3 Disadvantages Of Eucalyptus Wood You Must Know Of!

The mighty eucalyptus tree has been harvested and cultivated for its wood for hundreds of years. The first trees were brought into the US during the 1950s, during a timber shortage in the country. It continues to be used in everything from construction and furniture to posts and poles.

Sadly, it is not without its disadvantages.

There are a few significant drawbacks to eucalyptus wood. It has a lot of moisture as a tree, which escapes rapidly when drying, causing distortion and cracking. The wood is also prone to expand and contract quite aggressively and is vulnerable to certain pests and elements.

Eucalyptus furniture can be pretty and, depending on the variant of Eucalyptus used, very durable. But if you are considering building or carving something with Eucalyptus wood, you need to know that you are in for a potentially challenging ride.

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Not All Eucalyptus Is Equal

The first point that must be made clear is that Eucalyptus refers to a family of trees containing more than 700 subvariant species. Not all these species share the same blanket strengths and weaknesses.

Native to Australia, the Eucalyptus Grandi is a heavy, strong, and durable wood. Many of the positive qualities associated with Eucalyptus are thanks to the Grandi brother in the family.

3 Disadvantages of Eucalyptus Wood You Must Know Of!

However, if you want a proper Grandi in the US, you will need to import it as a Grandi tree in Australia doesn’t grow the same as a Grandi tree in the US.

My dad has recently retired from a long career as a Forester in South Africa.

The primary trees cultivated in South Africa (SA) are Pine variants. Pine in SA is cheap, soft, and not ideal for anything other than construction.

These qualities are not the case, however, for Oregon Pine.

The Oregon Pine that can still be found in SA was imported one hundred or so years ago due to a shortage of wood in the country. The wood is highly sought after and expensive, yet our own pine trees are not.

That is because a tree reared in its native homeland grows very different from where it grows as an unchallenged alien.

When Eucalyptus was imported into the US, it had no natural enemies, and it thrived, growing and spreading fast. Too fast.

A tree that grows too fast is softer and contains more moisture than slower-growing native species.

Because of this same distinction, the US Blue-Gum Eucalyptus is generally disliked, especially when compared with something like Grandi. So, if you are committed to using Eucalyptus, I would strongly urge you to make sure you get the correct variant.

If you get the wrong one, the rest of this article may become very personal to you.

The Downsides Of Eucalyptus

Although we did have a lot of eucalyptus plantations where I grew up, I was pretty surprised when I first heard of it being used for furniture. We cultivated it as strong poles and fence posts for its benefits, and the larger timber was milled up and turned into pallets.

Its bad reputation isn’t unfounded either, as the wood has a few drawbacks that some consider dealbreakers. Here I will discuss three common problems during the three phases of processing: Milling the log, building furniture, and maintaining and looking after it.

The Milling Problem:

Eucalyptus Is Prone To Cracking

Eucalyptus trees are infamously thirsty, drinking between 20 and 50 gallons of water every day. When the tree is felled and no longer drinking up all that fluid, it enters the drying process. Eucalyptus wood dries quickly, and as it dries, it expels all that water, which took up quite a bit of space in the wood.

This process makes the wood extremely prone to cracking as the wood fibers and grains pull away from each other. Walking around my local neighborhood, I think I would be hard-pressed to find even a single eucalyptus pole without a crack or two running down its length.

Cracking is increased if it is milled using a plain saw, which cuts through the entire width of the log, creating long wide slabs. To avoid this, Eucalyptus is often milled using a radial saw which divides a log into quarters down its length and then cuts thinner planks from those quarters.

Below is a video example of plain milling eucalyptus, which results in bursts and cracks only a few days after the milling process has been completed:

Preventing cracking is a tricky business. Air drying before milling is probably the best option you have, especially if you can slow down the drying process as much as possible (easier said than done). Alternatively, you can season the log, leaving it to dry longer.

Once you are ready to mill, you can try radial milling (if you have the tools for it). If you can only plain mill, then the general community advice is to keep the slabs short and narrow. Don’t expect to mill an entire tabletop from a single blue-gum slab; it’s just going to end badly for you.

The Building Problem:

Eucalyptus Changes Shape

Contortion has its place. It’s a fantastic art and entertaining to watch during a performance of Cirque Du Soleil.

However, it’s not so much fun to see a newly joined tabletop contort itself into a twisty. Unfortunately, this is one of the risks of Eucalyptus.

The large corporation my dad worked for had the biggest sawmill in the district, by far.

It was not the only sawmill, but the biggest. The corporation cultivated a lot of Eucalyptus, but they could never figure out the secret to making good pallets with it.

Every time they tried, their fresh batch of newly assembled pallets would warp and bend and effectively become useless.

However, one of the smaller mills figured it out and, in a gallant effort to protect the “little-man,” we all kept their secret. See, this small company also made bricks, and what they did was raise their wet bricks of the ground and dry them on, yup, you guessed it, their newly built, wet pallets.

Once the bricks had cured, the pallets were dry and straight, ready to be sold.

Eucalyptus is prone to swelling and shrinking with the humidity and contact moisture. So, if you are planning a project involving Eucalyptus, it is a good idea to build it in sections and weigh those sections down for a week or so.

Doing so may mean taking longer to complete your project, but it could also mean your project staying in its intended shape.

The Final Problem: Eucalyptus Furniture Needs TLC

Your slab has made it through the mill, and you’ve built that table slowly and carefully.

Now you need to make it last.

Every piece of wood furniture will require some level of TLC, but there are a few threats to Eucalyptus specifically.

1. Eucalyptus Vs. The Cold

Eucalyptus’ place of honor is mainly in the sphere of outdoor furniture. Because it is technically a hardwood, it can last a long time. It’s often used as a cheaper competitor of teak.

Its biggest foe, however, is the cold. Although once built and treated, it’ll handle snow and contact moistures reasonably well (thanks to the high oil level of the wood), it does not like cold temperatures.

All woods contract to varying degrees in low temperatures, but Eucalyptus’s contortion takes it to a whole new level of committed deformation. You may very well see your favorite patio table just bursting with joy at the arrival of winter. Your happiness, on the other hand, will be pretty frozen.

If you live in a cold winter environment like the Pacific Northwest, I strongly suggest moving your furniture indoors for the winter. If it is indoor furniture, regular and proper treatment will go a long way to helping solve this problem, and some of the others to follow.

If you live somewhere with hot Summers and freezing Winters, then perhaps opt for a different wood type. I don’t suggest going for Eucalyptus in extreme climates.

2. Eucalyptus Vs. Pests

When Eucalyptus was first introduced, it had very few natural pest enemies. But, being an alien species in the USA, it naturally got a bit out of control, and later, pests were introduced to stunt its rate of unwanted spread.

According to studies, one such pest, the Eucalyptus Longhorned Borer, was introduced in the late 80s and later, accidentally released into large cultivators worldwide.

Alongside the borer, several other pests have a biologically programmed fondness for Eucalyptus, both in a standing tree or completed-furniture form.

Longhorned borers usually bore out wood close to the surface, so identifying them by their trademark holes is not difficult. Dry eucalyptus wood is particularly attractive to them.

Protecting your country-side furniture from them starts outside, moving in.

If you have stockpiles of eucalyptus firewood or other eucalyptus timber around your yard, make sure you treat them regularly with effective insecticides, for example.

Those stockpiles are the ideal breeding ground for borers.

Your furniture should also be treated and sanitized regularly. I suggest removing any piece of wood or furniture at the first sign of borers or consulting an expert to assist with eradication before they spread to other furniture pieces.

3. Eucalyptus Vs. The Sun

This consideration is again valid of all wood types to varying extents but particularly important in the case of Eucalyptus. While effective against specific other threats, the natural oils do nothing to protect the wood from the UV rays of the sun.

There is probably a reason why I have never heard of Eucalyptus being used for window frames or exterior doors (I’m not saying they don’t exist, just that they are uncommon). Eucalyptus tends to degrade and decolor rather quickly with prolonged exposure to direct sunlight.

You may see evidence of sudden color degradation or even complete color changes if you do not treat your furniture regularly. Even when used for poles, Eucalyptus needs to undergo extensive treatment before being planted to help combat UV decay.

In addition to regular treatment, you could also keep your indoor eucalyptus furniture away from direct and prolonged sunlight. For outdoor furniture, consider covering it with a tarp when it is not being used, or consider placing them on a shaded patio or under a shaded gazebo.

4. Eucalyptus Vs. People

Although reasonably uncommon, there have been reports of people experiencing allergic reactions to Eucalyptus. The oils in the wood are pretty strong and have a lot of medicinal value.

In South Africa, the oils are used for one of the most common (and, should I say, “magical”) ointments, known as Zambuck. But, as with most oils, ointments, and medicines, some people are simply allergic to them.

As mentioned extensively in this article, Eucalyptus also requires a lot of treatment and possibly pesticides and insecticides. These treatments and pesticide chemicals are often more directly related to potential allergic reactions than the wood itself.

So, the very thing keeping your wood healthy could end up making you sick.

Irony is a beautiful thing.

Why Would Anyone Buy Eucalyptus Then?

With all these significant problems listed, it can be difficult to understand why people would even consider purchasing Eucalyptus at all. Still, it’s not all bad, and there are some profound benefits to the wood.

Firstly, although Eucalyptus has a few elements that threaten its longevity, you will still get a long life out of the wood by giving it regular treatment.

Even though it struggles against the sun and pests, it does surprisingly well against typical rot and decay, a likely additional benefit of its high oil content and the nature of the oils themselves. Caring for your Eucalyptus can see you getting a good 20 to 25 years of outdoor use out of it.

Secondly, Eucalyptus can be beautiful. The right type of Eucalyptus may deepen its color to a reddish tint as it ages. The wood also has a significant variation of grain patterns. Some sections have very light, matted grain and others have dark, pronounced patterns.

I personally love this feature of Eucalyptus because it really adds character and uniqueness. As the piece ages, it not only gains that red tint, but the grain becomes darker and more exaggerated.

Indoor pieces, which naturally last longer, will benefit from this color change over time.

Finally, Eucalyptus can be cheaper than the competition while having a lot of the same benefits and features. Just don’t be swindled by exotic promises and terminology. Do your homework before you buy, and you can find yourself saving a pretty penny.

There was an area of very old eucalyptus trees in a remote area of the plantation felled a few years back. The wood was exported from South Africa to Vietnam, turned into patio furniture, and sold in Australia (the home of Eucalyptus) as “Vietnamese Gum Furniture.” I repeat, be careful of exotic labels and promises.

Conclusion

Eucalyptus can be a beautiful and cost-effective alternative wood that may still last you almost just as long as rarer, more expensive woods, provided that you look after it. If you are considering milling, building with, or purchasing eucalyptus woods, be aware of some of the potential downfalls.

The wood is prone to cracking, extensive shrinking and contorting, and is still vulnerable to certain pests, climates, and conditions. Once you get your table built, crack-free, however, regular treatment and care should mitigate many potential threats it faces.

References

http://ipm.ucanr.edu/PMG/PESTNOTES/pn7425.html