Wood is generally a sustainable material, largely thanks to carbon uptake by timber trees. However, when demands have led to the overexploitation of a certain type of wood, the sustainability of the timber becomes questionable. So, we have to ask: Which types of wood are the least sustainable?

The 10 least sustainable woods come from ramin, rosewood, ebony, mahogany, brazilwood, lignum vitae, meranti, wenge, merbau, and sapele tree species. As these timber trees are overexploited, they cause an often-unrecoverable reduction in population and the biodiversity loss of their native forests. 

In this article, we will walk you through the life-cycle of the ten least sustainable types of wood. Then, we will evaluate their shortfalls and potential for being more sustainable. And in the end, we’ll show you tips for buying sustainable wood.

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

In general, wood is a sustainable material because of timber trees’ carbon sequestration potential and the carbon offset value at the end of the wood product’s life-cycle. However, overexploitation and illegal logging have made some types of wood much less sustainable than others. 

It is important to note that wood is generally better for the environment than plastic, provided that it is sourced from sustainably managed forests.

“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, the sustainability of harvesting wood from trees varies. One way to assess the sustainability of timber used in various applications is to go through their life-cycles and evaluate each stage’s sustainability. This life-cycle assessment (LCA) is a method to assess 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 look at the LCA of the 10 most sustainable types of wood.

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

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

1. Growing the trees for timber
2. Timber production 
3. Timber transportation 
4. Usage of wood
5. End-of-life of wood 

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 on 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—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

Deciding factors for a high or low carbon footprint in wood are: 

• drying requirements of wooden planks
• distribution of timber trees 

Because of the tree’s carbon sequestration potential, the carbon emitted during various stages in the life-cycle of wood can be compensated by the carbon captured and stored. The deciding factors for high or low carbon storage in wood are:

• tree sizes, 
• tree growth rate, and
• natural durability. 

Specifically, we’ll zoom into species’ population, growth rate, distribution, woodworking properties, and natural durability, as these are the deciding reasons behind the carbon balance of wood. 

These Are the 10 Least Sustainable Types of Wood

These woods are among the least sustainable types of wood, largely because their population in the wild has been continuously reduced. The native forests of these species are biodiverse and unique, meaning illegal and unsustainable logging practices in such forests have high ecological costs. 

Overall, each of these woods is not very sustainable, mainly because of the ecological costs associated with the often-illegal logging of these woods. 

However, the actual environmental impact of using a piece of wood depends on many factors, including: 

• the sourcing of the wood, such as the forest management practices in place 
• the manufacturing process, especially the drying step
• the distance and mode of transportation

Let’s dive deeper into each type of wood and the stages of its life-cycle. We will also provide information about how these types of wood can be harvested and used more sustainably. 

Ramin Wood: A Vulnerable Timber Species From Incredibly Biodiverse Southeast Asian Rainforests 

Ramin wood comes from a similar-looking group of trees native to Southeast Asian rainforests. Illegal logging and over-harvesting seriously threaten the region’s forests, whose biodiversity is rich, unique, and thus highly significant to the world’s ecological systems. 

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

• Growing and harvesting ramin wood is unsustainable. This is largely due to the damage done to the natural habitats of ramie tree species, some of which are incredibly biodiverse.
  • Growing ramie wood trees—of which there are 31 species in the Gonystylus genus—in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, illegal logging and over-harvesting of ramin timber (with the dominant species being G. bancanus) have significant ecological costs.
  • Overexploitation has led to repeated population reductions of ramie timber tree species over several generations. Consequently, the entire Gonystylus genus has been put on CITES Appendix II, which is reserved for species at risk in the wild. The Red List of Threatened Species by the IUCN has also listed this genus as vulnerable. Even though much of the timber trade only covers 6 out of the 31 species, the difficulty in distinguishing one species from others leads to the entire group falling under restriction. 
  • Harvesting ramin wood timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter, leading to biodiversity loss. The ecological cost of biodiversity loss in ramin species’ native forests can be extremely high. For example, over-harvesting and illegal logging cause the degradation of peat swamp forests in Sumatra, Indonesia. Tropical peat swamp forests are a unique ecosystem that is most extensive in Southeast Asia. Sumatran peat swamp forests, in particular, host incredible biodiversity with impressive numbers of plant, bird, and mammal species. They are home to rare wild cats like the Sumatran tiger, Sunda clouded leopard, marbled cat, and flat-headed cat. Malayan sun bears are also fairly common. 
  • Illegal logging of ramie wood is a persistent problem within and between Indonesia and Malaysia, even with the CITES status in place for this group of trees. 
• Manufacturing ramin wood is not very sustainable. This is because ramin wood takes a long time to dry.
  • Kiln-drying ramie logs from the green stock can take up to two and a half days. This process is energy-intensive as the kiln temperatures are kept above 100^oF (from 130^oF to 180^oF depending on the process). 
  • However, wood waste can be recycled fully as by-products or biomass pellets to offset the carbon emissions during harvesting and processing. At least 90% of all thermal energy used for kiln drying in the US hardwood sector is derived from biomass. 
• The transportation of ramin is generally not sustainable. Because ramin wood in the US would have come a long way from Southeast Asian countries, transporting ramin wood has a relatively high carbon footprint, higher than regionally available wood, like maple or birch. 
• The usage of ramin wood is not very sustainable
  • Ramin wood is rated as nondurable to perishable regarding decay resistance. 
  • It is also susceptible to insect attacks. 
  • Thus, ramin wood doesn’t keep its carbon storage role as long as some other woods, including locally available softwoods and hardwoods. 
• The end-of-life of ramin wood is sustainable. The wood can be reused or burned as bioenergy.

Ramin wood is an imported tropical wood with a much higher transporting carbon footprint than hardwoods from US temperate forests as it travels all the way from Southeast Asia. Illegal logging and trafficking of this group of timber, especially from unmatched biodiverse rainforests, make ramin wood one of the least sustainable materials for woodworking projects. It is better to avoid ramin completely, considering that the timber is fairly perishable and can be replaced with locally available alternatives.

Ebony Wood: A Critically Endangered Timber Species With a Diminishing Natural Habitat 

Ebony wood is favored by many because of its unique colors, ranging from very dark to jet-black, and its durability. However, the high demand for this valuable hardwood drives illegal logging and overexploitation in tropical forests, causing great biodiversity loss. 

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

• Growing and harvesting ebony wood is unsustainable. This is largely due to the persisting population reductions of various ebony tree species.
  • Growing ebony wood trees in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, because of the high demand for ebony wood’s unique color and strength, various ebony tree species have faced intense over-harvesting and illegal logging. 
  • Overexploitation leads to rapid reductions in the population of various ebony species—the tree species of the Diospyros genus—putting them at risk of distinction. 
    • Ceylon Ebony has been exploited to the point of commercial extinction. 
    • Mun Ebony is on the Red List of Threatened Species by the IUCN as a critically endangered species. 
    • Madagascar Ebony is on CITES Appendix II, which is reserved for species that are at risk in the wild. 
    • The population deduction of ebony is intensified by these species’ slow growth. For example, the East African ebony species takes from 70 to 200 years to reach maturity. In comparison, a planted teak tree, for example, often reaches maturity in 60 years, and a wild teak tree in around 80 to 120 years.
  • Harvesting ebony wood timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter. For example, the fruits feed different monkeys and apes, while the leaves are food for big animals like elephants. 
  • Illegal logging and uncontrolled trading of ebony wood is an alarming problem in various countries, including Madagascar, Vietnam, Laos, and Indonesia.

• Manufacturing ebony wood is not very sustainable. This is because ebony wood takes several years to dry naturally, while kiln-drying is energy-intensive with a risk of cracking. However, wood waste can be recycled fully as by-products or biomass pellets to offset the carbon emissions during harvesting and processing. 
• The transportation of ebony wood is generally not sustainable. This stage has a relatively high carbon footprint because ebony wood in the US would have come a long way from Africa or Asia. The transporting carbon footprint of ebony is generally more elevated than regionally available wood, like Douglas fir or maple. 
• The usage of ebony wood is sustainable. Ebony can last a long time, maintaining its carbon storage role instead of releasing carbon dioxide into the atmosphere.
  • Ebony is exceptionally dense, hard, and durable. These species have a Janka hardness—the indicator showing how well a plank of wood will withstand dents, dings, and wear—of 3,000 lbf (Mun Ebony) and above. These numbers are higher than many other tropical hardwoods, such as rosewood or teak. In further comparison, the white oak, which is considered one of the hardest woods from temperate forests, has a Janka hardness of 1,350 lbf. 
  • Ebony wood also has high resistance to attack by termites and an incredible ability to resist any sort of rot.
• The end-of-life of ebony wood is sustainable. The wood can be reused or burned as bioenergy.

Ebony wood is an imported tropical wood with a much higher transporting carbon footprint than hardwoods from US temperate forests. The high level of ebony timber exploitation, illegal logging, and ill-controlled trading makes ebony one of the least sustainable timber materials. If you must choose ebony wood for your project, opt for reclaimed material or less vulnerable species with sustainability certifications like FSC or PEFC. 

Rosewood: An Endangered Timber Species From Highly Biodiverse Tropical Forests 

Rosewood is loved, famed, and sought after for its rich red color and strong, sweet smell close to the fragrance of roses. Various rosewood species are native to biodiverse tropical forests where timber logging has extreme ecological costs, especially when done unrestrictedly or illegally. 

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

• Growing and harvesting rosewood is unsustainable. This is largely due to the rapid reduction in the rosewood populations around the tropical forests.
  • Growing rosewood trees in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, because of the high demand for rosewood’s color and fragrance quality, these tree species have faced overexploitation and trafficking in most continents, countries, and forests where they grow. 
  • Overlogging and slow-to-medium growth rates lead to rapid population reductions to the point that some species are considered endangered (Burmese rosewood) or vulnerable (Brazilian, East Indian, Madagascar, Siamese rosewood, and cocobolo) on the Red List of Threatened Species by the IUCN. Brazilian rosewood, in particular, is on CITES Appendix I, which is reserved for species that are in the most danger and are considered to be threatened with extinction. 
  • Harvesting rosewood timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter. For example, in Madagascar, logging has devastating consequences on the ruffed lemurs nesting on tall rosewood trees. Lemurs are endemic to Madagascar—an island with more genetic information per surface unit than any other country in the world. Consequently, such damage is beyond the removal of rare tree species. 
  • Illegal logging of rosewood is an extremely serious problem. It is the most trafficked wildlife, far more than elephant ivory, rhino horns, and pangolin scales put together.

• Manufacturing rosewood is not very sustainable. This is because rosewood takes a long time to dry naturally, while kiln-drying is energy-intensive, with a high risk of splitting for some certain rosewood species. However, wood waste can be recycled fully as by-products or biomass pellets to offset the carbon emissions during harvesting and processing. 

• The transportation of rosewood is generally not sustainable This stage has a relatively high carbon footprint because rosewood in the US would have come a long way (anywhere from Central America to Southeast Asia), making the footprint higher than that of regionally available wood, like maple or white oak. 

• The usage of rosewood is sustainable
  • When dried adequately, rosewood can last a long time, maintaining its carbon storage role instead of releasing carbon dioxide into the atmosphere. 
  • Generally, rosewood—timber from the Dalbergia genus—has high resistance against rot and termite attack. 
  • Also, rosewood is among the hardest wood. The following are the Janka hardness—the indicator showing how well a plank of wood will withstand dents, dings, and wear—of some rosewood species. (Keep in mind that the indicator for mighty white oak of the temperate forests is 1,350 lbf.)
    • Brazilian Rosewood (or Dalbergia nigra), found in Brazil: 2,790 lbf 
    • Amazon Rosewood (or Dalbergia spruceana), found in Brazil, Venezuela, and Bolivia: 2,700 lbf 
    • Honduran Rosewood (or Dalbergia stevensonii), found in Belize (British Honduras): 2,200 lbf 
    • Burmese Rosewood (or Dalbergia oliveri), found in Myanmar and other Southeast Asian nations: 2,710 lbf
    • Siamese Rosewood (or Dalbergia cochinchinensis), found in Thailand, Cambodia, Vietnam, and Laos: 2,430 lbf 
    • East Indian Rosewood (or Dalbergia latifolia), found in India, Sri Lanka, and Indonesia: 2,440 lbf
    • Madagascar Rosewood (a few Dalbergia species), found in Madagascar: 2,720 lbf 

• The end-of-life of rosewood is sustainable. The wood can be reused or burned as bioenergy.

Rosewood is an imported tropical wood with a much higher transporting carbon footprint than hardwoods from US temperate forests. The extreme level of rosewood exploitation and trafficking makes this group of beautiful and fragrant woods one of the least sustainable timber materials. If you must choose rosewood for your project, opt for reclaimed material or less vulnerable species with sustainability certifications like FSC or PEFC. 

Mahogany Wood: Beautiful Furniture Material Long Overexploited 

Mahogany wood is the exotic beauty from the tropical dry and wet forests, some of which host the most diverse wildlife in the world. Harvesting mahogany wood from those forests has huge environmental costs because they are vital to the world’s biodiversity. 

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

• Growing and harvesting mahogany wood is unsustainable. This is largely due to the diminishing natural habitat of these timber species in the wild and the lack of biodiversity in commercial mahogany plantations.
  • Growing mahogany wood trees in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, because of the high demand for mahogany wood, especially in high-end furniture, various mahogany tree species have faced intense over-harvesting and illegal logging. 
  • Lax forest management and illegal logging for the highly-priced mahogany have caused a significant decrease in forests where these species grow naturally, putting them at risk of distinction. 
    • Cuban mahogany is an endangered species on the Red List of Threatened Species by the IUCN. 
    • Several genuine mahogany species (of the genus Swietenia) and the African mahogany (of the genus Khaya)—are on CITES Appendix II, which is reserved for species that are at risk in the wild. 
    • A 2004 study has found that Bolivia no longer has commercially viable mahogany across 79% of its range, while Peru’s mahogany native habitat has halved. 
  • Harvesting mahogany wood timber unsustainably—illegally and/or in excess numbers in their native forests—disrupts wild animals, which depend on the forest for food and shelter. 
  • Because of the ban on mahogany exports from South America, these species are increasingly planted in monocropping commercial operations across places such as Fuji, Malaysia, and the Philippines. These plantations tend to be devoid of wildlife because the acidic soil that mahogany thrives on doesn’t support many other organisms. Intensive monocropping also brings various diseases, making these trees vulnerable to weather factors, including the changing climate. 

• Manufacturing mahogany wood is fairly sustainable. This is because mahogany wood dries rapidly, which reduces the energy required for kiln drying. Besides, a significant part of the necessary energy can come from burning wood waste. At least 90% of all thermal energy used for kiln drying in the US hardwood sector is derived from biomass. 
• The transportation of mahogany wood is generally not sustainable. Because mahogany wood in the US would have come a long way—from tropical forests in the Caribbean, Central America, South America, Africa, or Asia—this stage has a relatively high carbon footprint higher than regionally available wood, like black cherry or red oak. 
• The usage of mahogany wood is sustainable.
  • Mahogany can last for a very long time, maintaining its carbon storage role instead of releasing carbon dioxide into the atmosphere. For example, outdoor furniture made from mahogany can last up to 40 years. 
  • Mahogany wood is resistant to rot, mold, and other decay organisms, making it a stand-out option for outdoor furniture. Because mahogany has no pockets or grooves, it is immune to water damage. It is up to 70% more stable than any other form of hardwood like red oak or balsa. 
• The end-of-life of mahogany wood is sustainable. The wood can be upcycled for another project or used to make bioenergy. 

Mahogany is an imported tropical wood with a much higher transporting carbon footprint than hardwoods from US temperate forests. For a long time, mahogany has been exploited for high-end furniture demand in Europe and America, leading to serious reductions in the population of these species. Consequently, mahogany is one of the least sustainable timber materials. If you must choose mahogany wood for your project, opt for reclaimed material or a less vulnerable mahogany wood species with sustainability certifications like FSC or PEFC.

Brazilwood: An Endangered Timber Species Often Wasted in Manufacturing Processes 

Brazilwood is generally considered the best material to make violin bows with and, thus, is quite sought after. Yet the exploitation of brazilwood started much earlier, then as a valuable dye. Its usefulness to humans has led brazilwood trees to having a much smaller population, restricted to several remnants of the Atlantic Coastal Forest. 

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

• Growing and harvesting brazilwood is unsustainable. This is largely due to the diminishing natural habitat of this timber species in the wild and the lack of interest in growing brazilwood trees in plantations.
  • Growing brazilwood trees (Paubrasilia Echinata) in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, because of this timber’s unique properties, the species has repeatedly faced over-harvesting and illegal logging.
  • Overexploitation of brazilwood for dyestuff had reduced the population of brazilwood trees to the extent that it has never fully recovered. The slow growth rates and the continuing demand for brazilwood as an unsurpassed material for violin bows further exacerbate the seriousness of the population reduction. Paubrasilia Echinata is on CITES Appendix II, which is reserved for species that are at risk in the wild and considered to be threatened with extinction. It is also listed on the Red List of Threatened Species by the IUCN as an endangered species. 
  • Harvesting rosewood timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter. For example, these trees provide important habitats for orchids and other epiphytes.
  • Brazilwood trees grown in plantations tend to grow considerably faster than in the wild. Yet, the quality of wood from plantations is not suitable for making violin bows, which is a lucrative trade for this wood, as there is no comparable substitute material. Therefore, there isn’t much interest in growing this species in plantations. 
  • As brazilwood’s principal use today is to manufacture bows for violins and other stringed musical instruments, it is important to take note of the significant wood waste during processing. Between 70%–80% of brazilwood is lost as logs are converted to bow blanks, and a further 70%–80% is wasted while the blanks are turned into bows. 
• Manufacturing brazilwood is fairly sustainable. Drying brazilwood, which could be the most energy-consuming step of manufacturing if using a kiln, can be done naturally. The drying time depends on the thickness of the wood and the weather conditions. However, if opting for kiln-drying, a significant part of the necessary energy can come from burning wood waste. At least 90% of all thermal energy used for kiln drying in the US hardwood sector is derived from biomass. 
• The transportation of brazilwood is generally not sustainable. This stage has a relatively high carbon footprint because brazilwood in the US would have come a long way from Brazil. Brazilwood’s transporting carbon footprint is generally more elevated than regionally available wood, like black walnut or hickory. 
• The usage of brazilwood is sustainable.
  • Brazilwood can last for a very long time, maintaining its carbon storage role instead of releasing carbon dioxide into the atmosphere. 
  • Brazilwood is rated as very durable regarding decay resistance. It is also a very hard wood, with a Janka hardness of 2,820 lbf, which is higher than many other tropical hardwoods, such as rosewood or teak. In further comparison, the white oak, which is considered one of the hardest wood from temperate forests, is 1,350 lbf. 
• The end-of-life of brazilwood is sustainable. The wood can be reused or burned as bioenergy.

Brazilwood is an imported tropical wood, with a higher transporting carbon footprint than hardwoods from US temperate forests. Brazilwood has long been exploited for dyestuff and musical string instruments, leading to serious reductions in the population. Consequently, brazilwood is one of the least sustainable timber materials. If you have to choose brazilwood for your project, opt for certified reclaimed wood.

Lignum Vitae Wood: Exceptionally Strong Wood at the Brink of Distinction 

Lignum vitae wood is also known as ironwood since it is exceptionally hard and heavy, generally considered incomparable by any other traded timber. This wood’s legendary physical properties and supposed medicinal applications are the reasons behind its popularity and, consequently, overexploitation. 

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

• Growing and harvesting lignum vitae wood is unsustainable. This is largely because populations are severely reduced as both the wood and the resin extracts have been overexploited for hundreds of years.
  • Growing lignum vitae trees in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, because of the high demand for lignum vitae wood’s exceptional hardness and weight, these tree species (Guaiacum officinale and Guaiacum sanctum) have faced intense over-harvesting and illegal logging.
  • Overexploitation of lignum vitae wood as medicines and woodworking materials has caused a severe reduction in this species’ population. Population recovery is far behind logging because these trees grow extremely slowly, as little as one inch per year. 
    • Lignum vitae is on CITES Appendix II, which is reserved for species that are at risk in the wild.
    • Lignum vitae is considered an endangered species on the Red List of Threatened Species by the IUCN. 
  • Harvesting lignum vitae timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter.

• Manufacturing lignum vitae wood is not very sustainable. This is because lignum vitae wood dries slowly. Attempts to speed up the drying process can cause serious splitting. However, wood waste can be recycled fully as by-products or biomass pellets to offset the carbon emissions during extended drying processing. 
• The transportation of lignum vitae wood could be sustainable. This stage could have a high carbon footprint if lignum vitae timber is sourced from Central America and the Caribbean. However, these species also grow in Florida, meaning the timber can be transported locally at relatively short distances. 
• The usage of lignum vitae wood is sustainable.
  • Lignum vitae can last for a very long time, even in harsh conditions such as being submerged or in contact with the ground. Consequently, the timber keeps its carbon storage role instead of releasing carbon dioxide into the atmosphere. 
  • Lignum vitae is exceptionally dense and hard. The Janka hardness of lignum vitae is 4,394 lbf, which is three times higher than that of white oak. Based on this indicator, lignum vitae is the second hardest wood from the natural world (only after quebracho). 
  • Furthermore, lignum vitae wood is highly resistant to attack by insects and has an incredible ability to resist any sort of rot.
• The end-of-life of lignum vitae wood is sustainable. The wood can be reused or burned as bioenergy.

Lignum vitae wood comes from endangered hardwood species with an unhealthily low population, which makes it one of the least sustainable timber materials. If you must choose this material for a woodworking project requiring exceptional strength, opt for reclaimed wood from certified sources. 

Meranti Wood: A Critically Endangered Timber Species With a High Transporting Carbon Footprint

The meranti tree species used to dominate their native rainforests, but high demand and lax regulations have led to decades of overexploitation and illegal logging, affecting their native forests’ invaluable biodiversity. 

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

• Growing and harvesting meranti wood is unsustainable. This is largely due to the damage done to the natural habitats of meranti tree species, some of which are incredibly biodiverse.
  • Growing meranti timber trees—Shorea species—in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, illegal logging and over-harvesting for meranti timber have significant ecological costs. 
  • The International Union for Conservation of Nature (IUCN) put 148 species of the 196 Shorea species on its Red List due to the drastic reduction in their population. For example, the population of dark red meranti species has reduced by over 80% in the past three generations. The reasons for such a decline were excessive logging, insufficient natural regeneration, and a slow recovery rate. 
  • Harvesting meranti wood timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter, leading to biodiversity loss. Southeast Asian tropical forests—the epidemic home to most meranti species—are incredibly biodiverse. Reduction in biodiversity there has a very high ecological cost. For example, scientists from the Delft University of Technology calculated that the ecological cost for a window frame made with old-growth meranti from an FSC-certified forest is 22 times higher than when the window is made with wild pine. 
• The sustainability of manufacturing meranti wood varies. 
  • There are five groups of meranti timber, distinguished based on the color of the heartwood: dark red meranti, light red meranti, white meranti, yellow meranti, and balau. 
  • The drying speed varies among different meranti species, from rapid to normal. The drying rate affects the sustainability of manufacturing meranti as kiln-drying is the most energy-intensive part of the production. 
  • Sawing is another energy-intensive step. Electricity and diesel fuel energy needed again vary from species to species (and from sawmill to sawmill). In an environmental performance assessment comparing two sawmills in Malaysia, manufacturing dark red meranti species required more energy and fuel than light red meranti species. 
  • It is important to note that wood waste during manufacturing can be recycled fully as by-products or biomass pellets to offset this stage’s carbon emissions. At least 90% of all thermal energy used for kiln drying in the US hardwood sector is derived from biomass. 
• The transportation of meranti is generally not sustainable. Because meranti wood in the US would have come a long way from Southeast Asian countries, the transporting stage has a relatively high carbon footprint, higher than that of regionally available wood, like hickory or walnut. 
• The usage of meranti wood is not very sustainable. Meranti wood, as a group, is generally not considered highly durable. Balau, for example, is not very resistant to decay and insects. Thus, it doesn’t keep its carbon storage role as long as some other woods, including locally available soft and hardwoods. 
• The end-of-life of meranti wood is sustainable. The wood can be reused or burned as bioenergy.

Meranti wood comes to the US from far-flung Southeast Asian countries, bearing a much higher transporting carbon footprint than local hardwoods. Excessive logging of this group of timber, especially from unmatched biodiverse rainforests, makes meranti wood one of the least sustainable materials for woodworking projects. If you still want meranti wood for your woodworking projects, opt for certified reclaimed meranti wood or FSC-certified meranti timber from less vulnerable Shorea species, which have relatively fast growth rates and are quick to dry. 

Wenge Wood: An Overexploited Hardwood With a High Transporting Carbon Footprint

Wenge wood is beautiful and durable, making it ideal for many projects, from furniture to flooring to musical instruments. However, the high demand for this tropical hardwood from Africa has led to overexploitation of this tree species. 

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

• Growing and harvesting wenge wood is unsustainable. This is largely due to population reduction over several generations of this timber tree species.
  • In their native condition, growing wenge trees—Millettia laurentii species—has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, overexploitation and illegal logging to meet the high demand for wenge wood has serious ecological consequences. 
  • The wenge tree is considered an endangered species on the Red List of Threatened Species by the IUCN, due to a population reduction of over 50% in the past three generations. 
  • Harvesting lignum vitae timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter.
  • Illegal logging of wenge wood is rampant in native forests where wenge tree species grow, from Cameroon to the Democratic Republic of Congo. 
• Manufacturing wenge wood is not very sustainable. Wenge wood dries slowly, and often a kiln is needed. Kiln-drying is the most energy-intensive part of production. It is important to note that wood waste during manufacturing can be recycled fully as by-products or biomass pellets to offset this stage’s carbon emissions. At least 90% of all thermal energy used for kiln drying in the US hardwood sector is derived from biomass. 
• The transportation of wenge wood is not sustainable. Because wenge wood in the US would have come a long way from African countries, the transporting stage has a relatively high carbon footprint, higher than that of regionally available wood, like white oak or black cherry. 
• The usage of wenge wood is sustainable.
  • Wenge wood can last for a very long time, maintaining its carbon storage role instead of releasing carbon dioxide into the atmosphere. 
  • Wenge wood is extremely durable, thanks to its natural oils and structure. It is also naturally resistant to abrasion, rot, and termite attack. Furniture and flooring made of wenge wood can last for decades when dried and cared for properly.
• The end-of-life of wenge wood is sustainable. The wood can be upcycled for another project or burned as bioenergy.

Wenge wood is an imported tropical wood with a much higher transporting carbon footprint than hardwoods from US temperate forests. Its dwindling population makes it one of the least sustainable timber materials. If you must choose this material for a woodworking project requiring exceptional durability, opt for reclaimed wood from certified sources.

Merbau Wood: A Highly Durable Hardwood That Has Been Long-Exploited 

Merbau wood is favored in homes because of its aesthetic color and durability. However, high demand for this valuable hardwood drives unsustainable harvesting practices and illegal logging in tropical forests, causing great biodiversity loss. 

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

• Growing and harvesting merbau wood is unsustainable. This is largely due to the population reduction over several generations of this group of timber trees.
  • Growing merbau trees—Intsia species—in their native conditions, spreading from East Africa to Southeast Asia and Australia, has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, overexploitation and illegal logging to meet the high demand for merbau wood has many ecological consequences. 
  • The merbau tree is considered a vulnerable species on the Red List of Threatened Species by the IUCN due to a population reduction of over 20% in the past three generations. Because these trees grow slowly, it is challenging for population recovery to catch up with logging. 
  • Merbau trees grow sparsely even in rich forests. This means two things: Firstly, the population of old-growth merbau trees is relatively small. Secondly, loggers often end up cutting down many other trees to reach a targeted merbau tree.
  • Harvesting sapele timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter. For example, Intsia bijuga (a species of merbau) trees make up a core foundation of the mangrove swamps. This unique and highly beneficial ecosystem is important to Northern Australia and Southeast Asia. Wildlife such as shrimp, crabs, and mud lobsters who make their home in those swamps are losing their habitat to timber harvesting. Mangrove swamps protect us from storm surges and tsunamis thanks to their ability to absorb wave energy, and to lose them is to lose our defense against natural disasters. 
  • Illegal logging and fraudulent trading of the species are widespread and treacherous, driven by poor governance in growing countries and high demand from importing countries like China. Greenpeace estimated that up to 80 percent of logging in Indonesia, the main origin for merbau timber, is illegal.

• Manufacturing merbau wood is not very sustainable. Merbau wood dries slowly, and often a kiln is needed. Kiln-drying is the most energy-intensive part of production. It is important to note that wood waste during manufacturing can be recycled fully as by-products or biomass pellets to offset this stage’s carbon emissions. At least 90% of all thermal energy used for kiln drying in the US hardwood sector is derived from biomass. 
• The transportation of merbau wood is not sustainable. Because merbau wood in the US would have come a long way from these species’ last stands in Southeast Asia, the transporting stage has a relatively high carbon footprint, higher than that of regionally available wood, like black cherry or cedar. 

• The usage of merbau wood is sustainable. 
  • Merbau wood can last for a very long time, maintaining its carbon storage role instead of releasing carbon dioxide into the atmosphere. 
  • Merbau is highly durable, thanks to its density and strength. The wood contains natural oil with a high tannin content, contributing to its resistance to weathering, decay, and termites. In terms of lifespan, even outdoor merbau products can last for decades, somewhere between 15 to 40 years. 
• The end-of-life of merbau wood is sustainable. The wood can be upcycled for another project or burned as bioenergy.

Merbau is an imported tropical wood with a much higher transporting carbon footprint than hardwoods from US temperate forests. Because of its slow growth and sparse distribution, illegal logging and overharvesting have huge ecological consequences, making it one of the least sustainable timber materials. If you want this material for your home, only use reclaimed wood from certified sources.

Sapele Wood: An Overly-Harvested Hardwood With a High Transporting Carbon Footprint

Sapele wood is a durable African hardwood, which is a highly-prized alternative to genuine mahogany. The high demand for this tropical hardwood as a long-lasting material for furniture, luxury flooring, and musical instruments has led to the rapid decline of this species’ population. 

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

• Growing and harvesting sapele wood is unsustainable. This is largely due to a population reduction over several generations of this timber tree species.
  • Growing sapele trees—Entandrophragma cylindricum species—in their native conditions has the environmental benefits of carbon sequestration and storage in the root system and the tree trunk. However, overexploitation and illegal logging to meet the high demand for sapele wood has many ecological consequences. 
  • Sapele tree is considered as a vulnerable species on the Red List of Threatened Species by the IUCN, due to a population reduction of over 20% in the past three generations. Because these trees grow slowly, it is challenging for population recovery to catch up with logging. 
  • Harvesting sapele timber unsustainably—illegally and/or in excess numbers—disrupts wild animals, which depend on the forest for food and shelter. For example, sapele trees provide habitat for rare monkey species, such as Thollon’s red colobus and mandrills. The African rainforests—sapele trees’ native habitat—are unique. Interestingly, these forests store more carbon than those in the Amazon rainforests. On average, a hectare of African rainforest stores 1.3 times more carbon than the same area of the Amazonian rainforest.

• Manufacturing sapele wood can be sustainable. This is because sapele wood dries rapidly, which reduces the energy required for kiln drying. Besides, a significant part of the necessary energy can come from burning wood waste. At least 90% of all thermal energy used for kiln drying in the US hardwood sector is derived from biomass. 
• The transportation of sapele wood is not sustainable. Because sapele wood in the US would have come a long way from African countries, the transporting stage has a relatively high carbon footprint, higher than that of regionally available wood, like white oak or pine. 
• The usage of sapele wood is sustainable.
  • Sapele wood can last for a very long time, maintaining its carbon storage role instead of releasing carbon dioxide into the atmosphere. 
  • Sapele is a strong hardwood with a high Janka hardness (1,510 lbs). It is harder than most domestic North American species and almost twice as hard as genuine mahogany. Regarding density, sapele timber is comparable to red oak. 
  • Besides, sapele wood is decay-resistant and somewhat insect resistant. 
• The end-of-life of sapele wood is sustainable. The wood can be upcycled for another project or burned as bioenergy.

Sapele wood is an imported tropical wood with a much higher transporting carbon footprint than hardwoods from US temperate forests. Its rapidly-decreasing population makes it one of the least sustainable timber materials. If you must choose this material for a woodworking project, opt for reclaimed wood from certified sources.

How Can You Buy More Sustainable Wood

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

• Forest Stewardship Council: 

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

• Program for Endorsement of Forest Certification: 

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 can 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 biodiverse forests in tropical climates is more significant (and sometimes less properly recorded) than in temperate, well-managed logging forests. 

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.

Final Thoughts

The ten least sustainable types of wood are as follows: 

1. Ramin 
2. Rosewood
3. Ebony
4. Mahogany
5. Brazilwood
6. Lignum Vitae
7. Meranti
8. Wenge
9. Merbau
10. Sapele 

These woods are unsustainable because their populations have been repeatedly reduced, being subject to over-harvesting and illegal logging. They also come from tropical forests with unmatched biodiversity and high carbon storage capacity. 

However, if you must choose these types of wood, follow these steps to make your use more sustainable:

• buy reclaimed wood
• keep the wooden products for as long as possible, and
• at the end-of-life of a wooden product, upcycle the wood to extend its usage and arrange for it to be recycled or properly disposed of.

Stay impactful,

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