Treetom
ArboristSite Guru
Nice pics. Never thought the 'ol piss elm was much good for anything. Good luck, whatever you end up building.
Milling a hunk of chinese elm
- Thread starter sleddude5
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MCW
Somebody's talking crap here & it ain't the tree!
We don't have Jarrah where I am but do have species like Red Gum, Pink Gum, Mallee and such. The hardest dead wood I have ever cut was an old River Box. It also had some termite dirt in it to make matters worse. I actually gave up as it took 3 chains to drop it then 1 chain per round. It was also the densest wood I have ever lifted - felt like lead.
I'm not sure if Chinese Elm is really tough as far as janka hardness etc but this is getting up there with the toughest green wood I've ever cut. Hard to explain as not tough as in "I can't hammer a nail into it" hard but just really difficult to cut. I have cut down a few green Eucalypts in people's yards that have been super tough like steel but the chain has never felt like it just wants to "bounce" out like in this Elm log
The few references I could find to Chinese Elm Janka dry hardness rates it between 1200 and 1350 lb which puts it in the area of White Oak, American Elm and American Beech. Just by way of comparison Hickory (pecan) is rated at 1820 lb Janka Harness.
Jarrah's dry hardness is 1910 lb but is considered soft compared to other Aussie hardwoods. At 1300 lb Janka green hardness, jarrah is the softest wood I usually get to mill.
In comparison Spotted Gum is 2200, Queensland Box is around 3000 right up to stuff like Gidgee which is ~3800.
My understanding about CS cutting is straight hardness is just one factor that affects cutting speed. Because CS cutting involves a considerable amount of fibre tearing, the fibre strength and elasticity are important. Timber Like Aussie Karri is not all that hard (2040 lb) but it has very high tensile strength fibres so cuts more like a 2500 hardness timber. In contrast some really hard woods are quite brittle and so do not feel as hard.
The other factor is silica uptake of the tree. The silica blunts chains quickly but is not reflected in the hardness. An example of that is a rare tree called Tuart. It has a Janka harness of 2500 lb but it can draw up so much silica that is feels like cutting stuff harder than Queensland Box.
BTW here is an interesting table with a range of hardnesses although it contains only a few Aussie hardwoods. http://ejmas.com/tin/2009tin/tinart_goldstein_0904.html
Jarrah's dry hardness is 1910 lb but is considered soft compared to other Aussie hardwoods. At 1300 lb Janka green hardness, jarrah is the softest wood I usually get to mill.
In comparison Spotted Gum is 2200, Queensland Box is around 3000 right up to stuff like Gidgee which is ~3800.
My understanding about CS cutting is straight hardness is just one factor that affects cutting speed. Because CS cutting involves a considerable amount of fibre tearing, the fibre strength and elasticity are important. Timber Like Aussie Karri is not all that hard (2040 lb) but it has very high tensile strength fibres so cuts more like a 2500 hardness timber. In contrast some really hard woods are quite brittle and so do not feel as hard.
The other factor is silica uptake of the tree. The silica blunts chains quickly but is not reflected in the hardness. An example of that is a rare tree called Tuart. It has a Janka harness of 2500 lb but it can draw up so much silica that is feels like cutting stuff harder than Queensland Box.
BTW here is an interesting table with a range of hardnesses although it contains only a few Aussie hardwoods. http://ejmas.com/tin/2009tin/tinart_goldstein_0904.html
I'm with you...Beautiful grain,,and beats cutting it up into firewood..I see where if it does warp,,you can cut it up in short pieces,,and make alot of things with it still...
BlueRider
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This makes me think that something has been mistakenly identified. American elm (ulmas americana) is much softer than white oak but red elm (ulmas rubra) is comperable to white oak, also it is common for the picturesqe trees lineing many streest to be red elm yet most people think of them as iconic and therefore they must be american elms. The lumber from siberian elm (ulmas pumilia) looks almost exactly like red elm at a glance but it is slightly softer. this also leads to siberian elms often being confused with american elms. then there is the smell. all three smell like a barn yard when you cut them so tis leads to people calling all three piss elm... ahh latin is a wonderful tool.
in my experiance chinese elm (umas parvifolia) is much harder than either american elm or red elm and would be comperable to hickory in hardness.
the part about the fiber strength is probably more relivant than janka hardness because it will determine how a wood will work relative to wood working. though I suppose it is truely a combinatin of the fiber strength and hardness that determine how suitable a particular woood is for making something like a chair. It is for this reason that I am partcularly fond of Chinese elm. It is very tough and has performed superior to hickory for me in use as a handle wood. when using it for furniture I can make parts with smaller cross section and not wory about them breaking or having excessive flex.
jlpoole
New Member
The wood you have photographed looks very much to be Siberian Elm (the burls of which are used in Bentleys and Rolls Royce), not Chinese elm. I had two Siberian Elms in our parkway and had them milled up. I'm going to be milling Chinese Elm for the first time next week. In Southern California, Chinese elm is considered a trash tree and highly invasive. I'll e interested to see if the heart wood of the trees I'll be milling will bear anything like their cousins Siberian Elm and American Elm.
qbilder
ArboristSite Guru
Lots of folks confuse Chinese & Siberian elm, or consider the two the same thing. To be honest, i'm not sure I would know the difference. I have Siberian elm that ranged from chocolate brown walnut color to a blonde similar to birch. Never know til you're in the log. Siberian elm is considered invasive here. I have no idea if Chinese elm is here or not, or if I could even tell the difference.
There's an elm that I sometimes cut in Ohio that grows next to streams & in river bottoms. The old timers call it "piss elm" or "bobber elm" because it stinks and the bark is corky enough that it makes good fishing bobbers. It's a beautiful blood red when cut & milled, but turns gray as it dries.
jlpoole
New Member
It's the bark. The Siberian Elm has the thick pine-link bark, American Elm's is less thick, and the Chinese Elm has thin light colored bark which looks like Sycamore from a distance.
mikeb1079
ArboristSite Operative
i'm always curious when someone posts a casual response to a 4 year old thread. are they just randomly reading old posts? not that it's necessarily a bad thing, i just find it odd.
jlpoole
New Member
i'm always curious when someone posts a casual response to a 4 year old thread. are they just randomly reading old posts? not that it's necessarily a bad thing, i just find it odd.
Well, I have milled several elms and Siberian Elm and I know Chinese Elm and the posting to this topic did not seem definitive, so i thought I'd contribute my experience to help someone distinguish the two. Adding to the knowledge base.
BlueRider
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Sorry to say but you will likely be disapointed. Siberian undoubtably has the most stricking figure and color of the elms I have worked with. Chinese elm will have some subtle pink tones once dry but those are transient and the wood will turn to a medium tan/brown. This is not to say that its not worth milling or using in furniture. It is one of my favorite woods, and I have over 100 slabs of claro wlanut stacked outside my shop.
be sure to have some help on hand it is a LOT heavier than siberian elm.
