Ash trees can take hold of almost everywhere as they agree with a great variety of soil and situation – greater than any other tree producing timber of equal value. Once widespread across the Eastern United States, the population of ash trees has declined significantly due to the Emerald Ash Borer (EAB) infestation. So we had to ask: How sustainable is it to buy products made out of ash wood?

Ash wood is sustainable because ash trees capture carbon from the atmosphere, and ash furniture stores it for decades. As many ash trees have died from EAB, reclaiming timber from dead trees is much more sustainable than harvesting live trees.

In this article, we’ll walk you through the life-cycle of ash wood used for furniture, flooring, or other products. Then, we evaluate its sustainability, potentials, and shortfalls. And in the end, we’ll show you tips for buying sustainable ash wood. 

Here’s How Sustainable Ash Wood Is

Ash wood is one of the most durable American hardwoods and has long been used to make furniture and flooring. The high adaptation and the carbon storage potential make ash wood a sustainable material if and when the EAB infestation is kept under control.

“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

To understand the sustainability of ash wood, we assess the life-cycle of furniture and flooring. This life-cycle assessment (LCA) is a method to evaluate the environmental impacts of each stage in a product’s life-cycle, from the making to the recycling. Over the years, companies have strategically used LCA to research and create more sustainable products. 

In this article, we’ll use the cradle-to-grave perspective of the LCA, examining the five stages of the life-cycle of furniture made with ash wood.

Overall, we can say that ash wood is sustainable. However, the rapidly diminishing number of ash trees caused by the Emerald Ash Borer (EAB) insects means reclaimed ash wood is currently the most sustainable option for furniture. Let’s dive deeper into each stage of ash furniture’s life-cycle and find out how it can be more sustainable. 

How Sustainable Is the Growing Ash Wood

Growing ash trees is sustainable thanks to the potential for carbon sequestration (i.e., capturing and storing carbon) and their adaptation to many soil types. However, EAB beetles have been killing too many ash trees in the U.S. forests making harvesting wood from live ash trees unsustainable. 

What Type of Wood is Ash and What Does This Mean for Sustainability

Ash is a hardwood tree in the olive tree family. North American forests host a dozen of ash species. Their growth rates range from medium to fast, ranging from 13 inches per year (white ash) to more than 24 inches per year (green ash).

How Sustainable Does Ash Wood Grow

Growing ash is sustainable because of its potential for carbon sequestration and high adaptation to many soil types and climates. 

• Carbon sequestration: The carbon sequestration potential of ash trees is significant. As they grow, they absorb CO₂ from the atmosphere while releasing oxygen. During their long lifespan – 300 years for some ash species – they act as a carbon sink. This means that they are taking greenhouse gases out of the atmosphere, helping to mitigate the climate crisis. And they can store a lot, growing tall, as tall as 120 feet (white ash), and big with a 2-to-3-diameter trunk. 
• Diverse land use: Ash grows well and regenerates naturally throughout the eastern United States in mixed hardwood forests. The ash trees adapt and thrive within a wide range of latitude, climate, and soil conditions without any need for fertilizer or irrigation. 

The sustainability of ash timber largely depends on the situation of the Emerald Ash Borer infestation. The pest was introduced to U.S. forests from Asia in the 1900s. Since then, it has devastated local populations of ash trees, which used to be highly abundant. According to the Emerald Ash Borer Information Network, the pest killed more than 99% of ash trees in some forests.

EMA larvae bore into a tree and feed on the inner bark, eventually killing the entire tree. Many infected trees die within a few years. Harvesting the wood of those dead trees to make furniture, such as in this project, is more sustainable – a much better option than cutting live ash trees when their population is under such a serious attack. 

Where Is Ash Wood Usually Grown

Ash trees grow across the North American continent as well as Europe, Asia, and Africa. In the U.S, the distribution of ash species spreads the whole of the eastern side, from New York to the Gulf of Mexico.

There are 60 species of ash trees around the world. Some common North American native ash species are white ash, black ash, green ash, blue ash, and California ash. Green ash and black ash trees are the most vulnerable to EAB, followed by white ash and blue ash. 

Ash trees hardly ever grow in pure stands but with other hardwood trees in the South and in conifer forests of the North. The trees provide a home and food for numerous birds, insects, and squirrels. While ash trees can regrow from stumps after their trunk being cut for timber, the loss of branches and leaves means wild animals lose their habitats at least until the trees grow back.

As ash wood becomes less available due to a reduction in tree population and EAB-related restrictions that prevent transporting ash timber across states, you might consider buying imported ash furniture. However, you might want to double-check its certifications as illegal logging for ash is a major problem in Europe. And buying illegally logged ash woold would not be a sustainable option.

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. 

How Sustainable Is the Manufacturing of Ash Wood

Turning ash wood into furniture has a relatively low carbon footprint because wood waste can be recycled fully as by-products or biomass pellets to offset the carbon emissions during harvesting and processing. 

The first step of manufacturing ash furniture involves cutting down trees and turning them into lumber in a sawmill. The carbon emissions here come from electricity usage. 

The next step is to dry lumber and then turn it into furniture. Ash dries fairly fast, dries fairly fast, about three times faster than slow drying woods like oak or hickory. It means a low energy consumption for kiln drying. Besides, a high proportion of energy can come from burning wood waste. At least 90% of all thermal energy used for kiln drying in the U.S. hardwood sector is derived from biomass.

How Sustainable Is the Transportation of Ash Wood

Transporting ash wood is a relatively carbon-intensive stage in the life-cycle of ash furniture due to the emissions associated with operating the hauling vehicles that take timber to sawmills and factories, then furniture to stores.   

As ash trees are distributed widely in the U.S, a piece of ash furniture would have a lower carbon footprint than that made from imported woods like mahogany, providing they are both sold in the U.S.

The actual emission during this stage depends on the type of vehicles used, the fuel they need, and the distance the wood travels. Calculations made by the Norwegian Forest and Landscape Institute showed that smaller wood hauling trucks emitted more CO₂ per transported cubic meters of timber: 1.25 times more than larger wood hauling trucks, 1.3 times more than sea vessels, and six times more than freight trains. Therefore, the sustainable transportation option would be rail or large trucks running on biofuel. You can check with your wood suppliers how their products are transported and opt for the more sustainable choice. 

How Sustainable Is the Usage of Ash Wood

Using ash furniture can be sustainable thanks to the carbon capture during the products’ long life. 

Ash is one of the most durable hardwood species in the U.S. The wood is heavy, hard, and resistant to scratch and damage. Indoor ash furniture can last for several decades with little care.  

When wood is decayed, either naturally in the forest or because of damage caused by usage at home, the carbon stored in the wood is released back to the atmosphere. Therefore, long-lasting furniture can be considered a good way of keeping carbon out of the atmosphere. If the wood is then reclaimed for making another piece of furniture, its positive carbon storage environmental impact is even higher. 

How Sustainable Is the End-of-Life of Ash Wood

The end-of-life stage for ash furniture is sustainable when the wood is reused or burned as bioenergy. 

There are a few scenarios for wood products – furniture, flooring, and household items – at the end of their life. 

They can end up in landfills and don’t decompose. In this case, it keeps its role as carbon storage. 

Wood products can also be upcycled and reused, extending their role as carbon storage and reducing the fossil CO₂ emitted as much as four times when comparing, for example, a recovered hardwood flooring with a new one. New wood products often travel much further to their markets, compared with recovered wood products. The latter is typically made in urban centers and sold locally, which lowers the transportation environmental burdens. 

In another end-of-life scenario, products like an ash wood table can be burned for biomass energy displacing coal or natural gas in generating electricity. 

With smaller household items, like a doorknob or a small chair, the offset won’t be as high as there is much less waste for burning. However, if such products are made from manufacturing wood waste as by-products, their carbon footprint is minimal. 

How Can You Buy Ash Wood More Sustainably

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. 

Because of the devastating impact of EAB on mature and young ash trees, the most sustainable option is to buy furniture made with ash timber reclaimed from dead trees. 

Why Is It Important to Buy More Sustainable Wood

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

You can buy sustainable furniture made from ash wood as long as the material comes from sustainably managed forests. The best option is ash timber reclaimed from trees killed by EAB. And, to make it even more sustainable, use any ash furniture for as long as you can, upcycle the material to extend its usage, and arrange for it to be recycled fully.

Stay impactful,

Sources

• USDA: Emerald Ash Borer Beetle
• Science Direct: Life-cycle assessment (LCA)
• MIT SMR: Strategic Sustainability Uses of Life-Cycle Analysis
• Science Direct: Cradle-to-Gate Assessment
• Emerald Ash Borer Information Network: Homepage
• Aborday: White Ash Tree
• Aborday: Green Ash Tree
• Garden Guides: The Lifespan of Ash Trees
• NC STATE EXTENSION: Fraxinus americana
• AMERICAN HARDWOOD EXPORT COUNCIL: AMERICAN ASH
• THE WOOD DATABASE: WHITE ASH
• YSNews: Let furniture rise from the ashes
• Gardening Know How: Ash Tree Identification
• Springer Link: Analysis of DNA profiles of ash (Fraxinus excelsior L.) to provide evidence of illegal logging
• Our World in Data: Deforestation and Forest Loss
• Impactful Ninja: How Sustainable Is White Oak Wood? Here Are the Facts
• American Hardwood: Environmental Life-Cycle Assessment
• Impactful Ninja: How Sustainable Is Mahogany Wood? Here Are the Facts
• Science Norway: Larger logging trucks give less CO₂ emissions
• Timber Blogger: Ash Wood Properties | Its Advantages and Disadvantages
• Research Gate: Life-cycle primary energy and carbon analysis of recovering softwood 
• Forest Stewardship Council
• Program for Endorsement of Forest Certification
• Our World in Data: Epidemic Mammal Species