Forest Service launched back in 2015 to revive the area’s ailing aspens, explains Linda Chappell, the regional fuels program manager. These trees, which provide food and shelter for a wide array of animals, including elk, rabbits, porcupines, beavers, and countless birds, have been declining across the West for decades due in part to overgrazing by deer and livestock. Drought and disease have hit hard, too. And aspens, a clonal species, need wildfires to cue their roots to put out new “suckers,” or sprouts. Around Monroe Mountain, the frequency of wildfires has dropped dramatically over the past century, allowing a mix of conifer species to slowly take over.

One of the most effective ways to bring aspens back is to ignite a “crown fire”: a really big, really hot fire that jumps from treetop to treetop and sends flames writhing upward into the sky. The work is being done piecemeal over the course of a decade in order to introduce as much variation as possible into the mountain ecosystem. “We want a crazy quilt of aspen ages and a crazy quilt of conifer ages,” Chappell says. Because these prescribed crown fires are so similar to wildfires in terms of their intensity, the restoration project served as the ideal natural laboratory for FASMEE to piggyback onto.

Source: The Forest Service Is About to Set a Giant Forest Fire—On Purpose – The Atlantic, 2019-10-24