Forest reserves expand by 95,000ha in Belarus over 5 years

MINSK, 15 September (BelTA) – Over the past five years the forest reserves in Belarus increased by 95,000 hectares, First Deputy Forestry Minister Valentin Shatravko told reporters at a press conference on 15 September, BelTA has learned.

“The Belarusian model of public forest management is gaining wider recognition at the international level, and there are grounds for this. Due to the efforts of domestic foresters, the quality of the forest reserves has improved. The area of forest reserves has been constantly growing over the past 30 years to reach 9.6 million hectares, the total forested area is 8.3 million hectares. The latter has grown by 95,000 hectares literally within five years,” the first deputy minister said.

Valentin Shatravko also pointed to the increase in the proportion of land area covered by forests. “The total reserves of plantings are also on the rise. Today they make up 1.838 billion cubic meters. The stock of mature and over-mature trees is also growing; it already amounts to over 400 million cubic meters. The average yield of wood per hectare keeps growing, too. Not it stands at 223 cubic meters per hectare. The intensity of forest use is consistently increasing throughout the country, which, among other things, has to do with an increase in the area under mature forests. At the same time, forestry industry complies with all environmental regulations. The efficiency of forest management is increased without jeopardizing the environment and biological diversity,” the first deputy minister emphasized.

“Within three years, all areas that were under forests are being reforested. Earlier, we were concerned by the drying out of pine forests, which peaked in 2018 and was aggravated by the drying up of spruce forests. But these days, the amount of forest restoration and recovery activities shrank by more than 10 times over 2018. This suggests that the situation has stabilized and is under control. Yet, forests are constantly monitored in order to prevent similar situations in the future,” Valentin Shatravko added.

Source: Forest reserves expand by 95,000ha in Belarus over 5 years – Belta, 2021-09-15

BGCI Launches the State of the World’s Trees Report

A third (30%) of the world’s trees are at risk of extinction.

  • Well-known trees such as magnolias and dipterocarps among most threatened, with oaks, maple (Acer) and ebonies also at risk.
  • Agriculture, logging, and livestock farming are the top threats but climate change and extreme weather are emerging dangers.
  • Islands including St Helena (69% of trees threatened), Madagascar (59%) and Mauritius (57%) have highest proportion of threatened trees.

Read the Report

(London, UK) — Today, Botanic Gardens Conservation International (BGCI) has published a landmark State of the World’s Trees report. The report, compiling work led by the Global Tree Assessment (GTA), is the culmination of five years of research to identify major gaps in tree conservation efforts. It is one of the first assessments of the world’s threatened trees.

Examining the globe’s 60,000 tree species, it reveals that 30% (17,500) of tree species are currently at risk of extinction. That means there are twice the number of threatened tree species globally than threatened mammals, birds, amphibians and reptiles combined.
Over 440 tree species are right on the brink of extinction, the report reveals, meaning they have fewer than 50 individuals remaining in the wild. These species are found all over the world, from the Mulanje cedar in Malawi, with only a few remaining individuals on Mulanje Mountain, to the Menai whitebeam found only in North Wales, which has only 30 trees remaining.

The report finds hope for the future, however, as conservation efforts led by the botanical community worldwide are growing. Identifying which trees are at risk and ensuring these are protected is the most effective way to prevent extinction and restore endangered species. The report reveals that at least 64% of all tree species can be found in at least one protected area, and about 30% can be found in botanic gardens, seed banks, or other ex situ collections, but further action is needed.

The State of the World’s Trees report brings together research from over 60 institutional partners, including botanic gardens, forestry institutions and universities worldwide, as well as more than 500 experts who have contributed to tree assessments in the last five years.

Source: BGCI Launches the State of the World’s Trees Report – Botanic Gardens Conservation International, 2021-09

Why the South is decades ahead of the West in wildfire prevention

“Florida has done prescribed burns on more than 1.6 million acres so far this year. California has only burned around 35,000 acres. The state is 2.5 times larger than Florida.”

By Lauren Sommer
In early May, flames began to spread through a pine forest, consuming a dense carpet of leaves and underbrush. The burn was the definition of a “good fire,” intentionally ignited to clear vegetation that could fuel future infernos.

It happened in the state leading the nation in controlled burns: Florida.

As Western states contend with increasingly catastrophic wildfires, some are looking to the Southeastern U.S., where prescribed fire is widespread thanks to policies put in place decades ago. From 1998 to 2018, 70% of all controlled burning in the country was in the Southeast.

While a continent apart, both regions have a similar need for fire. For thousands of years, forests and woodlands experienced regular burning, both sparked by lightning and used by Native American tribes, which prevented the build up of flammable growth. Without fire, the landscape is prone to intense, potentially devastating wildfires.

Despite that risk, Western states have struggled to expand the use of controlled burns. This month, the U.S. Forest Service suspended them because of the extensive fires burning in record-dry conditions.

Now, several Western states are moving to adopt the fire policies pioneered by Florida and other Southern states as a hedge against the future. They include training problems for burn leaders and providing liability protection for them. The bigger challenge is changing the culture around fire, so that residents know that tolerating a little smoke from good fires can help stop the destructive blazes that cloud the air for weeks.

“We have this generational gap in fire knowledge in the Western U.S. that we’re trying to rebuild now,” says Lenya Quinn-Davidson, a fire adviser for the University of California Cooperative Extension. “But Florida and the Southeast still have it.”

Source: Why the South is decades ahead of the West in wildfire prevention – Oregon Public Broadcasting, 2021-08-31

The burning debate — manage forest fires or suppress them?

By Char Miller
As western wildfires burn through millions of forested acres, they are igniting debates about our response that are almost as heated as the flames themselves.

The leaders of the U.S. Forest Service have known that fire begets discord since 1905, when Gifford Pinchot became the federal agency’s first chief. Randy Moore, who was sworn in as the 20th chief on July 26, is no stranger to the conflict, after his decade-long service as the agency’s regional forester for California. Since 2017, that fire-prone state — and its many national forests — have endured its eight largest fires ever.

Despite his extensive experience, Moore probably did not expect to be burned even before assuming his new post. But he was, courtesy of a lightning-struck, smoldering pine rooted in a granite-rough ridge in the Humboldt-Toiyabe National Forest in early July.

When the fire was spotted, Forest Service personnel determined there was no immediate danger of fire spread. They would monitor it. But for the health of the forest, where fire is regenerative, and for reasons of resource management and firefighter safety, this was the kind of fire they wouldn’t move immediately to put it out.

A week later, gusting winds fanned sparks outward, and what came to be known as the Tamarack fire has been burning ever since. Although the 68,000-acre blaze now is more than 80% contained, there has been no containing the resulting fight that erupted over the initial handling of the fire.

Angry California and Nevada politicians attacked the Forest Service’s decision not to extinguish the smoking tree. On July 20, Rep. Tom McClintock demanded that the outgoing chief retract the “current U.S. Forest Service direction that allows wildfires to burn and instruct all Regional Foresters that all wildfires should be suppressed as soon as possible.”

Moore responded with a memo Aug. 2. He conceded that in a “fire year different from any before” the Forest Service should stop managing fires for “resource benefit” — that is, to improve ecosystem health — and instead suppress them. “We are in a ‘triage mode,’” he wrote, and the agency’s focus now “must be on fires that threaten communities and infrastructure.” This was, he concluded, the most “prudent course of action now in a situation that is dynamic and fluid.”

Moore’s “prudent course … now” language, however, isn’t prudent enough for some. The National Wildfire Institute, a suppression-friendly bloc of retired Forest Service officials, said the initial Tamarack decision bore the “hallmarks of criminal negligence.” “It’s time,” they wrote in a letter to Moore, “to declare that all fires will be promptly and aggressively extinguished, period.”

But other Forest Service veterans disagree, urging the new chief to reverse his Aug. 2 directive.

Source: The burning debate — manage forest fires or suppress them? – pressofatlanticcity.com, 2021-09-01

Trees getting a nudge to help them adapt to warming climate

By Nelson Bennett
As the northern hemisphere experiences earlier, hotter, drier summers and heavier precipitation in the winters, due to global warming, natural selection should eventually result in trees naturally adapting to changing climatic conditions.

Tree varieties that thrive in warmer, drier southern parts of the province, or on lower slopes, are likely to gradually shift further north and further up mountain slopes.

Scientists and foresters in B.C. are already beginning to give them a gentle nudge through assisted migration – one of the topics this morning at the University of British Columbia’s ongoing three-day Commonwealth Forestry Conference.

Using a variety of scientific tools and experiments, like genomics and provenance trials, scientists have already been able to identify which tree varieties have naturally evolved certain traits, like cold hardiness, disease resistance and drought tolerance, in different geographic regions.

Climate data can be matched with tree phenotype data to identify which trees will be best suited to climate conditions in the coming decades. Genomics is an additional tool that helps scientists identify key genetic characteristics.

These tools are used to develop seed lots that foresters can use to replant trees in a given area that are the same species, but different varieties that have traits that make them more suitable to a climate that is changing rapidly.

Interior varieties of Douglas fir, for example, are more cold hardy than coastal varieties. And Sitka spruce from California grow longer and bigger than ones that grow in Alaska. They are the same species of tree, but are different varieties that have naturally adapted to their particular environments.

Scientists and foresters are already using these tools to identify which varieties might fare better in certain areas, and use them in what is called “assisted migration” using a climate-based seed transfer program.

To date, the climate based seed transfer program in B.C. has been optional, but will become mandatory next year, said Sally Aitken, a forestry scientist at UBC’s department of forest and conservation science.

Source: Trees getting a nudge to help them adapt to warming climate – Prince George Citizen, 2021-12-18

Yukon forests healthy with few areas of concern

By John Tonin
Yukon forests remain healthy according to the 2020 Yukon Forest Health Report, however, there are areas that foresters will be monitoring, said Rob Legare.

The Yukon Forest Health Monitoring Strategy focuses on the 10 forest health agents of greatest concern. The Yukon is divided into five forest health zones.

Each year since 2009, researchers have completed aerial surveys of one of the five zones. But, because of COVID-19, Legare said the aerial study was unable to happen in 2020. Instead, the information provided was an “anecdotal judgement” of what has been known to be occurring.

In 2021 foresters will be back in the air doing aerial monitoring in Zone 3, or the Dawson region.

Aerial surveys will be done in Zone 3 because of spruce budworm. In 2019 and 2020, residents of Mayo reported light defoliation on the tops of spruce trees in the Stewart Crossing area on Ferry Hill.

“When you see it (spruce budworm) in one area, it is very likely that it is in another area,” said Legare.

High budworm populations can result in defoliation ranging from light damage to growing tips to complete tree defoliation, reads the report.

Legare said their forester counterparts in the Northwest Territories have also been reporting budworm on the Yukon side of the border.

“They see it in the Yukon, they are seeing it in the Peel,” said Legare. “We don’t normally fly the Peel Watershed but we are including the Peel so we can start mapping spruce budworm because Northwest Territories’ forest health personnel are seeing it there.”

In the Shallow Bay area, there is “quite a bit of windthrow” said Legare. Windthrow refers to trees uprooted by wind.

“When there is windthrow of conifers that becomes available hosts for bark beetles,” said Legare. “The beetle likes trees that are stressed.

“What the risk is the large amount of windthrow could attract the beetle and populations can build up. We are monitoring those areas right now and doing some removal of host materials.”

Legare said there will be more information on the windthrow situation in the 2021 Forest Health Report.

Perhaps the largest area of concern still remains the territory’s aspen populations.

“The real extent of disturbance in the North is the aspen decline,” said Legare. “People up there have been noticing that the aspen just haven’t looked that healthy.”

Legare said the aspen decline could be attributed to climate change because it’s something that’s occurred in the last 20 years. Climate change can lead to changes in pest distribution, severity and frequency which contributes to aspen decline.

There are two species affecting the aspen decline, the large aspen tortrix and the aspen serpentine leafminer.

Outbreaks of large aspen tortrix have occurred in several places throughout the Yukon including Teslin Lake, Braeburn, Haines Junction, Pelly and Champagne. The tortrix eats the aspen leaves.

The leafminer pest occurs throughout the Yukon range of trembling aspen and also defoliates balsam poplar. The leafminer causes the aspen leaves to turn a milky white.

Although there are some areas of concern, Legare said when the aerial surveys are conducted foresters usually just see rows upon rows of beautiful, healthy trees and rivers.

Source: Yukon forests healthy with few areas of concern: report – Yukon News. 2021-07-03

Upward expansion and acceleration of forest clearance in the mountains of Southeast Asia

Yu Feng, Alan D. Ziegler, Paul R. Elsen, Yang Liu1, Xinyue He, Dominick V. Spracklen, Joseph Holden, Xin Jiang1, Chunmiao Zheng and Zhenzhong Zeng

Southeast Asia contains about half of all tropical mountain forests, which are rich in biodiversity and carbon stocks, yet there is debate as to whether regional mountain forest cover has increased or decreased in recent decades. Here, our analysis of high-resolution satellite datasets reveals increasing mountain forest loss across Southeast Asia. Total mean annual forest loss was 3.22 Mha yr−1 during 2001–2019, with 31% occurring on the mountains. In the 2010s, the frontier of forest loss moved to higher elevations (15.1 ± 3.8 m yr−1 during 2011–2019, P < 0.01) and steeper slopes (0.22 ± 0.05° yr−1 during 2009–2019, P < 0.01) that have high forest carbon density relative to the lowlands. These shifts led to unprecedented annual forest carbon loss of 424 Tg C yr−1, accelerating at a rate of 18 ± 4 Tg C yr−2 (P < 0.01) from 2001 to 2019. Our results underscore the immedi-ate threat of carbon stock losses associated with accelerating forest clearance in Southeast Asian mountains, which jeopardizes international climate agreements and biodiversity conservation.

Source: Upward expansion and acceleration of forest clearance in the mountains of Southeast Asia – Nature Sustainability, 2021-06-08

Throwing shade: Measuring how much trees, buildings cool cities

By Jeff Grabmeier
When the summer sun blazes on a hot city street, our first reaction is to flee to a shady spot protected by a building or tree.

A new study is the first to calculate exactly how much these shaded areas help lower the temperature and reduce the “urban heat island” effect.

Researchers created an intricate 3D digital model of a section of Columbus and determined what effect the shade of the buildings and trees in the area had on land surface temperatures over the course of one hour on one summer day.

“We can use the information from our model to formulate guidelines for community greening and tree planting efforts, and even where to locate buildings to maximize shading on other buildings and roadways,” said Jean-Michel Guldmann, co-author of the study and professor emeritus of city and regional planning at The Ohio State University.

“This could have significant effects on temperatures at the street and neighborhood level.”

For example, a simulation run by the researchers in one Columbus neighborhood found on a day with a high of 93.33 degrees Fahrenheit, the temperature could have been 4.87 degrees lower if the young trees already in that area were fully grown and 20 more fully grown trees had been planted.

Guldmann conducted the study with Yujin Park, who did the work as a doctoral student at Ohio State and is now an assistant professor of city and regional planning at Chung-Ang University in South Korea, and Desheng Liu, a professor of geography at Ohio State.

Their work was published online recently in the journal Computers, Environment and Urban Systems.

Researchers have long known about the urban heat island effect, in which buildings and roadways absorb more heat from the sun than rural landscapes, releasing it and increasing temperatures in cities.

One recent study found that in 60 U.S. cities, urban summer temperatures were 2.4 degrees F higher than rural temperatures – and Columbus was one of the top 10 cities with the most intense summer urban heat islands.

For this new study, Guldmann and his colleagues selected a nearly 14-square-mile area of northern Columbus that had a wide range of land uses, including single-family homes, apartment buildings, commercial and business complexes, industrial areas, recreational parks and natural areas. More than 25,000 buildings were in the study area.

The researchers created a 3D model of the study area using machine-learning techniques which combined 2D land cover maps of Columbus, as well as LiDAR data collected by the city of Columbus from an airplane. LiDAR is a laser sensor that detects the shape of objects. Combining this data resulted in a 3D model showing the exact heights and widths of buildings and trees.

They then turned to computer software that calculated the shadows cast by each of the buildings and trees in the study area over the course of a one-hour period – 11 a.m. to noon – on Sept. 14, 2015.

In addition, the researchers had data on land surface temperatures in the study area for the same date and time. That data came from a NASA satellite that uses Thermal Infrared Sensors to measure land surface temperatures at a resolution of 30 by 30 meters (about 98 by 98 feet). That resulted in surface temperatures for 39,715 points in the study area.

With that data in hand, the researchers conducted a statistical analysis to determine precisely how the shade cast by buildings and trees affected surface temperatures on that September day.

Results showed that, as expected, buildings turned up the heat in the area, but that the shadows cast by them also had a significant cooling effect on temperatures, particularly if they shaded the rooftops of adjacent buildings.

The statistical model could precisely calculate those effects, both positive and negative. For example, a 1% increase in the area of a building led to surface temperature increases between 2.6% and 3% on average.

But an increase of 1% in the area of a shaded rooftop led to temperature decreases between 0.13% and 0.31% on average.

Shade on roadways and parking lots also significantly decreased temperatures.

“We learned that greater heat-mitigation effects can be obtained by maximizing the shade on building rooftops and roadways,” Guldmann said.

Results also showed the importance of green spaces and water for lowering temperatures. Grassy areas, both shaded and exposed, showed significant heat-reducing effects. However, the impact of shaded grass was stronger than that of grass exposed to direct sunlight.

The volume of tree canopies and the area of water bodies also had significant cooling effects.

In the simulation run in the Columbus neighborhood, the researchers calculated that if the current trees there were fully grown, the temperature on a 93.33-degree F day would be 3.48 degrees lower (89.85 degrees).

But that’s not all. The simulation showed that if the neighborhood had 20 more full-grown trees, the temperature would be another 1.39 degrees lower.

Source: Throwing shade: Measuring how much trees, buildings cool cities – Ohio State News, 2021-06-24

Why trees grow at night

By Swiss Federal Institute for Forest, Snow and Landscape Research WSL
Trees form new cells by using the carbohydrates they produce through photosynthesis. However, it is not primarily the availability of carbohydrates that limits growth, but the water tension in the tree, the so-called water potential, as this study recently published in the journal New Phytologist shows.

The international research team led by Roman Zweifel at the Swiss Federal Institute for Forest, Snow and Landscape Research WSL has come to the surprising conclusion that trees grow primarily at night, and that this trend is largely explained by the level of air dryness. In the world’s first comprehensive study of radial stem growth with an hourly data resolution, the scientists analyzed data recorded over up to eight years on 170 trees of seven common species located at 50 sites all over Switzerland (> 60 Mio data points). Researchers from ETH Zurich and other research institutions in Switzerland and Europe were involved in the study. The sites investigated are part of TreeNet, a network in which stem radius changes of trees have been measured continuously using high-precision point dendrometers in parallel with information about the dryness of air (vapor pressure deficit, VPD) and soil (soil water potential) in Swiss forests since 2011.

The data show that the probability of tree growth varies significantly over the 24 hours of a day: stems shrink under the effect of water stress and expand in a range of 1-200 µm per day, and these fluctuations are superimposed on growth rates of 1-5 µm per hour.

Air humidity is key to tree growth

The research team concluded that VPD plays a key role as it allows for growth mainly at nighttime. In their study, during day time, high VPD severely limited radial stem growth and allowed only little growth, except in the early morning. “The biggest surprise to us was that trees grew even under moderately dry soil conditions when the air was humid enough. Conversely, growth remained very low when the soil was moist but the air was dry,” recalls Roman Zweifel, lead author at WSL. The reason for this is the limited water transport capacity of the trees: as soon as the air becomes drier, trees temporarily lose more water through transpiration than they absorb through their roots. The entire tree comes under tension, its water potential decreases, and growth stops regardless of the availability of carbohydrates.

Source: Why trees grow at night – Phys.org, 2021-06-21

Glyphosate pesticides persist for years in wild plants and cause flower infertility

An herbicide widely used in agriculture, forestry and other applications can cause deleterious effects on the reproductive health of a common perennial plant found in forests in British Columbia, Canada. Researchers reported in the journal Frontiers in Plant Science that glyphosate-based herbicides (GBH) deformed various reproductive parts on prickly rose (Rosa acicularis) a year after the chemicals were first applied in both field sites and experimental plots.

The study is one of the first to look at the effects of GBH on the reproductive morphology of a prevalent perennial plant in a commercial forestry operation. The herbicide is commonly used to control plants that could compete with conifers that are grown to be harvested in areas known as ‘cutblocks’. Glyphosate has been used since the 1970s but has come under increased scrutiny in recent years over concerns about carcinogenic effects on human health.

Investigators from the University of Northern British Columbia (UNBC) collected and analyzed samples of prickly rose reproductive parts from three cutblocks, as well as from greenhouse-grown wild plants, and compared them against untreated plants from similar sources.

The results were striking: Pollen viability of plants treated with glyphosate dropped by an average of 66% compared to the controls a year after the initial application. More than 30% of anthers, the part of the stamen that contains the pollen, failed to split open (a process known as dehiscence), condemning these flowers to functional infertility. In addition, researchers found traces of GBH on plant flowers two full years after the herbicide was first sprayed.

Source: Glyphosate pesticides persist for years in wild plants and cause flower infertility – EurekAlert! Science News, 2021-06-16