Tag: forestry and forest management and arboriculture

Building fire resilience with forest management in British Columbia

Key takeaways:

  • Across the globe, wildfires are increasing in size and frequency, driven by the effects of climate change.
  • In places like British Columbia, surging wildfires have meant that in recent years, some forests have been emitting more carbon than they have been able to absorb.
  • British Columbia can serve as an example for where wildfire mitigation occurs, to reduce the risk of threats to communities and forest ecosystems.
  • An essential step is reducing potential fuel for fires by removing flammable material on the forest floor and dead standing trees. The market for biomass encourages the removal of excess fibre which could become fuel for dangerous wildfires.
  • Collaboration between government, industry and First Nations in British Columbia ensures that forests are managed and protected to remain useful resources for all.

Forest fires are nothing new. Temperate forests throughout the world have evolved with fire over millions of years, and a certain amount of fire is inevitable and necessary to maintain the overall health of many types of forests.

But as global temperatures have increased in recent decades, so have the size and recurrence of wildfires. After Australia saw record heat in the summer of 2020, a series of fires across the continent burned an unprecedented 58,000 square kilometres (km2), an area larger than Costa Rica. While in 2022, Europe saw 7,850 km2 of forest destroyed in a single scorching summer, more than double the amount burned in an average fire season.

In addition to the effects of climate change, catastrophic wildfires have also prevailed in response to widespread fire suppression, when methods were sought to increase the resiliency of landscapes to fire and change forest stand characteristics. This has in turn led to thicker and denser forests, and increased fuel loading.

Prior to fire suppression, wildfires would have burned vast areas. In some cases, lower-intensity, stand-maintaining wildfires would naturally keep the forest understory clear of fuel loads. Fire suppression has instead led to increasing density in the forest understory, and when fire inevitably returns to those forest stands it creates conditions for high-intensity, stand-replacing fire events.

In Canada, British Columbia has not escaped these trends of larger fires.

About 64% of the province, more than 60,000 km2, is forested. This makes it particularly vulnerable to wildfire. In 2021 more than 1,600 separate fires burned nearly 8,700 km2 of land in the province, displacing thousands of people from their homes and wildlife from their habitats. Wildfires in the region also now average around 59 MtCO2 of emissions per year, 10x times the 1990s average, meaning that in recent years, British Columbia’s forests have been emitting more carbon than they have been able to absorb, becoming a source of CO2 rather than a sink.

In a region where forests are an important part of life, as well as an essential economic resource for rural communities, protecting forests from intense wildfires, and mitigating the effects, is crucial.

Delivering proactive management against wildfire

Managing forests to make them more resilient to wildfires requires careful management and collaboration between government, industry, communities, and First Nations.

The British Columbian government’s 2022 budget included CA$359 million in new funding to protect British Columbia from wildfires, including CA$145 million over three years to help move the BC Wildfire Service from a reactive to a proactive model. This means year-round work on four pillars of emergency management: prevention and mitigation, preparedness, response, and recovery.

The biomass industry has an important role to play in this work, incentivising fire mitigation and forest management which help protect forests for local communities to use and enjoy, as well as harvesting and regenerating fire-damaged land.

How forest management can protect forests against wildfires

For thousands of years, First Nations used small fires to clear forests, improving habitat for hunting and reducing the chance of large, uncontrollable fires.

While fire may be a natural part of the province’s landscape, active human management can help reduce the damage fires cause One key step is to remove the fuels that cause fires to burn and spread.

Fuels that feed wildfires consist of any burnable materials found on forest floors, ranging from grasses, dead leaves, and small trees to logs, stumps, and branches. Another fuel source are juvenile seedlings, sometimes called “ladder fuels” which move the forest fire from the ground into the forest canopy which often leads to fires that are much more severe and harder to suppress. Outbreaks of pests, like mountain pine beetle, also contribute to fuel loads, leaving large areas of dead wood.

Material accumulated on the forest floor over time can eventually become a source of what’s called ladder fuel that enables a relatively small fire to reach the forest canopy, burning higher, faster, and farther. These fuel loads, coupled with hotter temperatures and more frequent drought, make today’s fires more likely to burn larger and more intensely than their historic counterparts.

Removing sources of fuel and thinning the density of forest stands are sustainable management practices that can help mitigate the risk of the most damaging types of fires.

“When there’s less fuel to consume, future fire events will be lower in intensity,” says Mike Thomas, Regional Biomass Purchaser for Drax Canada. “And because they’re at low levels of intensity, the existing trees will live through the fire.”

However, removing fuel sources from forests can be expensive and historically has not been a priority for forestry operations focused on producing lumber and solid wood products. This makes biomass an important market, serving as a fibre purchaser for the low-grade wood removed in fire mitigation operations.

“Forest mitigation projects are very labour intensive and can be very expensive,” says Thomas. “The smaller material that we purchase from operators for pellet plants also helps to complete the projects. Without the biomass market, there would be less incentive to carry out these fire mitigation operations.”

Collaboration is key to lowering the amount of fuel in a forest

The type of sustainable forest management practices that reduce fuel loads require effort, know-how, and even the right market conditions. The key to implementing these practices is collaboration, between industry, government, and First Nations.

One example is the joint venture between the Tŝideldel First Nation (TFN) and the Tl’etinqox First Nation. The resulting company, called Central Chilcotin Rehabilitation (CCR), is involved in forestry projects, including fire rehabilitation, in the two groups’ traditional territories.

Forest area infected with the mountain pine beetle in British Columbia, Canada

The traditional land of Tŝideldel First Nation is largely lodgepole pine forest, which has been hard hit by mountain pine beetles and subject to frequent burning. In response, the Tŝdeldel have spearheaded several projects to remove dead standing trees and low-grade wood to reduce overall fuel load. Such projects aim to make the damaged landscapes productive, valuable resources once again.

Drax’s partnership with the Tŝideldel provides a crucial market for dead and low-grade wood removed from damaged forests, making it possible to finance forest management operations and reduce the chances of devastating wildfires.

A proactive example for the future

British Columbia offers an example of how smart, proactive forest management can play an important role in reducing the risk of catastrophic fires and making them more resilient to the effects of climate change.

Therefore, by working with the wider forestry sector, the biomass industry can help to facilitate important wildfire mitigation projects, ensuring forests and communities are protected, and all those who use them can continue to depend on them as a vital resource.

Ensuring British Columbia’s forests offer a sustainable source of fibre takes collaboration and careful management

Diane Nicholls, Vice President of Sustainability for North America, Drax

Key takeaways: 

  • British Columbia is 94% provincial Crown Land, meaning its 55-60 million hectares of forest cover is publicly owned, rather than privately held.  
  • Government legislation and regulation exists detailing what forestry practises can take place, working alongside First Nations, to ensure forests are used for the benefit of all.
  • Sustainable forest management practises offer a source of fibre for forest industries while also protecting forests from disease and wildfire.  
  • Although the biomass pellet industry is relatively new to the province, it offers a use for forest residues that were previously burned or landfilled, and for sawmill residues.  

As a business operating in the Canadian forest industry, we have a responsibility to work collaboratively with local and national governments, communities, and First Nations to ensure British Columbia’s forests are sustainably managed, protected from disease and fire, and preserved for future generations.  

British Columbia is a vast and diverse landscape. The second largest of Canada’s provinces, it contains 14 different bio geoclimatic zones ranging from coastal forest in the west, to alpine meadows on the eastern Rocky Mountains, with bogs, wetlands, and even arid land in between.   

The landscape of British Colombia is home to a wide range of flora and fauna. With roughly 55-60 million hectares (550,000-600,000 km2) of land covered in forest, it is a vital resource. More than 50,000 British Columbians work directly in the forest industry and even as cities like Vancouver and Victoria grow, it remains a central source of social value to rural economies.  

Sharing forests between government and First Nations

British Columbia has a long history of stewardship and sustainable forest management practices. Forestry began in the region in the 1800s with Sitka spruce, harvested predominantly to support ship building. Since then, forestry has become a major part of the province’s economy and the province is a world leader in sustainable forest management and environmental practises. 

As 94% of British Columbia is provincial Crown Land, the government sets the rules and regulations about what forestry practices, or any other natural resource extractions, can take place. Under legislation, any land where forest harvesting occurs must be reforested and it is illegal for a company to deforest British Columbia or Canada.   

For many years, an increasingly important component of the Canadian forestry industry has been the contribution that First Nations are making. There are 204 First Nations across British Columbia each with traditional territories used for cultural and spiritual purposes, as well as day-to-day needs like hunting, fishing, trapping, and housing.  

Many First Nations have their own land use plans that are utilised in forest management planning in the province. First Nations are also consulted and collaborated with by the province on forest management decisions. This creates partnerships between First Nations, industries working in the province’s forests, and governments at the provincial and federal levels. 

Protecting forests from pests and fire

Forest infected with mountain pine beetle in British Columbia

Managing forests is crucial to their longevity and ensuring they remain healthy and useable for future generations. This includes forestry practices to protect them from pests and the growing threat of forest fires.  

In 2017 and 2019 we saw the largest catastrophic fires we’ve ever had in British Columbia. At times it felt like the whole province was on fire. More recently, 2020 was another terrible year. Factors like climate change and storms are increasing the number of fires we see, but the intensity of fires is also exacerbated by debris left on forest floors from relatively recent mountain pine beetle infestations and other insects or diseases affecting forest health.  

 In the 1990’s several relatively warm winters led to the mountain pine beetle becoming endemic, and over the next 15 years millions of hectares of pine forest were lost to the bug. The government increased the allowable annual cut (harvesting levels) to remove the debris of such infestations which become dangerous fire hazards if not removed. 

To protect from fires, pests, and diseases, it’s important to open up forests through managed removals. This process creates more space and less dense stands of trees. It’s also crucial to reduce what’s left lying on the forest floor after forestry operations, while ensuring that the right wood is left to encourage biodiversity, soil health and habitat needs.  

These sustainable management practises are important to help the resilience of the forest and biomass offers a use for much of the wood removed through these practices that is not able to be manufactured into lumber.  

Biomass and the wood industry

Compared to lumber manufacturing, pellet production is relatively new to British Columbia’s forest industry, but it offers a practical use for materials that are unmerchantable or unsuitable for sawlogs. This includes, but is not limited to, forms of forest residues such as low-grade wood, treetops, and branches that are left behind from harvesting activities.   

Removing forest residues can provide more growing sites for new seedlings and helps to prevent intense forest fires. Slash and other low-grade wood are often simply burned along roadsides, but pellets offer a way to turn this fibre into a source of renewable energy. 

Forest residues from harvests, like slash and low-grade roundwood, accounted for approximately 8% and 10% of the fibre used in our Canadian pellet plants in the first half of 2022. The rest of the fibre we use comes from sawmill residues, such as wood chips, shavings, and sawdust. 

Drax operates eight pellet mills across British Columbia and two in neighbouring Alberta, but doesn’t own forests or carry out harvesting or wood sorting. Instead, we partner with forest companies that operate sawmills. These companies are awarded forest tenures, which allow them to harvest certain forest areas (which are identified by the provincial government) to produce solid wood products, which lock in carbon for years. In return, we obtain their sawmill residues. The economics of the wood pellet industry means the main driver of harvesting is still demand for high-grade timber.    

Through collaboration with our partners across the province, we help ensure British Columbia’s forests offer resources that benefit local communities and are sustainably managed for future generations.  

Making the grade: The careful process of choosing what wood is right for biomass

Key takeaways:

  • British Columbia’s working forests are owned by the province and managed  to preserve the environment while supporting forestry industries and local communities.
  • When forests are harvested, professional, licensed scalers who are independent of logging companies or sawmills, evaluate the size and quality of wood.
  • The processes and assessments made by scalers are extensive and designed to ensure high quality lumber makes its way to commercial markets.
  • The careful process of grading wood ensures that only low-quality wood, unusable by lumber sectors is used to produce sustainable biomass pellets.

Healthy working forests are full of different species of trees that serve as essential commercial resource to rural communities. Within these forests are different qualities of wood and trees.

The lumber industry, which drives the commercial forestry in British Columbia, only uses high-quality sawlogs that can be processed into lumber and other valuable solid wood products. When forest companies and the provincial government identify areas of forest suitable for management, the materials are professionally, independently sorted, and selected by the logging operator according to specifications set by the sawmill and by merchantability specifications set by government.


This leaves a range of rejected roundwood trees and other materials that are unsuitable for lumber. Characteristics of rejected material can include undersized logs, rotting in parts, excessive twisting, cracks, large knots, or exposure to damage like fires. But that’s not to say the wood isn’t valuable.

The biomass industry emerged as a way to utilise wood and residues from forestry and sawmill processes. To sort through wood harvests and identify what wood is suitable for lumber, forest companies in British Columbia use a grading system.

The province’s Forest Act outlines that timber harvested from publicly owned Crown must be scaled (measured) and graded. This standardised system means all types of wood are utilised, and the full value of a harvest maximised for lumber and other wood products – ensuring forests remain valuable resources that are replanted and managed for future generations.

Making the grade

The policy of scaling and grading timber has been in action along British Columbia’s coastal forests since as long ago as 1902.  And while log grades have evolved and expanded with changes in wood utilisation and forest practices, today’s grading rules and conventions are very similar to those used more than a century ago. 

Timber scaling and grading can only be carried out by trained, licenced professionals, known as scalers. The processes and assessments they are required to carry out are rigorous and extensive, as outlined in a regularly updated Scaling Manual.

Scalers apply grading rules to determine: the log’s gross dimensions, estimate what portion of the log is available to produce a given product, and consider the quality of the product that could be produced from the log.

It’s the scaler’s job to assess the visible characteristics of each log and determine what can be recovered from the log given its size and quality characteristics. Results in British Columbia are reported in cubic metres, with one cubic metre of timber viewed as a cubic metre of solid wood (known as firmwood), free of any rot, hole, char, or missing wood. It’s then up to the manufacturer to get the best and most valuable product out of the available volume.

Grade rules typically include three components: minimum or maximum dimensions, a requirement that a percentage of the log’s volume must be available to manufacture a given product, a requirement that a percentage of the product manufactured from the log must meet or exceed a given quality.

By developing methods of taking measurements in British Columbia’s coastal and interior regions, meaningful data is generated to understand the health and quality of the province’s diverse forests.

Click to view/download. 

Grade code 1 – Premium sawlogs

The highest-quality and most valuable grade, a grade code 1 log must be 2.5 m or more in length and 10 cm or more in radius. It can also be a slab of wood 2.5 m long and 20 cm wide and 20 cm or more in thickness measured at a right angle to the growth rings.

For species like hemlock, cedar or balsam log or slab, at least 90% of the overall log can be manufactured into lumber, meaning it’s free of rot, chars, or holes, without too many knots or twists.

For other species, at least 75% can be manufactured into lumber. For all species, at least 75% of the lumber will be suitable for sale.

Grade code 2 – Sawlog 

Smaller than premium sawlogs, grade code 2 logs are also 2.5 m or longer but can be only 5 cm wide. Grade code 2 sawlogs can also be made from slabs of wood 2.5 m or more in length and 15 cm wide, with a 15 cm or more thickness measured at a right angle to the growth rings.

In species like hemlock or cedar at least 75% of the wood can be manufactured into lumber, while for a balsam logs, it’s at least 67%. For all other species, at least 50% of overall wood can be manufactured into lumber.

Grade code 4 – Lumber reject

Lumber reject is the grade given to a log or slab that’s higher in grade than firmwood reject, but not high-grade enough to meet the requirements for a sawlog, due to factors like rot, chars, and holes.

The reason there is no grade code 3 or 5 is because they were merged into the lumber reject category as the needs of forestry industries changed.

Grade code 6 – Undersized log

An undersized log is the higher in grade than firmwood reject but cut from a tree which was below the minimum diameter to be processed into high-quality, useable lumber.

Grade code Z – Firmwood reject

The lowest grade of wood, a Grade code Z log is not of a high enough quality to be made into lumber.

A log falls into the firmwood reject category if there is heart rot or a hole that runs the entire length of the log, and any firmwood around the defect makes up less than 50% of the overall log.

A scaler may also grade a log as Z if rot is in the log and they estimate the net length of the log to be less than 1.2 m. Sap rot or charred wood within a log where the residual firmwood is less than 10 cm in diameter at the butt end of the log also makes it Grade code Z.

Portions of healthier logs that are less than 10 cm in diameter or portion of a slab that is less than 10 cm in thickness, are also in this category.

Supporting healthy, resilient forests

Wood that is unsuitable for valuable sawlogs was once seen as a residual of forestry harvest and burned as a means of disposal, emitting CO2, and polluting local air. The biomass market, however, processes low-grade wood into a feedstock for renewable electricity, unlocking the full value of forest resources, as well as enhancing ecosystems.

Slash pile in British Columbia

Newly developed forest management practises aimed at mitigating against wildfires, enhancing areas of habitats for wildlife, or restoring fire or diseased-damaged ecosystems, typically generate high volumes of low-grade wood. Without a local biomass market that can purchase and make use of that wood there’s less incentive to carry out these kinds of activities.

As wildfires and pests, like the mountain pine beetle, become increasing threats for Canadian forests and the rural communities who depend on them for work and leisure, the biomass sector’s participation is key to supporting forest management that ensures healthy, resilient forests.

Click to view/download.

The key to sustainable forests? Thinking globally and managing locally

Key takeaways:

  • Working forests, where wood products are harvested, are explicitly managed to balance environmental and economic benefits, while encouraging healthy, growing forests that store carbon, provide habitats for wildlife, and space for recreation.
  • But there is no single management technique. The most effective methods vary depending on local conditions.
  • By employing locally appropriate methods, working forests have grown while supporting essential forestry industries and local economies.
  • Forests in the U.S. South, British Columbia, and Estonia all demonstrate how local management can deliver both environmental and economic wins.

Forests are biological, environmental, and economic powerhouses. Collectively they are home to most of the planet’s terrestrial biodiversity. They are responsible for absorbing 7.6 billion tonnes of carbon dioxide (CO2) equivalent per year, or roughly 1.5 times the amount of CO2 produced by the United States on an annual basis. And working forests, which are actively managed to generate revenue from wood products industries, are important drivers for the global economy, employing over 13 million people worldwide and generating $600 billion annually.

But as important as forests are globally, the key to maximizing working forests’ potential lies in smart, active forest management. While 420 million hectares of forest have been lost since 1990 through conversion to other land uses such as for agriculture, many working forests are actually growing both larger and healthier due to science-based management practices.

The best practices in working forests balance economic, social, and environmental benefits. But just as importantly, they are tailored to local conditions and framed by appropriate regional regulations, guidance, and best-practice.

The following describes how three different regions, from which Drax sources its biomass, manage their forests for a sustainable future.

British Columbia: Managing locally for global climate change

British Columbia is blanketed by almost 60 million hectares of forest – an area larger than France and Germany combined. Over 90% of the forest land is owned by Canada’s government, meaning the province’s forests are managed for the benefit of the Canadian people and in collaboration with First Nations.

From the province’s expanse of forested land, less than half a percent (0.36%) is harvested each year, according to government figures. This ensures stable, sustainable forests. However, there’s a need to manage against natural factors.

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In 2017, 2018, and 2020 catastrophic fires ripped through some of British Columbia’s most iconic forest areas, underscoring the threat climate change poses to the area’s natural resources. One response was to increase the removal of stands of trees in the forest, harvesting the large number of dead or dying trees created by pests that have grown more common in a warming climate.

By removing dead trees, diseased trees, and even some healthy trees, forest managers can reduce the amount of potential fuel in the forest, making devastating wildfires less likely. There are also commercial advantages to this strategy. Most of the trees removed are low quality and not suitable for processing into lumber. These trees can, however, still be used commercially to produce biomass wood pellets that offer a renewable alternative to fossil fuels. This means local communities don’t just get safer forests, they get safer forests that support the local economy.

The United States: Thinning for healthier forests

The U.S. South’s forests have expanded rapidly in recent decades, largely due to growth in working forests on private land. Annual forest growth in the region more than doubled from 193 million cubic metres of wood in 1953 to 408 million cubic meters by 2015.

This expansion has occurred thanks to active forest product markets which incentivise forest management investment. In the southern U.S. thinning is critical to managing healthy and productive pine forests.

Thinning is an intermediate harvest aimed at reducing tree density to allocate more resources, like nutrients, sunlight, and water, to trees which will eventually become valuable sawtimber. Thinning not only increases future sawtimber yields, but also improves the forest’s resilience to pest, disease, and wildfire, as well as enhancing understory diversity and wildlife habitat.

Click to view/download

While trees removed during thinning are generally undersized or unsuitable for lumber, they’re ideal for producing biomass wood pellets. In this way, the biomass market creates an incentive for managers to engage in practices that increase the health and vigour of forests on their land.

The results speak for themselves: across U.S. forestland the volume of annual net timber growth 36% higher than the volume of annual timber removals.

A managed working forest in the US South

Estonia: Seeding the future

Though Estonia is not a large country, approximately half of it is covered in trees, meaning forestry is integral to the country’s way of life. Historically, harvesting trees has been an important part of the national economy, and the government has established strict laws to ensure sustainable management practices.

These regulations have helped Estonia increase its overall forest cover from about 34% 80 years ago to over 50% today. And, as in the U.S. South, the volume of wood harvested from Estonia’s forests each year is less than the volume added by tree growth.

Sunrise and fog over forest landscape in Estonia

Sunrise and fog over forest landscape in Estonia

Estonia has managed to increase its growing forest stock by letting the average age of its forests increase. This is partially due to Estonia having young, fast-growing forests in areas where tree growth is relatively new. But it is also due to regulations that require harvesters to leave seed trees.

Seed trees are healthy, mature trees, the seeds from which become the forest’s next generation. By enforcing laws that ensure seed trees are not harvested, Estonia is encouraging natural regeneration of forests. As in the U.S. South protecting these seed trees from competition for water and nutrients means removing smaller trees in the area. While these smaller trees may not all be suitable for lumber, they are a suitable feedstock for biomass. It means managing for natural regeneration can still have economic, as well as environmental, advantages.

Different methods, similar results

Laws, landownership, and forestry practices differ greatly between the U.S. South, British Columbia, and Estonia, but all three are excellent examples of how local forest management contributes to healthy rural economies and sustained forest coverage.

While there are many different strategies for creating a balance between economic and environmental interests, all successful strategies have something in common: They encourage healthy, growing forests.

Supporting a circular economy in the forests

Every year in British Columbia, millions of tonnes of waste wood – known in the industry as slash – is burned by the side of the road.

Land managers are required by law to dispose of this waste wood – that includes leftover tree limbs and tops, and wood that is rotten, diseased and already fire damaged – to reduce the risks of wildfires and the spread of disease and pests.

The smoke from these fires is choking surrounding communities – sometimes “smoking out entire valleys,” air quality meteorologist from BC’s Environment Ministry Trina Orchard recently told iNFOnews.ca.

It also impacts the broader environment, releasing some 3 million tonnes of CO2 a year into the atmosphere, according to some early estimates.

Slash pile in British Columbia

Landfilling this waste material from logging operations isn’t an option as it would emit methane – a greenhouse gas that is about 25 times more potent than CO2. So you can see why it ends up being burned.

In its Modernizing Forest Policy in BC, the government has already identified its intention to phase out the burning of this waste wood left over after harvesting operations and is working with suppliers and other companies to encourage the use of this fibre.

This is a very positive move as this material must come out of the forests to reduce the fuel load that can help wildfires grow and spread to the point where they can’t be controlled, let alone be extinguished.

The wildfire risk is real and growing. Each year more forests and land are destroyed by wildfire, impacting communities, nature, wildlife and the environment.

In the past two decades, wildfires burned two and a half times more land in BC than in the previous 50-year period. According to very early estimates, emissions from last year’s wildfires in the province released around 150 million tonnes of CO2 – equivalent to around 30 million cars on the road for a year.

Alan Knight at the log yard for Lavington Pellet Mill in British Columbia

During my recent trip to British Columbia in Canada, First Nations, foresters, academics, scientists and government officials all talked about the burning piles of waste wood left over after logging operations.

Rather than burning it, it would be far better, they say, to use more of this potential resource as a feedstock for pellets that can be used to generate renewable energy, while supporting local jobs across the forestry sector and helping bolster the resilience of Canada’s forests against wildfire.

I like this approach because it brings pragmatism and common sense to the debate over Canada’s forests from the very people who know the most about the landscape around them.

Burning it at the roadside is a waste of a resource that could be put to much better use in generating renewable electricity, displacing fossil fuels, and it highlights the positive role the bioenergy industry can play in enhancing the forests and supporting communities.

Drax is already using some of this waste wood – which I saw in the log yard for our Lavington Pellet mill in British Columbia. This waste wood comprises around 20% of our feedstock. The remaining 80% comes from sawmill residues like sawdust, chips and shavings.

Waste wood for pellets at Lavington Pellet Mill log yard

It’s clear to me that using this waste material that has little other use or market value to make our pellets is an invaluable opportunity to deliver real benefits for communities, jobs and the environment while supporting a sustainable circular economy in the forestry sector.

What is the carbon cycle?

What is the carbon cycle?

All living things contain carbon and the carbon cycle is the process through which the element continuously moves from one place in nature to another. Most carbon is stored in rock and sediment, but it’s also found in soil, oceans, and the atmosphere, and is produced by all living organisms – including plants, animals, and humans.

Carbon atoms move between the atmosphere and various storage locations, also known as reservoirs, on Earth. They do this through mechanisms such as photosynthesis, the decomposition and respiration of living organisms, and the eruption of volcanoes.

As our planet is a closed system, the overall amount of carbon doesn’t change. However, the level of carbon stored in a particular reservoir, including the atmosphere, can and does change, as does the speed at which carbon moves from one reservoir to another.

What is the role of photosynthesis in the carbon cycle?

Carbon exists in many different forms, including the colourless and odourless gas that is carbon dioxide (CO2). During photosynthesis, plants absorb light energy from the sun, water through their roots, and CO2 from the air – converting them into oxygen and glucose.

The oxygen is then released back into the air, while the carbon is stored in glucose, and used for energy by the plant to feed its stem, branches, leaves, and roots. Plants also release CO2 into the atmosphere through respiration.

Animals – including humans – who consume plants similarly digest the glucose for energy purposes. The cells in the human body then break down the glucose, with CO2 emitted as a waste product as we exhale.

CO2 is also produced when plants and animals die and are broken down by organisms such as fungi and bacteria during decomposition.

What is the fast carbon cycle?

The natural process of plants and animals releasing CO2 into the atmosphere through respiration and decomposition and plants absorbing it via photosynthesis is known as the biogenic carbon cycle. Biogenic refers to something that is produced by or originates from a living organism. This cycle also incorporates CO2 absorbed and released by the world’s oceans.

The biogenic carbon cycle is also called the “fast” carbon cycle, as the carbon that circulates through it does so comparatively quickly. There are nevertheless substantial variations within this faster cycle. Reservoir turnover times – a measure of how long the carbon remains in one location – range from years for the atmosphere to decades through to millennia for major carbon sinks on land and in the ocean.

What is the slow carbon cycle?

In some circumstances, plant and animal remains can become fossilised. This process, which takes millions of years, eventually leads to the formation of fossil fuels. Coal comes from the remains of plants that have been transformed into sedimentary rock. And we get crude oil and natural gas from plankton that once fell to the ocean floor and was, over time, buried by sediment.

The rocks and sedimentary layers where coal, crude oil, and natural gas are found form part of what is known as the geological or slow carbon cycle. From this cycle, carbon is returned to the atmosphere through, for example, volcanic eruptions and the weathering of rocks. In the slow carbon cycle, reservoir turnover times exceed 10,000 years and can stretch to millions of years.

How do humans impact the carbon cycle?

Left to its own devices, Earth can keep CO2 levels balanced, with similar amounts of CO2 released into and absorbed from the air. Carbon stored in rocks and sediment would slowly be emitted over a long period of time. However, human activity has upset this natural equilibrium.

Burning fossil fuel releases carbon that’s been sequestered in geological formations for millions of years, transferring it from the slow to the fast (biogenic) carbon cycle. This influx of fossil carbon leads to excessive levels of atmospheric CO2, that the biogenic carbon cycle can’t cope with.

As a greenhouse gas that traps heat from the sun between the Earth and its atmosphere, CO2 is essential to human existence. Without CO2 and other greenhouse gases, the planet could become too cold to sustain life.

However, the drastic increase in atmospheric CO2 due to human activity means that too much heat is now retained between Earth and the atmosphere. This has led to a continued rise in the average global temperature, a development that is part of climate change.

Where does biomass fit into the carbon cycle?

One way to help reduce fossil carbon is to replace fossil fuels with renewable energy, including sustainably sourced biomass. Feedstock for biomass energy includes plant material, wood, and forest residue – organic matter that absorbs CO2 as part of the biogenic carbon cycle. When the biomass is combusted in energy or electricity generation, the biogenic carbon stored in the organic matter is released back into the atmosphere as CO2.

This is distinctly different from the fossil carbon released by oil, gas, and coal. The addition of carbon capture and storage to bioenergy – creating BECCS – means the biogenic carbon absorbed by the organic matter is captured and sequestered, permanently removing it from the atmosphere. By capturing CO2 and transporting it to geological formations – such as porous rocks – for permanent storage, BECCS moves CO2 from the fast to the slow carbon cycle.

This is the opposite of burning fossil fuels, which takes carbon out of geological formations (the slow carbon cycle) and emits it into the atmosphere (the fast carbon cycle). Because BECCS removes more carbon than it emits, it delivers negative emissions.

Fast facts

  • According to a 2019 study, human activity including the burning of fossil fuels releases between 40 and 100 times more carbon every year than all volcanic eruptions around the world.
  • In March 2021, the Mauna Loa Observatory in Hawaii reported that average CO2 in the atmosphere for that month was 14 parts per million. This was 50% higher than at the time of the Industrial Revolution (1750-1800).
  • There is an estimated 85 billion gigatonne (Gt) of carbon stored below the surface of the Earth. In comparison, just 43,500 Gt is stored on land, in oceans, and in the atmosphere.
  • Forests around the world are vital carbon sinks, absorbing around 7.6 million tonnes of CO2 every year.

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What is sustainable forest management?

Sustainable forest management is frequently defined in terms of providing a balance of social, environmental, and economic benefits, not just for today but for the future too. It might be seen as the practice of maintaining forests to ensure they remain healthy, absorb more carbon than they release, and can continue to be enjoyed and used by future generations.

To achieve this, foresters apply science, knowledge, and standards that help ensure forests continue to play an important role in the wellbeing of people and the planet.

Managed forests, also called working forests, fulfil a variety of environmental, social, and economic functions. These range from forests managed to attract certain desired wildlife species, to forests grown to provide saw timber and reoccurring revenue for landowners.

How are forests sustainably managed?

How forests are managed depends on landowner goals – managing for recreation and wildlife, focusing on maximising production of wood products, or both. Each forest requires management tailored to its owner’s or manager’s objectives.

There are many ways to manage forests to keep them healthy – there is no ‘one size fits all’ – but keeping track of how they are doing can be tricky. One alternative for monitoring forests is to use satellite imagery.

One common sustainable forestry practice is thinning, which involves periodically removing smaller, unhealthy, or diseased trees to enable stronger ones to thrive. Thinning reduces competition between trees for resources like sunlight and water, and it can also help promote biodiversity by creating more space for other forest flora.

The wood removed from forests through thinning is sometimes not high-quality enough to be used in industries such as construction or furniture. However, the biomass industry can use it to make compressed wood pellets; a feedstock for renewable source electricity.

By providing a market for low-quality wood, pellet production encourages landowners to carry out thinnings. This practice improves the health of the forest, and helps support better growth, greater carbon storage, and creates more valuable woodland.

Fast facts

What are the environmental benefits of sustainably managed forests?

Through their ability to act as carbon sinks, forests are an important part of meeting global climate goals like the Paris Agreement and the UK’s own target of reaching net zero emissions by 2050.

When managed effectively through thinning or active harvesting, and replanting and regeneration, forests can often sequester – or absorb and store – more carbon than forests that are left untouched, increasing productivity and improving planting material.

Harvesting trees before they reach an age when growth slows or plateaus can help prevent fire damage, pests, and disease, so timing of final cutting is important. Though the vast majority of timber from such cutting will go to other markets (construction, furniture etc) and secure higher prices from those markets, being able to sell lower quality wood for biomass provides the landowner with some extra revenue.

Sustainably managed forests also help achieve other environmental goals, such as sustaining biodiversity, protecting sensitive sites and providing clean air and water. Managed forests also have substantial water absorption capacity preventing flooding by slowing the flow of sudden downpours and helping to prevent nearby rivers and streams from overfilling.

Wood from working forests also help tackle climate change in that high-value wood from harvested trees can be used to make timber for the construction or furniture sectors. These wood products lock up carbon for extended periods of time, and the wood can be used at end-of life to displace fossil fuels. Using wood also means materials such as concrete, bricks or steel are not used, and these materials have a large carbon footprint compared to wood.

What are the socioeconomic benefits of sustainably managed forests?

There are also social and economic benefits to managing forests. Sustainably managed working forests make vital contributions both to people and to the planet.

The commercial use of wood in industries like furniture and construction drives revenue for landowners. This encourages landowners to continue to replant forests and manage them in a sustainable way that continues to deliver returns.

Healthy forests can also improve living standards for local communities for jobs and helping to address unemployment in rural regions. Managed forests can also improve access for recreation. On a larger scale, sustainable forestry can offer a valuable export for regions and nations and foster trade between countries.

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Forests, net zero and the science behind biomass

Tackling climate change and spurring a global transition to net zero emissions will require collaboration between science and industry. New technologies and decarbonisation methods must be rooted in scientific research and testing.

Drax has almost a decade of experience in using biomass as a renewable source of power. Over that time, our understanding around the effectiveness of bioenergy, its role in improving forest health and ability to deliver negative emissions, has accelerated.

Research from governments and global organisations, such as the UN’s Intergovernmental Panel on Climate Change (IPCC) increasingly highlight sustainably sourced biomass and bioenergy’s role in achieving net zero on a wide scale.

The European Commission has also highlighted biomass’ potential to provide a solution that delivers both renewable energy and healthy, sustainably managed forests.  Frans Timmermans, the executive vice-president of the European Commission in charge of the European Green Deal has emphasised it’s importance in bringing economies to net zero, saying: “without biomass, we’re not going to make it. We need biomass in the mix, but the right biomass in the mix.”

The role of biomass in a sustainable future

Moving away from fossil fuels means building an electricity system that is primarily based on renewables. Supporting wind and solar, by providing electricity at times of low sunlight or wind levels, will require flexible sources of generation, such as biomass, as well as other technologies like increased energy storage.

In the UK, the Climate Change Committee’s (CCC) Sixth Carbon Budget report lays out its Balanced Net Zero Pathway. In this lead scenario, the CCC says that bioenergy can reduce fossil emissions across the whole economy by 2 million tonnes of CO2 or equivalent emissions (MtCO2e) per year by 2035, increasing to 2.5 MtCO2e in 2045.

Foresters in working forest, Mississippi

Foresters in working forest, Mississippi

Biomass is also expected to play a crucial role in supplying biofuels and hydrogen production for sectors of the global economy that will continue to use fuel rather than electricity, such as aviation, shipping and industrial processes. The CCC’s Balanced Net Zero Pathway suggest that enough low-carbon hydrogen and bioenergy will be needed to deliver 425 TWh of non-electric power in 2050 – compared to the 1,000 TWh of power fossil fuels currently provide to industries today.

However, bioenergy can only be considered to be good for the climate if the biomass used comes from sustainably managed sources. Good forest management practises ensure that forests remain sustainable sources of woody biomass and effective carbon sinks.

A report co-authored by IPCC experts examines the scientific literature around the climate effects (principally CO2 abatement) of sourcing biomass for bioenergy from forests managed according to sustainable forest management principles and practices.

The report highlights the dual impact managed forests contribute to climate change mitigation by providing material for forest products, including biomass that replace greenhouse gas (GHG)-intensive fossil fuels, and by storing carbon in forests and in long-lived forest products.

The role of biomass and bioenergy in decarbonising economies goes beyond just replacing fossil fuels. The addition of carbon capture and storage (CCS) to bioenergy to create bioenergy with carbon capture and storage (BECCS) enables renewable power generation while removing carbon from the atmosphere and carbon cycle permanently.

The negative emissions made possible by BECCS are now seen as a fundamental part of many scenarios to limit global warming to 1.5oC above pre-industrial levels.

BECCS and the path to net zero

The IPCC’s special report on limiting global warming to 1.5oC above pre-industrial levels, emphasises that even across a wide range of scenarios for energy systems, all share a substantial reliance on bioenergy – coupled with effective land-use that prevents it contributing to deforestation.

The second chapter of the report deals with pathways that can bring emissions down to zero by the mid-century. Bioenergy use is substantial in 1.5°C pathways with or without CCS due to its multiple roles in decarbonising both electricity generation and other industries that depend on fossil fuels.

However, it’s the negative emissions made possible by BECCS that make biomass  instrumental in multiple net zero scenarios. The IPCC report highlights BECCS alongside the associated afforestation and reforestation (AR), that comes with sustainable forest management, are key components in pathways that limit climate change to 1.5oC.

Graphic showing how BECCS removes carbon from the atmosphere. Click to view/download

There are two key factors that make BECCS and other forms of emissions removals so essential: The first is their ability to neutralise residual emissions from sources that are not reducing their emissions fast enough and those that are difficult or even impossible to fully decarbonise. Aviation and agriculture are two sectors vital to the global economy with hard-to-abate emissions. Negative emissions technologies can remove an equivalent amount of CO2 that these industries produce helping balance emissions and progressing economies towards net zero.

The second reason BECCS and other negative emissions technologies will be so important in the future is in the removal of historic CO2 emissions. What makes CO2 such an important GHG to reduce and remove is that it lasts much longer in the atmosphere than any other. To help reach the Paris Agreement’s goal of limiting temperature rises to below 1.5oC removing historic emissions from the atmosphere will be essential.

In the UK, the  CCC’s 2018 report ‘Biomass in a low-carbon economy’ also points to BECCS as both a crucial source of energy and emissions abatement.

It suggests that power generation from BECCS will increase from 3 TWh per year in 2035 to 45 TWh per year in 2050. It marks a sharp increase from the 19.5 TWh that biomass (without CCS) accounted for across 2020, according to Electric Insights data. It also suggests that BECCS could sequester 1.1 tonnes of CO2 for every tonne of biomass used, providing clear negative emissions.

However, the report makes clear that unlocking the potential of bioenergy and BECCS is only possible when biomass stocks are managed in a sustainable way that, as a minimum requirement, maintains the carbon stocks in plants and soils over time.

With increased attention paid to forest management and land use, there is a growing body of evidence that points to bioenergy as a win-win solution that can decarbonise power and economies, while supporting healthy forests that effectively sequester CO2.

How bioenergy ensures sustainable forests

Biomass used in electricity generation and other industries must come from sustainable sources to offer a renewable, climate beneficial [or low carbon] source of power.

UK legislation on biomass sourcing states that operators must maintain an adequate inventory of the trees in the area (including data on the growth of the trees and on the extraction of wood) to ensure that wood is extracted from the area at a rate that does not exceed its long-term capacity to produce wood. This is designed to ensure that areas where biomass is sourced from retain their productivity and ability to continue sequestering carbon.

Ensuring that forestland remains productive and protected from land-use changes, such as urban creep, where vegetated land is converted into urban, concreted spaces, depends on a healthy market for wood products. Industries such as construction and furniture offer higher prices for higher-quality wood. While low-quality, waste wood, as well as residues from forests and wood-industry by-products, can be bought and used to produce biomass pellets.

A report by Forest 2 Market examined the relationship between demand for wood and forests’ productivity and ability to sequester carbon in the US South, where Drax sources about two-thirds of its biomass.

The report found that increased demand for wood did not displace forests in the US South. Instead, it encouraged landowners to invest in productivity improvements that increased the amount of wood fibre and therefore carbon contained in the region’s forests.

A synthesis report, which examines a broad range of research papers,  published in Forest Ecology and Management in March of 2021, concluded from existing studies that claims of large-scale damage to biodiversity from woody biofuel in the South East US are not supported. The use of these forest residues as an energy source was also found to lead to net GHG greenhouse emissions savings compared to fossil fuels, according to Forest Research.

Importantly the research shows that climate risks are not exacerbated because of biomass sourcing; in fact, the opposite is true with annual wood growth in the US South increasing by 112% between 1953 and 2015.

Delivering a “win-win solution”

The European Commission’s JRC Science for Policy literature review and knowledge synthesis report ‘The use of woody biomass for energy production in the EU’ suggests  a win-win forest bioenergy pathway is possible, that can reduce greenhouse gas emissions in the short term, while at the same time not damaging, or even improving, the condition of forest ecosystems.

However, it also makes clear “lose-lose” situations is also a possible, in which forest ecosystems are damaged without providing carbon emission reductions in policy-relevant timeframes.

Win-win management practices must benefit climate change mitigation and have either a neutral or positive effect on biodiversity. A win-win future would see the afforestation of former arable land with diverse and naturally regenerated forests.

The report also warns of trade-offs between local biodiversity and mitigating carbon emissions, or vice versa. These must be carefully navigated to avoid creating a lose-lose scenario where biodiversity is damaged and natural forests are converted into plantations, while BECCS fails to deliver the necessary negative emissions.

In a future that will depend on science working in collaboration with industries to build a net zero future continued research is key to ensuring biomass can deliver the win-win solution of renewable electricity with negative emissions while supporting healthy forests.

Evaluating regrowth post-harvest with accurate data and satellite imagery

  • Drax has been using effective post-harvest evaluations, which includes remote sensing technology and satellite imagery

  • Alongside sustainable forest management, monitoring can help support rapid regrowth after harvesting

  • Evidence shows healthy managed forests with no signs of deforestation or degradation

As part of Drax’s world-leading programme of demonstrating biomass sustainability, including ongoing work on catchment area analysis (CAA), responsible sourcing policy and healthy forest landscapes (HFL). We have also been trialling the use of high-resolution satellite imagery to monitor forest conditions on specific harvesting sites in the years after harvesting has taken place, in addition to the catchment area level monitoring of trends and data. Post-harvest evaluations (PHE) are an essential part of an ongoing sustainability monitoring process, ensuring that the future forest resource is protected and maintained and that landowners restore forests after harvesting to prevent deforestation or degradation.

The most effective form of PHE is for an experienced local forester to walk and survey the harvesting site to check that new trees are growing and that the health and quality of the young replacement forest is maintained.

Rapid regrowth

The images below show some of the sites surrounding Drax’s Amite Bioenergy pellet plant in Mississippi, with trees at various stages of regrowth in the years after harvesting.

A full site inspection can therefore enable a forester to determine whether the quantity and distribution of healthy trees is sufficient to make a productive forest, equivalent to the area that was harvested. It can also identify if there are any health problems, pest damage or management issues such as  weed growth or water-logging that should be resolved.

Typically, this will be the responsibility of the forest owner or their forest manager and is a regular part of ongoing forest management activity. This degree of survey and assessment is not practical or cost-effective where a third-party consumer of wood fibre purchases a small proportion (typically 20-25 tonnes per acre) of the low-grade fibre produced at a harvest as a one-off transaction for its wood pellet plant..  It is time consuming to walk every acre of restocked forest and it is not always possible to get an owner’s permission to access their land.

Forests from space

Therefore, an alternative methodology is required to make an assessment about the condition of forest lands that have been harvested to supply biomass, without the need to physically inspect each site.  One option is to use remote sensing and satellite imagery to view each harvested site in the years after biomass sourcing, this helps to monitor restocking and new tree growth.

Drax has been testing the remote sensing approach using Maxar’s commercial satellite imagery.  Maxar has four satellites on orbit that collect more than three million square kilometres of high-resolution imagery every day. Drax accesses this imagery through Maxar’s subscription service SecureWatch.

To test the viability of this methodology, Drax has been looking at harvesting sites in Mississippi that supplied biomass to the Amite Bioenergy pellet plant in 2015 and in 2017.  As part of the sustainability checks that are carried out prior to purchasing wood fibre, Drax collects information on each harvesting tract. This includes the location of the site, the type of harvest, the owner’s long-term management intentions and species and volume details.

This data can then be used at a later date to revisit the site and monitor the condition of the area. Third-party auditors, for instance Through Sustainable Biomass Program (SBP) certification, do visit harvesting sites, however this is typically during the year of harvest rather than after restocking. Maxar has historical imagery of this region from 2010, which is prior to any harvesting for wood pellets.  The image below shows a harvesting site near the pellet plant at Gloster, Mississippi, before any harvesting has taken place.

March 2010 (100m)

Satellite image © 2021 Maxar Technologies.

The image below shows the same site in 2017 immediately following harvesting.

December 2017 (100m)

Satellite image © 2021 Maxar Technologies.

If we look again at this same site three years after harvesting, we can see the rows of trees that have been planted and the quality of the regrowth. This series of images demonstrates that this harvested area has remained a forest, has not been subject to deforestation and that the regrowth appears to be healthy at this stage.

August 2020 (50m)

Satellite image © 2021 Maxar Technologies.

Another site in the Amite catchment area is shown below. The image shows a mature forest prior to harvesting, the site has been previously thinned as can be seen from the thinned rows that are evident in the imagery.

May 2010 (200m)

Satellite image © 2021 Maxar Technologies.

Looking at the same site in the year after harvesting, the clear cut area can be seen clearly. Some green vegetation cover can also be seen on the harvested area, but this is weed growth rather than replanted trees. Some areas of mature trees have been left at the time of harvesting, and are visible as a grey colour in the 2010 image. These are likely to be streamside management zones that have been left to maintain biodiversity and to protect water quality, with the grey winter colouring suggesting that they are hardwoods.

September 2018 (200m)

Satellite image © 2021 Maxar Technologies.

Three years after the harvest, in a zoomed in view from the previous image, clear rows of replanted trees can be seen in the imagery.  This demonstrates that the owner has successfully restocked the forest area and that the newly planted forest appears healthy and well established.

August 2020 (50m)

Satellite image © 2021 Maxar Technologies.

While examining different harvesting sites in satellite imagery, Drax noted that not every site had evidence of tree growth, particularly within the first three years after harvesting. Deliberate conversion of land to non-forest use, such as for conversion to pasture, agricultural crops or urban development, is likely to be evident fairly soon after harvesting.

Preparing for planting

Some forest owners like to leave a harvested site unplanted for a couple of years to allow ground vegetation and weed growth to establish, this can then be treated to ensure that trees can be planted and that the weed growth does not impede the establishment of the new forest, this process can mean that trees are not visible in satellite imagery for three to four years after harvesting.

The image below shows a site three years after harvesting with no evidence of tree growth.  Given that no conversion of land use is evident and that the site appears to be clear of weed growth, this is likely to be an example of where the owners have waited to clear the site of weeds prior to replanting.  This site can be monitored in future imagery from the Maxar satellites to ensure that forest regrowth does take place.

November 2020 (100m)

Satellite image © 2021 Maxar Technologies.

Drax will continue to use Maxar’s SecureWatch platform to monitor the regrowth of harvesting sites and will publish more detailed results and analysis when this process has been developed further.  The platform allows ongoing comparison of a site over time and could prove a more efficient method of analysis than ground survey.  In conjunction with the CAA and HFL work, PHE can add remote sensing as a valuable monitoring and evidence-gathering tool to demonstrate robust biomass sustainability standards and a positive environmental impact.

Go deeper: 

Discover the steps we take to ensure our wood pellet supply chain is better for our forests, our planet and our future here, how to plant more trees and better manage them, our responsible sourcing policy for biomass from sustainable forests and a guide to sustainable forest management of the Southern Working Forest.