NOTE: Wood weapons must have roughly similar qualities to train, one against the other. For example, using a black locust bokuto against a verawood bokuto would be foolish.
Blackbutt (Eucalyptus pilularis) – Tim Bathurst describes Blackbutt with a pale brown heartwood, sometimes with a slightly pinkish tinge. It’s sapwood is distinctively paler. With a Janka rating of 1984, it is harder than either hickory or purple heart. Tim Bathurst reports, “I have made both a Naginata and a Nagamaki out of Blackbutt, it is a beautiful wood that is easy to work and polishes well.”
Blackwood (Acacia melanocylon) – There are many wonderful acacia woods in Australia. This is the first that I’ve gotten a report on, from a top-level practitioner of a koryu. Blackwood is reported by a woodworker as having ‘a mind of it’s own. Talk about buckle and bow. Blackwood is one of the World’s great movers.’ This means it must be well-seasoned.
REPORT OF KORYU PRACTITIONER: Blackwood is extremely resilient to torsional stresses, and is impact hard. However, it does store impact stress, but unlike sunuke and more tangibly ebony, blackwood tends to have a mixture of fine and course straight grains. This makes the possibility of fine splintering (feathering, something I’ve encountered with ipe) more likely than the weapon cleanly snapping, or as ebony is famous, stored stress detonation. Blackwood is well-suited for more massive weapons such as naginata and yari, but not as good for bokuto or bou, as the larger diameter weapons can help spread the impact area rather than some of the sharper angles of the smaller ones where impact can tend to splinter the edge.
Black Locust (False acacia) – common in the Eastern United States, considered an invasive species in parts of Europe. It is common in the Netherlands. It is very rot-resistant. It is one of the hardest woods in North America, but it is prone to splitting and has frequent knots. When harvested young, these problems are minimized. It can be a remarkably attractive wood, with green and yellow coloration. It is used a lot in boat building. One commentator wrote: “The physical properties of black locust are nearly identical to purpleheart. The properties of black locust and osage orange are similar to hickory, except that hickory isn’t very stable (shrinks and swells a lot with moisture).” It is hard to get lumber from the black locust tree, due to a very gnarly grain, knots, and open cavities in the wood. Therefore, it is imperative to get fine/straight-grained wood. Warning: The bark is poisonous, so debark before milling.
I’ve used a black locust naginata. It is alive (more so than jotoba) and quite tough. Feels similar to kashi when struck, but it is although it looks nothing like it. The weapon had dents from very hard usage, but no splintering. It is light in weight, like hickory – perhaps even lighter.
Another informant states: “I decided to try the “Bokken Bashing” method, and take a cutoff scrap to a very large, very old tree in my backyard. It was a draw – only minor denting, and no cracks – and this was only a cutoff, roughly the length of a bokken (and much thinner at the tip).” ALSO “I let one of the yudansha go to town on a reject bokuto of black locust. He’s probably the hardest striker in the dojo, and his impact hickory bokken put a couple light dents into it while actively trying to break it. It’s actually impressive, given how light the wood feels, particularly compared to jatoba.”
On the other hand, I received this report from a practitioner of Kashima Shin-ryu, a system that has very powerful strikes of weapon upon weapon, among the most powerful I’ve ever seen in any ryu. “For our incredibly heavy impact it is just not strong enough: it dents, then splinters. In normal use a bokuto would last me ¾ months, against a good kashi bokuto.”
- Bending strength – 18,761 psi
- Maximum Crushing strength – 9259 psi
- Shearing strength – 2282 psi
- Static bending – 7840 psi
- Work to Maximum Load – 15 in-lbs./in3
- Janka hardness – 1560 – 1700
Hickory – In America, weapons-grade hickory is very hard to come by, as the best is bought up by tool-handle makers. Kingfisher Woodworks specializes in weapons of this wood, because among American woods, it is the best in terms of a combination of high bending strength, stiffness, hardness, and resistance to shock. Most important, it resists suddenly applied loads very well. I have a number of hickory bo and bokuto. It is an excellent wood – there is no doubt about it, and has one of the best combinations of qualities of any easily available wood. Interestingly, the toughest hickory wood is produced by fast grown, wide-ringed trees. The grain tends to lift a little bit, and it, thus, has a rough feel in the hands. Unlike kashi, which tends to get brittle with age (this can, however, be staved off with proper oiling), hickory will maintain it’s flexibility and strength far longer. I have not liked the hickory weapons that I’ve personally handled, however. It is relatively light – I prefer a heavier weight.
- Bending strength – 16,464 psi
- Maximum Crushing strength – 7379 psi
- Shearing strength – 1215 psi
- Static bending – 7840 psi
- Work to Maximum Load – 19-20 in-lbs./in3
- Janka Hardness Scale – 1820-2460 (NOTE: Hickory has quite a range).
Hornbeam (water beech, ironwood, blue-beech) – A fine wood, with a beautiful creamy color. One of the many woods called “ironwood.” It is difficult to work. I’ve used one bokken made of European hornbeam (Carpinus betulus). It feels great in the hands – medium heavy, and among the most “alive” woods I’ve ever used. It is definitely hard, takes sheering forces well, and is almost exemplary for practice weapons. However, it does dent with hard impact. The dents are not deep and do not feather, but this is a negative quality.
European Hornbeam (Carpinus Betulus)
- Bending strength – 18,011 psi
- Maximum Crushing strength – 7320 psi
- Shearing strength – 2204 psi
- Static bending – 7840 psi
- Toughness – 311 in-lbs.
- Work to Maximum Load – 17 in-lbs./in3
- Janka Hardness Scale 1632
Ironbark – This is an Australia tree, a eucalyptus, with a deeply furrowed bark that is fire resistant. The wood is very dense and fine grained, and very resistant to rot. It is very hard to work and can easily damage tools.
I know of one woodworker who use to provide bokken-like weapons for mounted police using this wood. He told me that the wood was excellent in all parameters. There are a lot of sub-species. That which I’ve seen is not a very attractive wood – it was a grey tan color. Photographs of red ironbark, however, show a beautiful wood, with a dark red heartwood, and pale yellow sapwood. Among the various Ironbarks are several varieties that all go by the same name, plus black ironbark, brown mallet and grey box.
I received the following commentary on red ironbark (Eucalyptus sideroxylon):
The red ironbark is fantastic if you don’t mind the weight. The bokkens I made weighed in just shy of 1.1 kg. Admittedly I was aiming for heavy and it should definitely be possible to get it down to closer to 0.8kg with a slimmer profile, without sacrificing durability. I don’t have a weight for my suburito other than “definitely more than 2kg” since that’s what my kitchen scale tops out at!
In terms of feel, the best word I can find is “solid”, but in a somewhat smooth fashion. It quietly absorbs strikes and continues on its merry way without much fuss. To some degree that does hide ones mistakes, for good or bad. Coming up against lighter weapons (i.e. just about all of them), the need for speed on the other hand does very much encourage proper handling. The only thing I didn’t appreciate about the wood was while working with it – the cross-grain can run very deep and if not careful it was easy to lift out a chunk of wood you really didn’t want gone. Minor complaint, and probably more a testament to my lack of skill at the time!
On a contrary note, Tim Bathurst writes regarding red ironbark: The problem with this wood is that the shock of impact transfers straight through the timber and into your hands.
- Bending strength – 25,113 psi
- Maximum Crushing strength – 12,223 psi
- Shearing strength – 2800 psi
- Static bending – 7840 psi
- Toughness – 250 in-lbs.
- Work to Maximum Load – 17 in-lbs./in3
- Janka Hardness Scale – 2862
- Bending strength – 25,480 psi
- Maximum Crushing strength – 13,328 psi
- Shearing strength – 2827 psi
- Static bending – 12,642 psi
- Toughness – 361 in-lbs.
- Janka Hardness Scale – 3200
- Bending strength – 20,384 psi
- Maximum Crushing strength – 11,074 psi
- Shearing strength – 2950 psi
- Static bending – 11,956 psi
- Toughness – 191 – in-lbs
- Janka Hardness Scale – 3244
Jotoba (also known as “Brazilian Cherrywood – Hymenaea courbaril) – another beautiful wood, the color ranges from brown, to a rich orange-red. It is quite hard and flexible. It is not as dent resistant as kashi, (but more so than either hornbeam or white sirus), but does make quite strong weapons. Associates of mine what been using it for large naginata, and with the exception of the denting on powerful impact, they hold up well. When well oiled, they become more dent resistant. Caution: Only use the heartwood – the sapwood is far less durable.
- Bending strength – 19.032 psi
- Maximum Crushing strength – 9349 psi
- Shearing strength – 2543 psi
- Static bending – 11,662 psi
- Toughness – 225 in-lbs.
- Work to Maximum Load – 16 in-lbs./in3
- Janka Hardness Scale 2820
Kashi (shirogashi, akagashi) – Japanese evergreen oak is the standard for Japanese weaponry. This may be an accident, but the Japanese archipelago just happened to have a wood ideal for practice weapons. It is flexible, rather stiff, impact resistant and impact absorbing, resistant to sheering force and to denting. It is less flexible than hickory and more dent resistant. One negative quality is that the sap tends to dry out. You must regularly oil kashi or it gets increasingly brittle. In addition, as it ages, the grain tends to separate. Genuine kashi from Japan is marvelous for weapons.
There is some variation between the now rare kashi grown on the main island of Honshu and that which is more common grown on Kyushu. Honshu, with its more severe and varied weather, produces wood that is somewhat denser, whereas Kyushu kashi is somewhat lighter. The Honshu would, being denser, is more resistent to denting whereas, according to one of the master craftsmen in Japan, Kyushu kashi, being lighter, is more flexible with straighter fibers.
It has been my observation that the quality of wood in Japanese weaponry using kashi has deteriorated for some time. Genuine red oak is very rare. According to Seido’s Jordy Delage, shirogashi (white oak) made weaponry, using Japanese oak in Japan, are made by four craftsmen.
A number of Japanese weapons fabricators are using Taiwanese or mainland Chinese (particularly Manchurian) kashi – it is both more brittle and lighter. I have fabricated some weapons from Japanese oak (I found a supplier of planks in Nerima ward in Tokyo) – beautiful shirogashi. This was thirty-five years ago, however, and I do not know if it still is extant.
Per one of my informants reports that Chinese also favored kashi for both spear shafts and staves, specifically Quercus glauca, which they referred to as Blue Oak (chou 椆 ). A number of other businesses selling Japanese-style weaponry are using wood from China or Taiwan, and it is my observation that the wood is lighter, more porous and brittle – it does not have the singular qualities that make Japanese evergreen oak such a marvelous wood. This is less a problem when one can walk into a shop and handle the practice weaponry directly – it is more problematic when one must order at a distance.
All kashi (Japanese oak) are from the same sub-genus – Cyclobanlanopsis. All are evergreen oaks. There is another common Japanese oak, nara, (quercus glandulifera, sub-gen. lepidobalanus or quercus Mongolica) that is not suitable for weaponry, although it does make fine furniture. I am going in such detail for two reasons: I’m aware of some makers of Japanese weaponry who have confused the two woods, and are either making weapons out of nara – which the Japanese never did – or dismissing Japanese oak based on using the wrong wood. I have listed the species of kashi below. Kashi has been transplanted to Europe and America for almost 150 years. It is very possible that there are local supplies of the wood outside Japan, unrecognized. Furthermore, if one takes the long view, knowing the species, someone (hint) may acquire some trees and grow one’s own – locally. Finally, knowing the sub-genus, you may be able to find other species in your locale with the same properties as the Japanese Cyclobalanopsis.
- Akagashi – Quercus acuta
- Arakashi – Quercus glauca
- Hanagagashi – Quercus hondai
- Ichiigashi – Quercus gilva
- Shirakashi – Quercus myrsinaefolia
- Tsukubanegashi – Quercus paucidentata
- Urajirogashi – Quercus stenophylla
Lignum Vitae – This is the hardest wood in the world. Only the heartwood is suitable for weapons – the sapwood is brittle. I have never used this wood for naginata. My lignum bokuto have a beautiful variegated color of browns and chocolate. It is “self-lubricating,” with a waxy resin inside the fibers that keeps it very strong. It was once used for bearings when a metal bearing burned out in a ship’s engine. The grain has a natural lamination, in which it reverses in 1/4-inch strips, with a herringbone pattern of internal lines. It is wonderful for impact – it absorbs a tremendous amount of shock that is not transferred to the hands. It does sometimes “check” – what this means is that the lengthwise “strips” of grain that I mentioned, separate, particularly in dry or variable environments. I’ve not seen this in the consistently moist Pacific Northwest. It is quite heavy – in fact, it doesn’t float. It has a wonderful warm smell. Lignum from the “Caribbean Rim” (Northern South America, Florida and the Islands is an endangered species and thus, not only is it hard to find in any length, but unless you can get some proof that it is old wood, cut before this endangered status, you are participating in the destruction of a species that should be preserved. Reportedly, Argentinean lignum vitae, almost identical in properties, is still relatively common, and is allegedly being well managed in Argentina. At any rate, the properties of verawood are so close that there is no need to get lignum weapons, unless you are lucky enough to find old wood – salvaged or laid away in storage before it was placed on a protected list or a legitimate source from Argentina.
- Maximum Crushing strength – 11,172 psi
- Toughness – 162 in-lbs.
- Janka Hardness Scale – 4200 -4500
Pyinkado (Xylia dolabriformis) – this is a very strong, very dense and hard wood from Southeast Asia. The Katori Shinto-ryu group of Vietnam has been making weapons with this wood and speaks very highly of it. The wood is sometimes referred to as “Burmese Ironwood.”
- Janka Hardness Scale – 2600
Sydney Red Gum (Eucalyptus camaldulensis) – This is a beautiful wood, with a red to reddish-brown heartwood, and paler sapwood. It has a Janka rating of approximately 1800, making it about as hard as hickory. Tim Bathurst writes: “A stunning red wood that works well and also holds of good polish. It is prone to fiddleback which can leave some gaps in the grain.”
Spotted Gum (Corymbia Maculata) – this Australian Eucalyptus is sometimes known as Australian Hickory. It is the most common wood used for tool handles. The heartwood is pale to dark brown or chocolate, with a distinctively paler sapwood. One report I’ve received states, that “jo made from spotted gum are fairly dense, and compress with impact. I’ve had varying reports regarding splintering: essentially, “similar to white oak, although not quite as durable.”
Tim Bathurst writes: Spotted Gum is my first choice for making weapons; it is readily available, sufficiently hard to withstand impact training and still flexible enough that it absorbs much of the impact so it doesn’t jar your hands. Spotted Gum is used for axe and shovel handles which is a good indication of its qualities.
Be mindful of “fiddleback,” these are irregularities in the grain pattern that can add some beautiful patterns to your wood but also make it tricky to work. Sometimes it will give you some gaps in the grain which may impinge on the integrity of the weapons’ strength. I have made a few Naginata with this feature in the shaft and none of them have broken yet although I would be less happy if it was to occur in the blade section. Spotted Gum has a natural oiliness to it which gives it great durability and it polishes nicely.
- Bending strength – 19,356 psi
- Maximum Crushing strength – 9945 psi
- Shearing strength – 2204 psi
- Janka Hardness Scale – 2185
Verawood (Palo Santo) – This is sometimes called lignum vera, or greenheart (there is a specific wood by the latter name). Vera wood has qualities very much like lignum vitae, but it is not endangered. The feel is a little different – you can feel the grain in your hands a little more. It, too, absorbs force wonderfully. The wood is dangerous to work – the dust is corrosive to the skin. I do not know if this is a genuine acid/base or poison, or if it makes an allergic dermatitus. It cannot be worked without protection – both for your skin and your lungs. The sap, too, has a peculiar smell – it is hard to describe, but it causes an allergic reaction among many. Therefore, I’ve had all my weapons coated with Varethane. The wood starts with an olive color and gets progressively darker. I’ve had bokuto, nagamaki and bo by this weapon. The bo finally broke. The break was at about a 45 degree angle -it did not splinter. One thing about vera – it makes a very flexible bo. With kashi, for example, I could cut full-force and stop the weapon one millimeter from the body of the opponent. With my verawood bo, I had to have about 10 centimeters distance, because it whips! This is a wonderful trait for a bo, but without care, you can really injure your partner. I would love to make a spear out of verawood. Admittedly, it is quite heavy, but it is possible that it would make an ideal spear, with both whip and a lot of strength. Janka Hardness Scale – 4000 – 4500