World’s Strongest Woods

by Eric Meier

How do you define wood strength?

The simplest and most common way people define if a wood is “strong” is usually hardness. I’ve written about wood hardness before—as a matter of fact, I even have an entire poster ranking the hardness of all sorts of woods worldwide. But this is a very one-dimensional way of approaching the question.

A pair of wooden dumbbells made of various dense hardwoods.

Here are some questions to consider:

  • What if we want to make a ramp where heavy machinery will be wheeled across the wood? We don’t want the planks to break. 
  • How about a bookshelf, where a continuous load will be applied? We don’t want the wood to bow or sag.
  • What if we are making chair legs which will need to support a lot of weight parallel to the grain? We don’t want the wood to be crushed and give out.

All of the above scenarios have nothing to do with wood hardness. They are real-world examples that parallel totally separate wood tests (modulus of rupture, modulus of elasticity, and crushing strength, respectively).

Strength and density: imperfectly correlated

When it comes to the relationship between wood hardness and density, the two statistics are very closely correlated—so much so that the USDA has a publication on estimating wood hardness based on a wood’s specific gravity. However, the same level of correlation cannot be claimed for most other strength properties.

Here’s an example of two woods to illustrate this point:


Lignum Vitae

Guaiacum spp.

Average dried weight: 79 lbs/ft3 (1,260 kg/m3)

Janka hardness: 4,390 lbf (19,510 N)

Modulus of elasticity: 2,481,000 lbf/in2 (17.11 GPa)


Wenge

Millettia laurentii

Average dried weight: 54 lbs/ft3 (870 kg/m3)

Janka hardness: 1,930 lbf (8,600 N)

Modulus of elasticity: 2,550,000 lbf/in2 (17.59 GPa)

When comparing the two wood species above, it should be apparent that there’s somewhat of a contradiction in the data. Lignum vitae is one of the heaviest, hardest woods in the world. By comparison, while wenge is still a rather hard and heavy wood, it’s considerably lighter and softer than the lignum vitae—yet its modulus of elasticity (on average) is higher than that of lignum vitae. So what’s the explanation?

Wood strength is complicated

Think of wood as a very intricately patterned structure, composed of different components in varying lengths, thicknesses, and intertwining patterns. It’s difficult to speak in generalities with a high degree of certainty, but here are some things to consider in a wood’s grain and its influence on strength.

  • An increased microfibril angle (MFA) in the wood’s cell walls may lead to a decrease in modulus of elasticity.
  • Heartwood extractives may deposit substances into the wood that can reinforce and strengthen the wood fibers.
  • Conversely, heartwood extractives may deposit substances that otherwise bloat wood density without positively impacting strength. 
  • Large groups of rays, parenchyma cells, or very large earlywood pore rows may create localized weak points in the wood on a small scale that are negated in larger pieces of timber.
  • Knots and other defects are sometimes unavoidable in some species, and will effect different strength properties to varying degrees (e.g., a knot may increase a wood’s hardness in that area, but decrease its overall bending strength).

Coming up with a good definition of “strong”

It should be apparent that wood strength is so much more than simply wood hardness. But there are a nearly endless number of ways to test and measure different properties of woods. You can test for stiffness, hardness, rupture resistance, impact resistance, shear resistance, crush resistance, wear resistance, and tensile strength. Also, most of these properties will have different strengths on different axes—whether parallel or perpendicular to the grain, etc. 

So what’s the best definition of strong? In an ideal world, every single wood species would have meticulous data published on every possible facet of its mechanical properties, but that’s just not practical. There are all sorts of gaps and missing data, and we have no way of reliably predicting what these values will be—this is especially true of the more obscure tests. The best definition lies somewhere between using everything (impractical) and just hardness (too simplistic).

The sweet spot: the big three

Amidst the sea of all the wood strength tests performed worldwide over the decades, there are three tests that consistently show up in nearly every evaluation. (Not surprisingly, they are also the three strength tests that I’ve chosen to include throughout the Wood Database.) The big three, listed in what I believe is their order of importance, are:

So these three terms, along with Janka hardness, will form the four ingredients that we will use to come up with an overall picture of a wood’s strength level. We need to create a multi-faceted profile to come up with a well-rounded representation of what is “strong.”

The problem is that each of these tests use completely different units of measurements, scales of magnitude, and are generally not directly comparable. Each of these facets will need to be standardized on a scale that preserves their significance, but strips them of their units of measurement.

So, let’s find the world’s strongest wood

What I’ve done is taken each of the four tests of wood strength (Janka hardness, MOE, MOR, and crushing strength) and found which species were the best and worst in that category, and then use those values as the upper and lower limits. (This is limited to the data I have on hand at the present, and could be revised or updated at a later time.) All the values in each category were then subtracted by the amount of the lower limit to serve as a baseline zero.

Next, each of the values were divided by the upper limit for each category, and then that value is multiplied by 100 to serve as a percentage, and voila! We have a straightforward ranking from 0-100 in each of the four categories. This ranking would represent, as a percentage, how strong a given wood is in comparison to the species with the top mark for that category.

Averaging across the four categories gives us an overall “strength index” from 0-100. A perfect score of 100 would be theoretically impossible unless a single wood species was the leader in all of the four tests (hint: none of them led in even two categories).

Let’s first review the leaders in each category:

Janka hardness

Waddywood (Acacia peuce)

Common Name: Waddywood

Scientific Name: Acacia peuce

Best-in-class Janka hardness: 4,630 lbf (20,600 N)

Notes: Despite its colossal hardness value (as well as its extreme density), waddywood has absolutely no available strength test data available. And so unfortunately, it has to be disqualified from the strength rankings due to lack of data. There simply isn’t a strong enough correlation between density and various strength properties to make an accurate estimate that would do justice to this unique wood (as the comparison between lignum vitae and wenge listed above illustrates). 

Modulus of elasticity

Coracao de negro (Swartzia panacoco)

Common Name: Coracao de negro

Scientific Name: Swartzia panacoco

Best-in-class MOE: 4,517,000 lbf/in2 (31.15 GPa)

Notes: This South American native is a very close relative to the better-known exotic katalox—but with a slight bump-up in nearly every category. A serious contender for the title of world’s strongest wood—which is a pattern to note across the entire Swartzia genus and the slightly broader Swartzieae tribe. The only caveat is that I could not find any published data on hardness for this particular species, so an estimated value (presumably slightly under-estimated, especially when compared with other Swartzia species) had to be used. 

Modulus of rupture

Common Name: Pintobortri

Scientific Name: Pouteria eugenifolia

Best-in-class MOR: 37,560 lbf/in2 (259.0 MPa)

Notes: An extremely obscure species, the associated wood picture here is technically from a related species in the same genus, P. sapota. At the moment, the only confirmed images of this wood I could find online were a pair of black and white photos taken from the Samuel J Record wood collection—a collection of samples that was acquired by the USDA’s Forest Products Laboratory back in 1969, and whose specimens probably date to decades earlier. A few caveats: first, the data comes from only a single source; secondly, the hardness is estimated from density. (In this case, with its extremely high reported specific gravity, the estimated hardness may be over-estimated—theoretically it exceeds even the class-leading waddywood listed above.) Any record-holding will be with an asterisk.

Crushing strength

Common Name: Suriname ironwood

Scientific Name: Bocoa prouacensis

Best-in-class Crushing Strength: 19,000 lbf/in2 131.1 MPa)

Notes: Another South American native, this species is a close relative to katalox, with both species being included in the tribe Swartzieae (though in separate genera). But along with the other top contenders listed above, Suriname ironwood comes with the caveat that there is no known hardness value published, so an estimated value was used based on specific gravity. So along with the other leaders, this puts any would-be record-holding in asterisk territory.

Bottom of the heap

Common Name: Quipo

Scientific Name: Cavanillesia platanifolia

Notes: While each of the four titles for strength categories were awarded to different wood species, when it came to the lowest values, it was a sweep across the board—earning quipo a perfect strength index score of 0. Quipo wood was the subject of a 1955 USDA study that evaluated its suitability as a replacement for balsa, and while it was found that the wood had a similar light weight, it was also equal or slightly weaker in nearly all metrics. (Note, the wood pictured is actually that of Tilia cordata, a species of basswood or linden that’s in the botanically-related Malvaceae family.)

And with all of the groundwork, rationale, and explanations out of the way, let’s finally take a look at the all the data and see where all of the woods rank!

Wood power rankings chart

*estimated values

Strength
index

Common Name

Scientific Name

Janka
index

MOE
index

MOR
index

Crush
index

95.3PintobortriPouteria eugenifolia102.397.6100.081.5
91.3Suriname ironwood Bocoa prouacensis93.984.986.3100.0
83.3Coracao de negroSwartzia panacoco73.2100.076.983.1
80.3KaneelhartLicaria canella62.285.981.891.1
79.8SnakewoodBrosimum guianense81.973.074.190.3
78.1KataloxSwartzia cubensis78.781.373.479.1
77.5WamaraSwartzia benthamiana78.977.074.779.3
75.5Endra endraHumbertia madagascariensis94.164.568.275.2
75.1CongotaliLetestua durissima69.475.085.670.4
70.7GidgeeAcacia cambagei92.155.459.675.9
70.4IpeHandroanthus serratifolius75.669.266.870.0
69.8BulletwoodManilkara bidentata67.372.673.066.4
69.8CumaruDipteryx odorata71.570.166.171.5
68.9SaffronheartHalfordia scleroxyla62.765.675.371.8
68.8GreenheartChlorocardium rodiei54.277.974.069.2
68.5EkkiLophira alata69.358.874.471.7
68.2CurupayAnadenanthera colubrina78.256.969.967.8
67.3African BlackwoodDalbergia melanoxylon79.055.281.653.3
66.7BloodwoodBrosimum rubescens62.264.865.874.0
66.6Grey IronbarkEucalyptus paniculata64.568.366.966.7
65.9QuebrachoSchinopsis quebracho98.750.752.661.6
65.7Iron birchBetula schmidtii51.255.089.666.9
65.3Red MangroveRhizophora mangle59.277.162.862.3
65.2Chico ZapoteManilkara zapota63.863.669.863.6
63.9Lignum VitaeGuaiacum officinale94.752.445.463.3
63.7Siamese RosewoodDalbergia cochinchinensis51.949.964.488.7
63.0MgurureCombretum schumannii95.652.753.749.8
62.5Angelim vermelhoDinizia excelsa67.960.158.163.7
62.3VerawoodBulnesia arborea80.047.567.054.7
61.8Pau RosaBobgunnia fistuloides63.152.462.569.2
61.5MachicheLonchocarpus spp.57.958.665.564.0
61.2Horsetail CasuarinaCasuarina equisetifolia68.858.758.658.7
61.2ItinProsopis kuntzei68.853.357.565.1
60.2Grey BoxEucalyptus moluccana71.155.556.657.5
60.1AraracangaAspidosperma megalocarpon52.465.556.865.8
60.1Macassar EbonyDiospyros celebica69.253.258.859.1
59.9PurpleheartPeltogyne spp.53.863.160.962.0
59.6Black IronwoodKrugiodendron ferreum78.863.746.049.8
59.4SneezewoodPtaeroxylon obliquum66.254.454.163.0
59.4MarblewoodZygia racemosa54.268.958.855.6
59.1Rose sheoakAllocasuarina torulosa67.662.253.952.6
58.5JatobaHymenaea courbaril57.658.658.060.0
58.4Hormigo NegroPlatymiscium dimorphandrum57.960.755.359.5
58.3Gaboon EbonyDiospyros crassiflora66.251.659.256.0
57.0MoraMora excelsa49.159.658.260.9
57.0MoraMora gonggrijpii49.159.658.260.9
56.8BubingaGuibourtia spp.(tessmannii)51.556.863.355.6
56.8East African OliveOlea capensis57.854.658.156.7
56.3Pink IvoryBerchemia zeyheri69.445.751.159.2
55.8BelahCasuarina cristata97.148.644.233.3
55.5Texas EbonyEbenopsis ebano60.550.556.954.2
55.2TurpentineSyncarpia glomulifera59.046.955.559.3
54.9QuinaMyroxylon peruiferum47.051.258.862.6
54.5Gum ArabicVachellia nilotica67.049.649.651.8
54.3BoxwoodBuxus sempervirens60.852.753.749.8
54.0Santos MahoganyMyroxylon balsamum51.350.055.459.4
54.0Spotted GumCorymbia maculata49.761.452.652.4
53.7Blue GumEucalyptus globulus50.758.049.756.5
53.0Madagascar RosewoodDalbergia baronii58.235.162.356.2
52.8WengeMillettia laurentii41.154.056.659.6
52.5BrownheartVouacapoua americana40.054.956.158.9
52.1MutenyeGuibourtia arnoldiana34.957.456.958.9
51.8UrundeuvaAstronium urundeuva67.644.949.045.5
51.6Ceylon SatinwoodChloroxylon swietenia56.143.754.052.4
51.5KarriEucalyptus diversicolor43.263.746.952.2
51.3Argentine Osage OrangeMaclura tinctoria50.944.949.859.6
51.2MopaneColophospermum mopane72.839.241.451.2
50.5MoabiBaillonella toxisperma38.050.960.153.2
50.0Brazilian RosewoodDalbergia nigra59.841.649.848.7
49.8Red ashAlphitonia excelsa*40.158.849.451.0
49.6TatajubaBagassa guianensis36.558.745.358.1
49.6Yellow BoxEucalyptus melliodora62.741.944.649.3
48.8MerbauIntsia bijuga39.248.454.053.7
48.4Goncalo AlvesAstronium graveolens46.250.542.654.4
48.4LemonwoodCalycophyllum candidissimum39.947.856.949.0
48.1Black PalmBorassus flabellifer43.147.350.951.2
48.1BambooPhyllostachys spp.31.958.844.757.0
47.9KempasKoompassia malaccensis37.262.543.248.8
47.5Pignut HickoryCarya glabra45.647.251.345.6
47.3Lemon-Scented GumCorymbia citriodora40.750.949.647.9
47.0River SheoakCasuarina cunninghamiana42.435.248.761.7
46.8Live OakQuercus virginiana57.440.246.143.5
46.8PartridgewoodAndira inermis38.056.046.846.2
46.7Ceylon EbonyDiospyros ebenum51.942.147.345.7
46.5Panga PangaMillettia stuhlmannii34.847.748.355.0
46.1Burma PadaukPterocarpus macrocarpus45.842.351.444.8
46.0Osage OrangeMaclura pomifera56.133.947.346.7
45.9OvangkolGuibourtia ehie27.957.552.046.3
45.6OhiaMetrosideros collina43.447.446.245.5
45.6Prosopis julifloraProsopis juliflora56.135.542.048.8
45.6Shagbark HickoryCarya ovata40.044.951.645.7
45.4YellowheartEuxylophora paraensis38.050.842.150.6
45.3Mockernut HickoryCarya tomentosa41.946.348.844.3
45.2AfzeliaAfzelia spp.38.443.344.754.3
45.2PersimmonDiospyros virginiana49.141.444.645.5
45.1Lebombo ironwoodAndrostachys johnsonii55.931.847.045.7
44.9Amazon RosewoodDalbergia spruceana57.838.142.541.3
44.9TamarindTamarindus indica57.739.240.142.6
44.9ZebrawoodMicroberlinia brazzavillensis39.049.944.945.8
44.8EtimoeCopaifera salikounda35.141.052.950.3
44.7Black LocustRobinia pseudoacacia36.042.349.451.2
44.7BeliJulbernardia pellegriniana31.249.049.848.7
44.6TimboranaPseudopiptadenia suaveolens (= Piptadenia spp.)32.750.043.851.8
44.2Yellow GumEucalyptus leucoxylon52.935.140.148.5
43.9NargustaTerminalia amazonia37.145.944.847.8
43.8Afzelia xylayAfzelia xylocarpa42.239.743.349.9
43.6CanarywoodCentrolobium spp.32.045.048.548.7
43.5GarapaApuleia leiocarpa35.047.246.944.8
42.6JarrahEucalyptus marginata39.544.238.947.9
42.6DogwoodCornus florida45.939.341.943.2
42.5East Indian RosewoodDalbergia latifolia52.233.441.542.7
42.3AngeliqueDicorynia guianensis27.151.144.047.1
42.2Black wattleAcacia mearnsii36.143.944.544.4
42.2Tropical black sageCordia curassavica47.031.344.446.1
42.0GuajayviPatagonula americana35.139.453.740.0
42.0Cherrybark OakQuercus pagoda31.247.745.743.1
41.8Red BloodwoodCorymbia gummifera52.437.935.341.7
41.7River Red GumEucalyptus camaldulensis46.034.445.341.1
41.7MonkeythornSenegalia galpinii43.538.940.643.7
41.6RaminGonystylus spp.25.447.146.047.8
41.2BeefwoodGrevillea striata51.841.933.338.1
41.1Rhodesian TeakBaikiaea plurijuga64.223.129.347.9
40.8KeruingDipterocarpus spp.29.248.041.944.0
40.8Indian LaurelTerminalia elliptica49.936.636.340.3
40.7TambootieSpirostachys africana53.028.936.844.1
40.6BocoteCordia elaeagnoides42.935.741.542.4
40.6Canadian ServiceberryAmelanchier canadensis38.238.342.443.3
40.5Shellbark HickoryCarya laciniosa38.438.645.739.0
40.4Water HickoryCarya aquatica32.841.644.942.4
40.4OpepeNauclea diderrichii32.739.342.347.2
40.4Field mapleAcer campestre24.034.445.058.2
40.3LatiAmphimas pterocarpoides25.144.646.744.9
40.3Pau FerroMachaerium spp.41.731.244.843.7
40.2Peroba RosaAspidosperma polyneuron35.541.238.945.3
40.2Swamp White OakQuercus bicolor33.941.843.841.2
40.2ChanfutaAfzelia quanzensis39.334.239.347.7
40.1Sweet BirchBetula lenta31.045.142.442.0
40.1ZiricoteCordia dodecandra42.031.441.046.1
39.6MessmateEucalyptus obliqua*32.142.840.743.0
39.5African PadaukPterocarpus soyauxii41.934.142.239.7
39.5LyptusEucalyptus urograndis30.042.343.042.6
39.2AfataCordia trichotoma23.539.746.646.9
38.9Bitternut HickoryCarya cordiformis31.736.243.044.8
38.7TanoakNotholithocarpus densiflorus29.842.841.740.4
38.6Swamp MahoganyEucalyptus robusta26.142.344.042.0
38.5MovinguiDistemonanthus benthamianus26.835.847.544.0
38.5Burmese BlackwoodDalbergia cultrata72.131.827.223.0
38.5Queensland WalnutEndiandra palmerstonii35.133.135.949.8
38.5European BeechFagus sylvatica30.642.939.840.5
38.2Red PalmCocos nucifera40.333.131.447.9
38.1AfrormosiaPericopsis elata33.234.536.947.8
37.9Hard milkwoodAlstonia spectabilis30.840.229.650.9
37.5Andaman PadaukPterocarpus dalbergioides34.535.436.543.6
37.5RowanSorbus aucuparia35.829.243.541.3
37.3Yellow BirchBetula alleghaniensis26.441.441.640.0
37.3ParicaSchizolobium amazonicum26.441.441.640.0
37.3AmendoimPterogyne nitens37.935.839.336.3
37.1RengasGluta spp. Melanorrhoea spp.36.539.231.841.2
37.0SapeleEntandrophragma cylindricum29.735.239.743.2
36.7Rose GumEucalyptus grandis26.442.438.939.1
36.7Pear HawthornCrataegus calpodendron35.526.443.441.4
36.5Eastern HophornbeamOstrya virginiana39.534.134.637.7
36.4Scarlet OakQuercus coccinea29.535.740.140.4
36.3Hard mapleAcer saccharum30.637.239.338.1
36.3PecanCarya illinoinensis38.734.833.538.2
36.3European HornbeamCarpinus betulus34.535.439.935.3
36.2AndirobaCarapa spp.25.640.338.740.3
36.0Australian blackwoodAcacia melanoxylon24.344.637.237.8
35.9PheasantwoodSenna siamea31.531.430.050.9
35.9Mountain AshEucalyptus regnans25.441.934.342.0
35.8American HornbeamCarpinus caroliniana37.834.040.730.7
35.7Black sirisAlbizia odoratissima34.634.334.239.8
35.2Water OakQuercus nigra24.941.941.632.2
35.0European AshFraxinus excelsior31.236.137.135.7
35.0LebbeckAlbizia lebbeck28.037.333.541.2
34.7SissooDalbergia sissoo35.129.634.739.3
34.6Honey LocustGleditsia triacanthos33.432.536.336.3
34.5EbiaraBerlinia spp.26.932.239.639.3
34.4Willow OakQuercus phellos30.836.636.733.7
34.4MansoniaMansonia altissima27.131.141.637.9
34.4Turkey OakQuercus cerris25.131.141.540.0
34.3MakoreTieghemella heckelii25.230.740.840.7
34.3Pacific YewTaxus brevifolia33.926.037.739.6
34.2Slash PinePinus elliottii15.540.740.739.8
34.1UtileEntandrophragma utile24.733.937.340.6
34.0White OakQuercus alba28.335.636.635.5
34.0Longleaf PinePinus palustris17.940.735.741.7
34.0NarraPterocarpus indicus26.534.734.240.5
33.9Nutmeg HickoryCarya myristiciformis27.134.141.633.0
33.9White AshFraxinus americana27.735.137.135.8
33.8Norway mapleAcer platanoides21.130.341.842.1
33.7PyinmaLagerstroemia spp.22.731.034.646.2
33.6NyatohPalaquium spp.22.339.734.138.5
33.6Winged ElmUlmus alata32.533.036.532.3
33.5Tasmanian MyrtleLophozonia cunninghamii27.637.235.034.4
33.5American BeechFagus grandifolia27.334.636.835.2
33.4MangiumAcacia mangium30.031.935.036.5
33.2Sumatran PinePinus merkusii19.744.934.334.1
33.1Ocote PinePinus oocarpa19.746.036.330.2
33.0Pin OakQuercus palustris31.634.433.932.1
33.0English WalnutJuglans regia25.531.140.335.1
32.9TeakTectona grandis22.236.034.538.7
32.7AvodireTurraeanthus africanus24.432.138.236.2
32.6Indian Silver GreywoodTerminalia bialata28.639.231.131.4
32.6Laurel OakQuercus laurifolia25.336.335.233.4
32.5Black MesquiteProsopis nigra41.320.526.541.8
32.4KotoPterygota macrocarpa19.535.437.936.8
32.3Swamp Chestnut OakQuercus michauxii25.735.433.634.6
32.3Caribbean PinePinus caribaea23.135.232.538.4
32.3Western sheoakAllocasuarina fraseriana40.426.134.927.7
32.2Red OakQuercus rubra25.635.635.432.3
32.1Rock ElmUlmus thomasii27.730.436.533.8
32.0HububaliLoxopterygium sagotii21.337.236.033.4
31.8Black WalnutJuglans nigra21.033.736.036.7
31.7Green AshFraxinus pennsylvanica25.133.234.634.0
31.7MuningaPterocarpus angolensis28.624.035.039.2
31.6Nigerian pearwoodGuarea cedrata19.531.437.038.5
31.6BosseGuarea cedrata19.531.437.038.5
31.6Black OakQuercus velutina25.335.035.530.5
31.5Sweet CherryPrunus avium24.030.137.034.9
31.5Blackheart SassafrasAtherosperma moschatum22.837.135.930.2
31.3Pacific mapleAglaia cucullata21.035.432.136.7
31.3Alaska Paper BirchBetula neoalaskana17.038.833.236.0
31.2White SerayaParashorea spp. (lucida, stellata)18.337.431.937.2
30.9Sycamore mapleAcer pseudoplatanus21.928.034.938.9
30.9PaldaoDracontomelon dao21.735.433.133.4
30.9Western LarchLarix occidentalis17.038.131.536.9
30.7Red MulberryMorus rubra35.626.027.833.5
30.4Chakte KokSimira salvadorensis 25.329.435.231.8
30.4MangoMangifera indica22.433.531.034.8
30.4IrokoMilicia excelsa26.426.230.738.1
30.3Blue AshFraxinus quadrangulata27.127.133.733.4
30.3Black mapleAcer nigrum24.732.332.431.7
30.1Sessile OakQuercus petraea23.429.934.532.7
30.1English OakQuercus robur23.430.534.531.9
30.1Post OakQuercus stellata28.329.331.730.9
30.0Chestnut OakQuercus prinus23.631.632.432.6
30.0Tree of HeavenAilanthus altissima29.932.326.131.7
30.0Crab appleMalus sylvestris36.724.131.028.1
29.9Wych ElmUlmus glabra20.532.235.031.9
29.9ChinaberryMelia azedarach20.524.834.639.6
29.8DoiAlphitonia zizyphoides24.033.027.534.8
29.7Parana PineAraucaria angustifolia16.632.932.636.7
29.7African MahoganyKhaya senegalensis22.330.332.034.1
29.7SalmwoodCordia alliodora18.438.230.331.7
29.5KoaAcacia koa24.429.530.533.8
29.5White Cypress PineCallitris columellaris28.726.027.536.1
29.4Cedar ElmUlmus crassifolia27.729.032.928.1
29.4European LarchLarix decidua15.134.431.736.5
29.1Dark Red MerantiShorea spp.16.535.130.733.9
29.0Shortleaf PinePinus echinata14.035.331.835.0
29.0Red mapleAcer rubrum19.732.732.631.0
28.9West African albiziaAlbizia ferruginea21.231.428.734.4
28.9Loblolly PinePinus taeda14.036.231.034.2
28.8Khasi PinePinus kesiya13.635.930.435.4
28.8PearPyrus communis35.120.828.930.2
28.7New Guinea WalnutDracontomelon mangiferum18.733.530.432.0
28.6White MerantiShorea hypochra21.829.130.932.7
28.6Pond PinePinus serotina15.135.327.636.5
28.6TineoWeinmannia trichosperma21.431.131.730.2
28.5AnigrePouteria altissima20.431.528.833.1
28.4Algarrobo BlancoProsopis alba36.015.020.841.9
28.4Oregon White OakQuercus garryana34.819.923.735.3
28.2CoffeetreeGymnocladus dioicus29.327.624.531.3
28.1Black CherryPrunus serotina19.729.229.634.1
28.0Overcup OakQuercus lyrata24.927.630.429.1
27.9Hoop PineAraucaria cunninghamii15.234.329.632.4
27.9Douglas-FirPseudotsuga menziesii12.535.730.133.2
27.8MadroneArbutus menziesii30.823.124.332.8
27.6CucumbertreeMagnolia acuminata14.236.929.629.7
27.5SweetgumLiquidambar styraciflua17.532.730.129.7
27.3Oregon AshFraxinus latifolia24.326.230.728.2
27.3African JuniperJuniperus procera18.428.627.834.4
27.2ImbuyaOcotea porosa20.027.029.532.3
27.2Common LimeTilia x europaea14.134.129.830.7
27.1Virginia PinePinus virginiana15.129.931.531.9
27.1Red ElmUlmus rubra17.729.231.530.0
27.1New Zealand kauriAgathis australis14.834.630.328.7
27.1Southern Red OakQuercus falcata22.129.028.828.5
27.1Queensland MapleFlindersia brayleyana16.731.128.032.5
27.0CamphorCinnamomum camphora19.633.627.827.0
26.9Black AshFraxinus nigra17.531.830.427.8
26.8Honduran MahoganySwietenia macrophylla18.628.527.932.2
26.6TamarackLarix larcina11.832.727.634.4
26.6SourwoodOxydendrum arboreum19.430.427.629.0
26.6African WalnutLovoa trichilioides19.425.729.431.8
26.5Paper BirchBetula papyrifera18.831.629.626.3
26.5Norfolk Island PineAraucaria heterophylla13.134.728.030.3
26.2Monkey PuzzleAraucaria araucana7.733.634.229.4
26.2LimbaTerminalia superba13.629.930.131.2
26.2Western HemlockTsuga heterophylla10.732.526.834.6
26.0Table Mountain PinePinus pungens13.330.627.632.6
26.0IdigboTerminalia ivorensis17.426.128.731.7
25.9European alderAlnus glutinosa13.131.732.226.7
25.9DegluptaEucalyptus deglupta13.031.027.532.3
25.8Yellow MerantiShorea spp.14.230.627.930.5
25.7Sand PinePinus clausa14.927.427.633.1
25.7Port Orford CedarChamaecyparis lawsoniana11.832.929.528.4
25.6Cedar of LebanonCedrus libani16.928.628.428.5
25.5CerejeiraAmburana cearensis16.231.324.729.7
25.4Cape HollyIlex mitis22.825.125.728.1
25.3TornilloCedrelinga catenaeformis19.731.222.827.7
25.3SweetbayMagnolia virginiana16.632.725.726.2
25.2AburaMitragyna ciliata (=Fleroya)16.926.828.129.2
25.2Huon PineLagarostrobos franklinii19.125.726.129.8
25.1Bur OakQuercus macrocarpa28.518.725.727.4
25.0Cuban MahoganySwietenia mahogani19.226.025.329.5
24.9Southern MagnoliaMagnolia grandiflora21.227.126.525.0
24.8Light Red MerantiShorea contorta11.033.026.528.7
24.6Bigleaf mapleAcer macrophyllum17.528.325.127.7
24.6Radiata PinePinus radiata14.428.527.328.1
24.5Siberian ElmUlmus pumila20.421.426.629.8
24.5Peruvian WalnutJuglans neotropica19.820.926.431.0
24.5MyrtleUmbellularia californica26.723.022.326.0
24.5Red PinePinus resinosa11.232.525.928.4
24.5RubberwoodHevea brasiliensis19.925.124.328.6
24.3Pumpkin AshFraxinus profunda20.524.126.226.3
24.3Mountain HemlockTsuga mertensiana13.825.527.330.4
24.2London planePlatanus x acerifolia19.424.625.527.5
24.2Yellow silverballiAniba hypoglauca22.325.222.426.9
24.1Scots PinePinus sylvestris10.828.528.928.1
24.1American ElmUlmus americana17.025.728.225.3
24.0Grey alderAlnus incana15.730.428.021.9
23.8Yellow CedarCupressus nootkatensis11.627.626.229.7
23.5Pacific silver firAbies amabilis8.333.723.828.3
23.4Yucatan RosewoodDalbergia tucurensis25.420.723.623.8
23.3Pitch PinePinus rigida12.527.825.427.6
23.2CypressTaxodium distichum10.128.124.830.0
23.0Noble firAbies procera7.932.225.326.5
22.9Japanese LarchLarix kaempferi12.024.127.628.0
22.9Spruce PinePinus glabra14.227.224.026.1
22.8Sweet ChestnutCastanea sativa13.723.624.129.9
22.8Austrian PinePinus nigra13.331.121.325.6
22.8Water TupeloNyssa aquatica17.923.622.227.5
22.8HackberryCeltis occidentalis18.122.225.924.9
22.8SycamorePlatanus occidentalis15.727.623.124.5
22.7HollyIlex opaca21.220.324.025.4
22.7Yellow poplarLiriodendron tulipifera10.731.323.425.4
22.7Sitka SprucePicea sitchensis10.131.823.625.5
22.7Alder-leaf BirchBetula alnoides17.023.320.330.2
22.5Patula PinePinus patula10.928.627.323.3
22.5Fijian kauriAgathis macrophylla17.327.619.525.7
22.5Northern Silky OakCardwellia sublimis17.324.621.826.2
22.4East Indian Kauri Agathis dammara12.225.922.429.3
22.1MonkeypodSamanea saman18.621.221.826.8
22.1Spanish CedarCedrela odorata12.025.323.927.2
22.1Black SprucePicea mariana10.330.023.424.7
22.0Red alderAlnus rubra11.826.722.627.0
22.0Australian Red CedarToona ciliata14.325.624.223.8
21.9California red firAbies magnifica9.829.124.224.7
21.9Monterey CypressCupressus macrocarpa12.420.928.126.4
21.9Southern Silky OakGrevillea robusta18.221.325.322.8
21.8White firAbies concolor9.429.122.326.5
21.8Staghorn SumacRhus typhina13.822.223.727.6
21.6Southern RedcedarJuniperus silicicola12.221.721.531.1
21.6Cascara BuckthornRhamnus purshiana21.616.819.528.4
21.6PrimaveraRoseodendron donnell-smithii14.520.923.827.1
21.6Jack PinePinus banksiana11.426.022.926.1
21.5Mexican CypressCupressus lusitanica9.923.926.226.0
21.5Pinyon PinePinus edulis17.721.017.030.2
21.3Black TupeloNyssa sylvatica16.422.221.825.0
21.3California Black OakQuercus kelloggii22.717.319.326.0
21.2SassafrasSassafras albidum12.720.620.431.3
21.0Red SprucePicea rubens9.630.922.021.7
20.7Grand firAbies grandis9.630.219.623.6
20.7Horse chestnutAesculus hippocastanum16.718.622.525.0
20.4Maritime PinePinus pinaster7.423.324.826.1
20.4Western White PinePinus monticola8.128.522.322.7
20.4Eastern Red CedarJuniperus virginiana18.615.019.828.1
20.3Gray BirchBetula populifolia15.521.322.621.7
20.3Lodgepole PinePinus contorta9.425.721.524.5
20.3Giant ChinkapinChrysolepis chrysophylla14.923.425.117.7
20.2Dutch ElmUlmus x hollandica17.619.923.020.4
20.2Bigtooth AspenPopulus grandidentata8.127.820.624.1
20.0Okoume / GaboonAucoumea klaineana7.723.125.623.8
19.9Jeffrey PinePinus jeffreyi9.823.421.225.4
19.9Leyland CypressCupressus x leylandii8.217.528.725.3
19.8Ponderosa PinePinus ponderosa9.024.621.524.2
19.7Silver mapleAcer saccharinum14.221.020.123.6
19.6Queensland kauriAgathis robusta11.220.821.125.3
19.6Norway SprucePicea abies7.227.320.723.3
19.5RedwoodSequoia sempervirens8.822.920.226.2
19.5European silver firAbies alba5.922.422.027.7
19.5European AspenPopulus tremula7.227.420.322.8
19.4English ElmUlmus procera16.718.521.521.0
19.3American ChestnutCastanea dentata10.723.119.224.2
19.3Eastern HemlockTsuga canadensis9.822.420.124.7
19.2BasswoodTilia americana7.928.519.520.9
19.2Balsam firAbies balsamea7.726.819.822.4
19.1GuanacasteEnterolobium cyclocarpum9.223.119.324.6
18.9Eastern CottonwoodPopulus deltoides8.326.419.021.9
18.9EspaveAnacardium excelsum9.223.920.522.0
18.7White SprucePicea glauca9.425.119.420.9
18.7Limber PinePinus flexilis8.321.720.624.0
18.6Engelmann SprucePicea engelmannii7.426.420.420.0
18.4Pin CherryPrunus pensylvanica10.124.119.020.3
18.3BoxelderAcer negundo14.618.917.622.2
18.2Subalpine firAbies lasiocarpa6.625.318.722.0
18.1ButternutJuglans cinerea9.622.017.823.0
18.1Black PoplarPopulus nigra8.918.821.023.6
17.9Mexican alderAlnus jorullensis12.820.918.519.2
17.8Eastern White PinePinus strobus7.223.419.221.3
17.5Crack WillowSalix fragilis12.821.321.514.3
17.3Black CottonwoodPopulus trichocarpa6.624.119.019.7
17.3Incense CedarCalocedrus decurrens9.218.717.623.5
17.2BataiFalcataria moluccana8.323.318.618.4
16.9Nepalese alderAlnus nepalensis7.222.415.921.9
16.8Indian pulaiAlstonia scholaris*8.122.917.718.4
16.8Sugar PinePinus lambertiana7.222.218.119.4
16.6JelutongDyera costulata7.423.017.618.3
16.6White WillowSalix alba11.320.718.016.3
16.4Quaking AspenPopulus tremuloides6.622.018.718.3
16.3Alligator JuniperJuniperus deppeana24.39.613.917.6
16.3Northern CatalpaCatalpa speciosa10.922.721.59.9
16.0Cheesewood, emienAlstonia congensis (and A. boonei)7.919.917.119.1
15.9ObecheTriplochiton scleroxylon8.317.119.918.3
15.8Andean alderAlnus acuminata8.320.916.018.0
15.8Western Red CedarThuja plicata6.620.316.220.0
15.7Siam balsaAlstonia spatulata8.818.715.719.5
15.6Yellow buckeyeAesculus flava (octandra)6.621.716.217.8
15.2Black WillowSalix nigra8.318.017.017.4
14.4Atlantic White CedarChamaecyparis thyoides6.616.114.220.8
14.3CandlenutAleurites moluccanus6.419.215.815.9
14.2Balsam PoplarPopulus balsamifera5.520.114.217.0
13.6Gowen CypressCupressus goveniana11.39.718.315.1
13.4SugiCryptomeria japonica5.920.310.017.2
12.3Northern White CedarThuja occidentalis5.913.113.416.7
9.1PaulowniaPaulownia spp.5.49.210.611.4
3.7BalsaOchroma pyramidale0.47.03.24.1
0.0QuipoCavanillesia platanifolia0.00.00.00.0

My interpretation of the data

95.3*—The World’s Strongest Wood (with a great big asterisk)

Pintobortri (Pouteria eugenifolia)

With an astounding strength index of 95.3, pintobortri (Pouteria eugenifolia) earns the top spot among all woods. But I am not quite ready to hand over the top spot to this species without reservation.

While the estimated hardness is one caveat, the biggest issue I have with this wood is simply that it’s so obscure and not thoroughly studied. All the data is based upon a single source, so there’s no averaging or balancing to serve as a moderating force. You may be wondering, in practice, how often does one set of data on a wood species come in stark contrast to another dataset? All the time.

Let me present one such instance. Pintobortri’s best-in-class measurement of MOR at 37,560 lbf/in2 (259.0 MPa) is nearly identical to an African hardwood named congotali (Letestua durissima), which, according to one source, measures in at an impressive 37,270 lbf/in2 (257.0 MPa). The only difference is that congotali has more data points available (with lower values), which serves to paint a more reasonable, less extreme version of its strength properties. This is a phenomenon that I discuss at length in the video, Quest for the Hardest Wood in the World.

Honorable mention: There are a few other Pouteria species, most of which are probably just as obscure and unobtainable as P. eugenifolia, which have a very high strength index. Not wanting to clutter the list with completely unknown woods that are more-or-less repeats, I’ve only listed the highest-scoring member of the group. Notable runner-ups include asepoko (P. guianensis) with a strength index of 79.2, and P. egregia at 71.0.

80.3—The World’s Strongest Wood (without an asterisk)

Kaneelhart (Licaria canella)

With a scarcity of data in the top positions (especially Janka hardness data) we have to move a few notches down the list before landing on a wood without any sort of footnote or caveat attached to it. There, free from any dark clouds of doubt, we find kaneelhart (Licaria canella), with a very respectable strength index of 80.3. Each of its values are documented and accounted for, and come from multiple sources.

It’s worth noting that kaneelhart’s strength index is pulled down significantly by its somewhat subpar Janka hardness, so if it’s simply raw structural strength and rigidity that’s in question, kaneelhart certainly ranks very near the very top of the heap, even when other lesser-documented and asterisk-laden woods are included in the mix.

But another pertinent note to all the realists out there is that all of the wood species in the top three or four spots aren’t generally exported on a regular basis, and can be (very) hard to come by. However, the IUCN reports that each of the species in these top spots are listed as being of “least concern” with regards to extinction, with stable population trends. 

Honorable mention: Greenheart, sitting at a strength index of 68.8, is another wood with outstanding structural strength properties that’s brought down somewhat by it’s disproportionately low (yet still very good!) Janka hardness value.

79.8—The World’s Strongest Wood (you can actually buy)

Snakewood (Brosimum guianense)

Heretofore, nearly all woods at the top of this strength list have ranged in availability from challenging (kaneelhart) to nearly impossible (pintobortri). Yet still very high on the list is snakewood, sitting at a strength index of 79.8. Snakewood is an exotic hardwood that can still be found with a simple ebay search or a trip to a local specialty hardwood supplier (especially if they feature turning blanks or knife scales for hobbyist-oriented woodworkers).

Like all the woods listed above, there are caveats. The biggest in my mind is that the tree that yields snakewood is typically very small, and usually full of defects. So while snakewood is one of the strongest woods you’ll probably ever have in your possession, chances are that any pieces will be so small (not to mention expensive), the point will be moot. This is definitely not a structural timber—it’s far more often admired for it’s striking grain patterns and colors. 

Honorable mention: With a strength index of 78.1, katalox is another wood with decent commercial availability. It’s certainly available in larger sizes than snakewood, though there tends to be large amounts of sapwood, so wastage can be high.

70.4—The World’s Strongest Wood (you can actually use for its strength)

Ipe (Handroanthus serratifolius)

After filtering out woods for lack of availability, the next sieve that contenders must pass through is that of usable size. This is where our previous entrant, snakewood, falls short. When it comes to woods that are both commercially available and also found in respectable sizes, what rises to the top of the heap is ipe, with a strength index of 70.4. And closely allied to size is also affordability. It’s simple math: if a tree is large enough to be commercially viable, the wood is usually also less expensive when compared to other smaller, more specialty-oriented hardwoods such as snakewood.

Ipe is commonly used for decking and other exterior applications where durability and good weathering characteristics are required. The only caveat when using this wood for its strength is to use mechanical fasteners—especially when joining pieces of the wood that are intended to be outside in the elements. Ipe is notoriously difficult to glue (or at least, to remain glued together) in exterior applications. 

Honorable mention: Close behind is bulletwood and cumaru, both more or less tied at 69.8. Both of these woods can be found at flooring or decking dealers, and larger structural pieces are also not unheard of. In addition, all three of these woods have the added benefit of being highly rot resistant (but also troublesome in gluing!).

47.5—The World’s Strongest Wood (you might have in your backyard)

Pignut hickory (Carya glabra)

Statistically speaking, only about two thirds of those reading this will be from the United States or Canada, so my apologies to the remaining third for which this entry will seem out of place. You may have noticed that all the previous top positions have belonged to tropical hardwoods, so my goal with this category is to list a temperate species that readers might be familiar with—perhaps even in tree form. For this title, many hickory species hover near the top, but it is pignut hickory that statistically comes out the winner with a strength index of 47.5. 

It’s true that there are other North American species with higher values, such as black ironwood or Texas ebony, but these species only occur at the very southernmost tips of the United States, with their natural distributions being centered in much hotter climates—hardly what I would consider temperate-zone species. But many hickories (including pignut) are found firmly in the midst of the eastern United States, and even have a sprinkling of distribution northward into Canada as well. In these areas, hickory has a reputation as being one of the toughest woods around, and it’s well founded.

Honorable mention: It’s hard to believe that hickory beats out so many other worthy competitors found in America, but when multiple facets of wood strength are considered, pignut hickory tops even respectable hardwoods such as osage orange, black locust, hornbeam and hop-hornbeam. But when temperate European species are throw into the mix, the title goes to the freakishly strong iron birch (Betula schmidtii), with a strength index of 65.7. But its MOR index is an astounding, must-be-a-typo value of 89.6! (Another runner-up mention goes to Cornelian cherry (Cornus mas), reputed by Europeans in the ancient world to be one of the absolute strongest woods around, there’s unfortunately no studies or reputable data available on this wood to verify the claim.)

Sidenote: composite woods and other manmade materials

When a woodworker is looking at wood for strength purposes, a natural comparison might be to that of composite wood materials—basically, anything that combines some form of wood material with glues, binders, or other synthetic materials. The important thing to remember is this: what makes wood such a special material lies in its grain. The more a product takes advantage of the wood grain, the better it will perform.

There are two primary types of composite materials pertaining to strength wood grain.

  • Panel products that don’t fully leverage wood grain strength (instead emphasizing convenience and dimensional stability)
  • Laminated products that have a specific long axis of wood fibers, and therefore a specific axis of strength

First, let’s take a look at the data to have a point of reference. Most of these composite materials can be highly variable depending on which wood species they are derived from (such as plywood). Also, data for Janka hardness and crushing strength was lacking, so it is only a partial picture. Nonetheless, the averages of known values are presented in the chart below, and help to give a general picture to compare these products to solid wood.

Strength
index

Material Name

MOE
index

MOR
index

30.9LVL (laminated veneer lumber)42.219.5
23.9Glulam (glued-laminated timber)34.113.7
12.6Plywood15.99.2
11.6OSB (oriented strand board)14.09.2
11.0Hardboard9.013.0
5.4MDF (medium density fiberboard)4.26.5
1.6Particleboard2.01.1

Referring back to the two types of composite materials, those lacking wood fiber/grain, and those leveraging wood grain, a spectrum can be formed:

  • 1.6-11.0—Hardboard, particleboard, and MDF Composed with little to no true wood grain, instead using synthetic materials in combination with wood flour. The overall strength properties and screw-holding abilities are abysmal, as reflected by the strength index going as low as 1.6 for particleboard. However, the material tends to be rather hard and stable, providing a good substrate for veneer. Also, while strength properties are low, they are more or less equal in all directions. 
  • 11.6-12.6—Plywood and OSB Composed of larger pieces (or sheets) of wood with fibers intact, but with alternating or random grain directionality. Slightly better modulus of elasticity, and much better screw holding ability, reflected by the slightly higher strength index going up to an average of 12.6 for plywood. Still not up to the task of supporting long stretches of load alone, such as bookshelves.
  • 23.9-30.9—LVL and glulam Composed of larger pieces of wood with fibers intact and oriented along the same axis—the closest thing to solid wood. Because of the multiple laminations of wood, the effects of knots and other defects are minimized, and the layers of glue also contribute an appreciable amount of stiffness. LVL scores a 30.9 strength index, a lot of that coming from the very good MOE. Understandably very good at handling loads across longer spans.

LVL has been described as being even stronger than solid wood, a claim that is both true, but also must be qualified. LVL will generally be stronger than the source wood from which it is made—this is usually a construction wood like pine. Thus, in the search for the strongest wood in the world, composite products can only go so far, and while providing consistency and predictably, they are far from the top of the list.

But what about…

In lists like these, there are inevitable objections or interjections of “but what about…” I think if you take a look at the list above, you’ll find it very comprehensive. If there is a species missing, it’s because there was a lack of data in at least on of the primary strength categories.

I’m always open to new suggestions, but after searching through the literature I have available, what you see above is just about everything I have. If you have a suggestion, please include a source of data data with strength properties so I can give it a fair evaluation.

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Troy u

why does spotted gum have such a low bow score but high strength score?

Pulp Friction

I need to make bookshelves that won’t sag, or if they do slightly, won’t take a set. What’s cheap and available?

Kovacs K.

Please add a specific strength index – strength index / density (air dry density at 12% MC). It’ll be good to see the strength-to-weight ratio of each wood. A separate column for density isn’t necessary but it would be good to see, too (raw values, not normalized).

And, waddywood is missing from the list of woods.

Bill

I didn’t see Poplar? And – I’d also be interested in strength-to-weight ratios, as well as strength-to-cost ratios. Thanks for a great article.

donavan

so if i were building a dugout style cabin (where rot resistance would be a major factor) which is the strongest wood (that i can actually buy in the southern united states) would make logs of usable size (most sites recommend at least 8 inch diameter logs so things like texas ebony would be right out)

also amazing job, thank you for taking the time to compile all this data

Last edited 9 months ago by donavan
James

I love your site! Thank you so much for making it, it’s amazing!
Could you please implement the ability to filter by specific modulus? It’s MoE/specific gravity. You already have the data, just need to calculate this derived parameter! Would make things so much better!
MoR/specific gravity would be great too – I’m not sure what the technical term for that one is though.

Ted

I’ve been trying for a while to find definitive data on the wood with the highest strength to weight ratio. There doesn’t seem to be any. Everyone sites sitka spruce but as far as I can tell Douglas Fir is very common and a good deal stronger. So far Port Orford Cedar is the winner. Things get further complicated when you define strength to weight as MOR to weight or MOE to weight. Afterall, a wood that weighs 1 pound³ with a MOR of a million is useless if its MOE is 100. Wings would flop and soundboards wouldn’t resonate.… Read more »

Ted

Finally! Not one but two fairly obtainable woods that beats Sitka in MOE. As you new, I had found some woods stronger but none stiffer. As always the leaders are somewhat scarce and obscure. But a hardwood, and an ash no less, coming out of Australia. That’s quite a delight. Australian woods are some of the easier woods to get as far as shipping price and foreign export. Noble Fir will be the top for my next guitar. I know for me at least, this is going to have a huge impact. Not to mention piano luthiers and DIY Sailplane… Read more »

Ted

Okay, I wasn’t aware of this. Thinking back, it should have been obvious that elasticity would change in relation to the grain. I have a whole library section readying itself in my head right now. But, before I go on I wanted to bounce some things off you. Particularly in the areas of MOE and, what I’m now discovering in the work you cited, Modulus of Rigidity. This is very expansive for me mentally and at the same time confusing. I had it in my head that MOE was how much force it took to bend an object. And your… Read more »

Ted

I feel like a half wit. I never considered there were different meanings for MOE for metal and wood. Your citation of ASTM D143 was very helpful. I went back and did some more research. All of wich lead me to a very obvious place in the article you cited that I missed. I’ll come back to that. This article shows a test in ASTM D143 called static bending that is used to find values for MOE and MOR- https://www.researchgate.net/figure/Determination-of-static-bending-strength-of-a-wood-specimen-Adapted-from-Esteves-2006_fig7_279900105 As it turns out Modulus of Rigidity is another name for sheer Modulus. Back to the obvious part. It says… Read more »

Ted

Continuing from where I left off and what you had said about woods not being nearly as stiff across the grain. Its interesting to see how Engelman, though not as stiff as sitka, seems to be much stronger across its other two axes than sitka and most other woods. Sugar pine and not surprisingly, white ash. This makes the red ash we had talked about earlier seem even more promising. You had said that Sitka was a star because of its stiffness across all axes and to keep in mind pacific silver and noble fir might fall short in those… Read more »

Ted

Since your talking about old growth vs second growth, that reminds me. In the wood handbook pdf. link you posted. The MOR for old growth vs young growth is 69,000/54,000 kPa. The MOE is 9.2/7.6 GPa! That’s a crazy difference! I think what your saying is Sitka will be stiffer than pacific silver because sitka is usually harvested from old growth or allowed to grow for a longer period in plantations because they know its solely used in instruments, planes, and ship masts. Whereas any pacific silver fir you find is likely to be plantation grown and intended for studs?… Read more »

Ted

Well, the pdf you cited says they tested there own samples for MOE in 2021. The values are still pretty close to yours. Maybe fir is so prevalent that we are still harvesting from forests? I’m not an expert on forests but perhaps some woods are affected by plantations less than others because they can still be harvested naturally.

Ted

The link you sent. The one that has a few radial and tangential MOE values. The bottom of the pdf, very last page says “March 2021 forest products laboratory”. It doesn’t specifically say “we did these tests ourselves”. But, directly after table 5-2. Under Tamarack. For c. “Modulus of elasticity measured from a simply supported, center loaded beam, on a span depth ratio of 14/1.” Directly below that is says “values of side hardness for the true hickories are from Bendtsen and ethington (1975)” That leads me to believe any other values that they didn’t test themselves would have also… Read more »

Ted

Republications! I originally downloaded the whole book in pdf from your link. Then you said how the book has been out for decades. I found a bunch of revisions over the years. It turns out the book was issued in 1935 and had 7 more revisions since then. I compared a bunch and apparently after all those revisions there was never any retesting done. It does gives a list of all the things revised but they are all additions. I just want to make sure I’m not living in some fantasy world that sees me assuming some woods are stronger… Read more »

Ted

I know I’ve beaten this to death. I was just trying to figure out exactly when the figures in the database can be used in the real world. I’m just going to assume that the figures can be used for any wood harvested from a naturally grown tree of sufficient age. Obviously you already stated the source of your technical data. It’s up to the reader to take into account the year the data was collected and from what range of samples it could have come. Wood already has a very wide range of values from tree to tree within… Read more »

Amer Kloster

so i make a lot of wooden swords, and i always strive towards more durable designs, what is the best hardwood for a sword blade?, i always had problems with splintering Ash and White Oak blades, but i recently tried Ipe, which seems a lot better, might there be any other hardwood that is great against blows from other wooden swords across the grain?
Kind Regards, Amér from Denmark

Patrick Brennan

Perhaps look for woods with interlocked grain, irregular grain, “feather crotch” – since wood splits along the grain, these might be better. Woods with high shock resistance? I could imagine a sword of a softer wood, with a layer of stronger wood along the impact edge; Katalox over persimmon perhaps…..sounds like fun !

Hope this helps

Patrick

Carla Kelly

Your mention of Ipe caught my attention. I’ve spent years testing hard woods to find those that we in the African drumming community can use for dundun sticks. They are often used against the 1/4″ (or larger) steel rings that secure the drumheads to the shells. It doesn’t take very long for them to start splintering, because it’s not hardness that makes them good, but toughness. Ipe is the wood that we finally settled on. I had tried all manner of ebonies, rosewoods, hickories, maples, ironwoods, lignum vitae, oaks, etc., but Ipe was the one that didn’t break down against… Read more »

Amer Kloster

thank you for the advice!, drumsticks are a great comparison

gabe

Where can I find references to mor of iron birch?

gabe

thank you!

Christopher M Durante

Since wood densities can very dramatically, it might be beneficial to include a tidbit about strength to weight ratio. In making baseball bats, I’ve noticed that birch performs better than ash at the same densities when it comes to wood bat durability even though their average density is different on the site.

Hayden Fox

Super thankful for this article, I was wondering if you had a reference for the highest strength to weight ratio on these woods?

Eric S

Which type of strength would be most applicable to the ability to hold a screw and resist tearout?

Matt

I would say a combination of Janka hardness and MOR, with MOR being more important.

Jeff S

Fascinating read! I make skinners out of the hardest woods in the world to cut off waste paper from parent rolls at the paper mill I work at. I have made them out of Lignum Vitae, Snakewood, Quebracho, Black Ironwood, African Blackwood, Kingwood & the last one I’m working on Pink Gidgee. Only the hardest woods will work because there’s a lot of force involved while cutting through the paper. These rolls are around 131” and are converted into toilet paper, toweling & napkins. I’ve broken lesser woods over the years right up to Vera wood. So as a tool… Read more »

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Steve C

I expected/wanted to see Tzalam in there. It’s not Cumarú or Ipe but it’s pretty solid, used in flooring, etc.

Hope

Have you considered impact strength? Some types of wood like Lignum Vitae or black ironwood which are very strong in static bending or compression tend to break more readily in impact applications compared to weaker woods like ash or hickory. See the following US Forest Products Labratory study comparing impact strengths of various American wood species: https://naldc.nal.usda.gov/download/CAT86200473/PDF Keep in mind the difference between “work to proportional limit” and “height of drop causing failure”:   Work to proportional limit is how much energy is needed to make the piece of wood start to fail   Height of drop causing failure is how much… Read more »

Lawrence

In Australia there has been extensive testing of the local timbers with regards to the impact value (called Izod value) for timbers. A complicating factor is how the impact value changes with seasoning, Some timbers decline in value, others increase. Spotted gums (used for tool handles) values are 20 Joules (J) unseasoned 24 when seasoned. Grey Ironbarks values are 24 J unseasoned to 27 J when seasoned. Some of the Wattles also exhibit increased impact strength, Black Wattle is 39 J! Radiata Pine a local non-native species has decreasing impact strength: 12 J unseasoned and 6.9 J when seasoned. Grey… Read more »

Robert Danforth

You have Katalox right up there with snakewood and is available in much better sizes. I do not see Camelnut and though I have seen photos of the trees, I have not seen the woods. An arrangement by color might be interesting as example Wenge, Katalox, and Gabon ebony.

Robert Danforth

Sorry I was thinking camelthorn. Many videos of trees I believe they said were Camelthorn along the dry riverbeds in Namibia that looked very substantial but of course, were in the National Park there, but watching I get the same feeling I got watching Capt. Nemo fighting the Giant Squid. It is supposed to be scary, But I am looking and thinking “mmm Steaks!”

Vince

Fantastic work! I was entralled and then exuberated to find that my whole reason coming to this site was to see if my felled Pignut Hickory Tree was worth the tool wear to incorporate into some of my black cherry and Red Maple projects. Turns out it owns a category. I’m now decided. Thank you.