7 Most Sustainable Hardwoods: A Life-Cycle Analysis

7 Most Sustainable Hardwoods: A Life-Cycle Analysis

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Quynh Nguyen

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Woods are generally a sustainable material thanks to carbon sequestration. However, the environmental impacts vary when different hardwood trees are cut down and when their timber is transported to places to be turned into a product. Besides, some hardwood trees provide vital shelter and food sources for animals, birds, and insects. So we have to ask: Which hardwoods are the most sustainable option to use in our wood projects? 

The most sustainable hardwoods come from tulip, black cherry, willow, aspen, elm, cottonwood, and soft maple trees. On top of their carbon sequestration potential, these timber trees are fast-growing species that are abundant in US forests. Their wood is also fast to dry and light to transport.

In this article, we’ll walk you through the life-cycle of the seven most sustainable hardwoods commonly used in woodworking. Then, we evaluate its sustainability, potential, and shortfalls. And in the end, we’ll show you tips for buying sustainable hardwoods.

Here’s How We Assessed the Sustainability of All Types of Hardwoods

In general, hardwoods are a sustainable material because of timber trees’ carbon sequestration potential and the carbon offset value at the end of the hardwood product. 

Sustainable: The ability to be maintained at a certain rate or level | Avoidance of the depletion of natural resources in order to maintain an ecological balance”

Oxford Dictionary

However, some hardwoods are more sustainable than others. One way of assessing the sustainability of hardwood is to go through the life-cycles of wood products and assess each stage’s sustainability. This life-cycle assessment (LCA) is a method to evaluate the environmental impacts of products and materials. Over the years, companies have strategically used LCA to research and create more sustainable products. So, let’s have a look at the LCA of some most sustainable hardwoods!

In this article, we’ll use the cradle-to-grave perspective of the LCA, examining the five stages of the life-cycle of hardwoods. Where it is relevant, we also use data from cradle-to-gate assessments

These five stages of the life-cycle of hardwood are as follows:

  1. Growing of each hardwood
  2. Manufacturing of each hardwood
  3. Transportation of each hardwood
  4. Usage of each hardwood
  5. End-of-life of each hardwood

The life-cycle assessment typically covers some or all of the following environmental impacts:

  • Global warming potential 
  • Primary energy demand from resources 
  • Acidification potential
  • Freshwater eutrophication potential 
  • Marine eutrophication potential 
  • Photochemical ozone creation potential 
  • Resource depletion

The global warming potential impact reflects the risk of accelerating climate change through the emissions of greenhouse gases. It focuses CO2 and other greenhouse gasses (CH4, nitrous oxide, and chlorofluorocarbons) released throughout a product’s life-cycle. This impact is measured in kg of CO2 equivalent emitted per unit of a product, or the carbon footprint. 

Carbon footprint: the amount of greenhouse gases and specifically carbon dioxide emitted by something (such as a person’s activities or a product’s manufacture and transport) during a given period”

Merriam Webster

In this article, we cover seven hardwoods with the lowest carbon emissions. We’ll zoom into factors like species’ growth rate, tree size, distribution, and relevant woodworking properties, as these are often the reasons behind lower carbon footprints. 

These Are the Seven Most Sustainable Types of Hardwoods

These woods have the lowest carbon emissions on a life-cycle assessment basis. As timber, they all store carbon throughout their life cycles. 

Type of Wood Overall Sustainability
Tulipwood Carbon footprint: The carbon footprint of tulip poplar or American tulipwood (1 m3 of kiln-dried, 1-inch thick log) is 270 kg CO2-eq – the lowest in all US hardwoods available on a commercial scale.

Additionally: Tulipwood’s low weight and fast-drying property help to reduce fuel and energy consumption during harvesting, manufacturing, and transporting. Tulip trees grow rapidly to a large size, replenishing any timber cut for furniture at a fast rate.
Black cherry wood  Carbon footprint: Back cherry wood has a carbon footprint of 301 kg CO2-eq, cradle-to-gate. That is lower than all US-native hardwoods of similar density and strength.

Additionally: Black cherry (or American cherry) wood is a very sustainable hardwood because of the durability of the timber and the fast rate at which the cut wood is replaced in the wild. 
Willow wood Carbon footprint: Willow wood has a low carbon footprint of 310 kg CO2-eq for 1m3 of kiln-dried, 1-inch thick log.

Additionally: Willow timber is sustainable because they are light to transport and fast to replace. These tree species are also valuable for quick reforestation of certain sites where other trees don’t grow.
Aspen wood Carbon footprint: Aspen has a carbon footprint of 325 kg CO2-eq per one cubic meter of kiln-dried. However, compared with commonly used US hardwoods, this carbon footprint is on the low-end spectrum.

Additionally: Aspen wood is highly sustainable because of these trees’ carbon sequestration potential. In addition to their impressive height and diameter, aspen trees can regrow easily after timber harvesting. The wide distribution and the ease of regeneration make it possible to cut down the trees without harming the forests.
Elm wood Carbon footprint: Elm wood has a low carbon footprint of 357 kg CO2-eq per cubic meter of kiln-dried, 4/4 lumber. Low emissions are a combined result of the fast-drying property and the low weight.

Additionally: American elm is the survivor of the Dutch elm disease that has killed off most elm trees worldwide, thanks to the species’ prolific seed production and fast growth. The timber is light yet strong, making it sustainable in transporting and usage.
Cottonwood Carbon footprint: The carbon footprint of cottonwood (the largest species of all poplar wood) is 373 kg CO2-eq for one cubic meter of kiln-dried, 4/4 lumber. Though it is higher than some other poplar species, it is still in the low spectrum on the US hardwood scale.

Additionally: American eastern cottonwood is highly available because these fast-growing trees grow widely across the US. The light, porous wood has a very low drying carbon footprint and, consequently, an overall small carbon footprint.
Soft maple wood  Carbon footprint: Soft maple has a carbon footprint of 390 kg CO2-eq, which is higher than many other softer and lighter hardwoods. Yet, it is still one of the most prolific and sustainable hardwood species.

Additionally: Soft maple trees grow in abundance throughout the US forests. It is a very sustainable material thanks to the large growing stock, the fast-drying nature, and the durability of the timber.

Overall, these hardwoods are highly sustainable. However, the actual environmental impact of a particular product, be it a piece of furniture or flooring, depends on many factors, especially the distance and mode of transportation. Let’s dive deeper into each hardwood and the stages of its life-cycle and find out how it can be more sustainable. 

Tulipwood: Highly Sustainable Timber from One of US Tallest Hardwood Trees

The carbon footprint of tulip poplar or American tulipwood (1 m3 of kiln-dried, 1-inch thick log) is 270 kg CO2-eq – the lowest in all US hardwoods available on a commercial scale. 

Here are the life-cycle stages of American tulipwood and each stage’s sustainability assessment:

  • Growing of American tulipwood: Tulip trees (also called yellow poplar or tulip poplar) grow to a large size in a short time, sequestering carbon and helping to mitigate the climate crisis. Because of the abundance of these very tall hardwood trees in the US forests, it only takes 1.82 seconds to grow 1m3 of American tulipwood
  • Manufacturing of American tulipwood: The carbon footprint of drying tulipwood (one cubic meter, 1-inch thickness) is 25.6 kg CO2-eq, lower than all commonly-traded US hardwoods. This is due to the rapid drying speed. 
  • Transportation of American tulipwood: Tulipwood is lightweight and thus, less fuel-consuming during transportation. It has the lowest transporting carbon footprint of commercial US hardwoods
  • Usage of American tulipwood: With the right finishes, tulipwood furniture can be moderately durable, lasting up to a decade.
  • End-of-life of American tulipwood: Tulipwood furniture can be up-cycle to lengthen the carbon storage role or burned for biomass energy displacing coal or natural gas in generating electricity. 

Tulipwood’s low weight and fast-drying property help to reduce fuel and energy consumption during harvesting, manufacturing, and transporting. Tulip trees grow rapidly to a large size, replenishing any timber cut for furniture at a fast rate.

Black Cherry Wood: Durable Hardwood from Fast-Growing Trees 

Back cherry wood has a carbon footprint of 301 kg CO2-eq, cradle-to-gate. That is lower than all US-native hardwoods of similar density and strength.

Here are the life-cycle stages of black cherry wood and each stage’s sustainability assessment:

  • Growing of black cherry wood: Black cherry trees grow at fast rates of 2 to 4 feet per year. They act as a carbon sink during their long lifespan, helping to mitigate the climate crisis. 
  • Manufacturing of black cherry wood: Kiln drying 1-inch-thick black cherry lumber takes up to 120 hours and has a relatively low carbon footprint of 42.7 kg CO2-eq. Manufacturing carbon emission of black cherry is similar to willow wood and smaller than many other dense hardwoods like hard maple, hickory, red oak, and white oak
  • Transportation of black cherry wood: Black cherry grows abundantly in the wild throughout the US, resulting in a lower transporting carbon footprint. Thus, it is a sustainable alternative to imported tropical woods like mahogany
  • Usage of black cherry wood: Black cherry furniture is long-lasting carbon storage because the wood is resistant to decay and weather changes. Regarding usage, it is a very sustainable option, more so than hardwoods like maple.
  • End-of-life of black cherry wood: The end-of-life stage for black cherry furniture is sustainable when the wood is reused or burned as bioenergy.

Black cherry (or American cherry) wood is a very sustainable hardwood because of the durability of the timber and the fast rate at which the cut wood is replaced in the wild. 

Willow Wood: A Light Wood With Low Transporting Carbon Footprint 

Willow wood has a low carbon footprint of 310 kg CO2-eq for 1m3 of kiln-dried, 1-inch thick log. 

Here are the life-cycle stages of willow wood and each stage’s sustainability assessment:

  • Growing of willow wood: Willow trees regrow easily from cutting (or after a fire), enabling reforestation of disturbed sites. The fast-growing rate of willow trees indicates these species’ high potential for carbon sequestration and a positive role in mitigating climate change
  • Manufacturing of willow wood: Because willow wood dries rapidly, kiln-drying has a relatively low carbon footprint of 42.7 kg CO2-eq (1 m3 of 1-inch-thick logs). 
  • Transportation of willow wood: Willow wood is very light. Therefore, the carbon footprint of transporting 1m3 of willow lumber from forest to kiln is small (37.9 kg CO2-eq) – smaller than any other commonly-traded US hardwoods. 
  • Usage of willow wood: Willow furniture can last for a long time – up to a century – when being cared for properly indoors where there is no risk of insect attacks. 
  • End-of-life of willow wood: Willow furniture can either be up-cycled to lengthen the carbon storage role or burned biomass energy displacing coal or natural gas to generate electricity. 

Willow timber is sustainable because they are light to transport and fast to replace. These tree species are also valuable for quick reforestation of certain sites where other trees don’t grow.

Aspen Wood: Highly Available Timber from Easy-to-Grow Trees 

Aspen has a carbon footprint of 325 kg CO2-eq per one cubic meter of kiln-dried. However, compared with commonly used US hardwoods, this carbon footprint is on the low-end spectrum.

Here are the life-cycle stages of aspen wood and each stage’s sustainability assessment:

  • Growing of aspen wood: The fast-growing aspen trees grow in great numbers in the US forests (4.3% of US hardwood growing stock). Thus, it takes just over 6 seconds to grow 1m³ of American aspen. Once cut, aspen trees can regrow vigorously both from seedlings and root suckers. 
  • Manufacturing of aspen wood: This poplar wood is a fast-drying hardwood. This property contributes to a low drying carbon footprint (38.5 kg CO2-eq for one cubic meter).
  • Transportation of aspen wood: Aspen has the widest natural range of all trees native to North America, shortening the transporting distances (and thus carbon footprint). The average forest-to-kiln transportation emission is 45.2 kg CO2-eq
  • Usage of aspen wood: Indoor aspen furniture can last more than a couple of decades, providing adequate care. It is a good way to keep carbon out of the atmosphere. 
  • End-of-life of aspen wood: The end-of-life stage for aspen furniture is sustainable when the wood is reused or burned as bioenergy. 

Aspen wood is highly sustainable because of these trees’ carbon sequestration potential. In addition to their impressive height and diameter, aspen trees can regrow easily after timber harvesting. The wide distribution and the ease of regeneration make it possible to cut down the trees without harming the forests.

Elm Wood: Light and Easy-to-Dry Timber from Prolific Seed Producing Species 

Elm wood has a low carbon footprint of 357 kg CO2-eq per cubic meter of kiln-dried, 4/4 lumber. Low emissions are a combined result of the fast-drying property and the low weight.

Here are the life-cycle stages of elm wood and each stage’s sustainability assessment:

  • Growing of elm wood: American elm is a prolific seed-producing species. This nature has helped the species to survive the Dutch elm disease that has killed off most elm trees worldwide. The many fast-growing seedlings bring about a steady stock of elm timber, making wood harvesting more sustainable. 
  • Manufacturing of elm wood: Elm timber dries well with minimum degradation. It has a drying carbon footprint of 38.5 kg CO2-eq (1 m3, 4/4 elm logs), similar to aspen and lower than many other commercial hardwoods, including oak (red and white), hickory, black cherry, and willow. 
  • Transportation of elm wood: The transporting carbon footprint of elm is on the low end, thanks to the wood being strong yet light. 
  • Usage of elm wood: Elm’s interlocked grain makes the timber fairly resistant to shock and splitting, despite being a soft hardwood. It produces durable furniture and furniture parts where there is a need for shock absorbency. 
  • End-of-life of elm wood: At the end of their life, elm furniture can be upcycled (making new items) or recycled for bioenergy. 

American elm is the survivor of the Dutch elm disease that has killed off most elm trees worldwide, thanks to the species’ prolific seed production and fast growth. The timber is light yet strong, making it sustainable in transporting and usage.

Cottonwood (the Largest Species of Poplar Wood): Sustainable Wood From One of US Largest Hardwood Species 

The carbon footprint of cottonwood (the largest species of all poplar wood) is 373 kg CO2-eq for one cubic meter of kiln-dried, 4/4 lumber. Though it is higher than some other poplar species, it is still in the low spectrum on the US hardwood scale.

Here are the life-cycle stages of cottonwood and each stage’s sustainability assessment:

  • Growing of cottonwood: Cottonwood trees have a very high carbon sequestration potential because of their large sizes. These poplar species are among the biggest hardwood trees in North America. 
  • Manufacturing of cottonwood: The drying carbon footprint of cottonwood (1 m3, 1-inch logs) is 34.4 kg CO2-eq. It is lower than the majority of commonly used hardwoods in the US. 
  • Transportation of cottonwood: Similar to other poplar woods, cottonwood is light and has a relatively low transporting footprint. 
  • Usage of cottonwood: Using cottonwood is sustainable thanks to carbon being stored in wood products. 
  • End-of-life of cottonwood: Cottonwood furniture can be sustainably disposed of at the end of its life: upcycling for another woodworking project, burning to produce bioenergy. If not being disposed of, cottonwood products could end up in landfills, don’t decompose, and keep the role of carbon storage 

American eastern cottonwood is highly available because these fast-growing trees grow widely across the US. The light, porous wood has a very low drying carbon footprint and, consequently, an overall small carbon footprint.

Soft Maple Wood: Durable Hardwood from Highly Sustainably Managed Stock 

Soft maple has a carbon footprint of 390 kg CO2-eq, which is higher than many other softer and lighter hardwoods. Yet, it is still one of the most prolific and sustainable hardwood species.

Here are the life-cycle stages of soft maple wood and each stage’s sustainability assessment:

  • Growing of soft maple wood: Because of the large population of soft maple trees in the US, it takes merely 1.73 seconds to grow 1m³ of American soft maple. Though soft maples aren’t rapid-growing trees, such a growing stock – 11.1% of total US hardwood growing stock – allows harvesting timber without harming the forests. 
  • Manufacturing of soft maple wood: Soft maple has a very low drying carbon footprint for hardwood of such hardness and density. Kiln-drying one cubic meter of 1-inch soft maple logs emits 29.9 kg CO2-eq
  • Transportation of soft maple wood: Because soft maples are widely distributed in the eastern part of the US, it is possible to source this timber at relatively short transporting distances. These species have a lower transportation footprint than imported hardwoods of similar density and strength. 
  • Usage of soft maple wood: Maple is one of the most durable hardwood species in the US. It is, thus, an environmentally friendly material because the longer a piece of furniture lasts, the more sustainable it is in using the furniture as carbon storage. 
  • End-of-life of soft maple wood: The end-of-life stage for maple furniture is sustainable when the wood can be reused for another woodworking project or burned as bioenergy. 

Soft maple trees grow in abundance throughout the US forests. It is a very sustainable material thanks to the large growing stock, the fast-drying nature, and the durability of the timber.

How Can You Buy More Sustainable Hardwood

The key to sustainably buying any wood is to check on relevant environmental and original certifications. Reliable certifications for sustainable woods are: 

An FSC certification ensures that the wood comes from responsibly managed forests that provide environmental, social, and economic benefits.

PEFC’s approaches to sustainable forest management are in line with protecting the forests globally and locally and making the certificate work for everyone. Getting a PEFC certification is strict enough to ensure the sustainable management of a forest is socially just, ecologically sound, and economically viable but attainable not only by big but small forest owners. 

Why Is It Important to Buy More Sustainable Wood

Improperly managed logging (including illegal activities) can cause many problems for forest equality and diversity. One example is when loggers only cut down the biggest and tallest trees. That pattern would cause a reduction in the genetic diversity and quality of the trees within the stand, leading to gradual degradation of tree quality. 

In total, logging of forestry products from plantations accounts for 26% of forest loss, which is a combination of deforestation and forest degradation. However, the loss in bio-diverse forests in tropical climates is more significant (and sometimes less properly recorded) than in temperate, well-managed logging forests. 

Illustration of long-term forest loss
Our World in Data: Decadal losses in global forest over the last three centuries

Buying sustainable wood also means helping to prevent illegal or unsustainable logging, which harms the forests’ biosystems and accelerates climate change. 

Logging of forestry products from plantations accounts for 26% of forest loss. Cutting down trees for wood has a lesser impact on carbon storage than digging up the whole forest floor and turning it into farms or mines. However, if logging is not sustainably managed, it can badly damage wildlife.

When logging happens in tropical forests – the bio hotspots of our planet – the biodiversity loss can be much more damaging. Subtropical and tropical forests are packed with unique wildlife – endemic mammals, birds, and amphibians. The displacement of such wildlife during poorly managed logging would be a major contributor to global biodiversity loss. 

Sustainable management of forests also means that trees are cut down for timber only when they are mature. These trees will then be able to regrow and eventually replace the loss of canopy, absorb carbon from the atmosphere and reduce the effect of climate change.

Illustration of drivers of tropical forest degradation
Our World in Data: Drivers of tropical forest degradation

Final Thoughts

You can buy sustainable furniture made from hardwood as long as the material comes from sustainably managed forests. These seven hardwoods – tulip poplar, black cherry, willow, aspen, cottonwood, and soft maple – are among the most sustainable hardwoods in the US. It is thanks to the relatively low carbon emissions during harvesting, manufacturing, and transporting. You can make it even more sustainable by using furniture or household items made with these woods for as long as possible. Then, look into upcycling the material to extend its usage and/or arrange for it to be recycled fully.

Stay impactful,



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Quynh Nguyen

Quynh loves to research and write about how we can live more sustainably. Before joining Impactful Ninja, she managed communications at the social enterprise Fargreen. And when she's not writing, she likes to run in the woods, dig in the garden, or knit the next jumper.

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