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Caveman
18th March 2007, 05:27 PM
G'day,
What causes the formation of burls - is it from damage (insect/mechanical), fungi, bacteria???

Ever since catching the turning virus I've always been on the look out for burls but have yet to come across any. We have loads of Eucalypts in this part of the world from since the early settlers brought them in in the early 19th century.
I always keep my eyes open and have yet to see any - not just on Eucalypts but on any tree.

Anyway the search continues, but would be interested to know what brings them about - maybe we don't have the right 'ingredients' over here.

dazzler
18th March 2007, 06:15 PM
Aliens, fungal or insect attack.

Especially if there has been damage to that part of the tree.

Often caused by drunken aliens shooten lasers.

You need some aliens.

Skew ChiDAMN!!
18th March 2007, 06:28 PM
Think of 'em as a form of skin cancer for trees.

What causes skin cancer in humans? Well... we've got a range of known causes, a range of suspects and, I'd imagine, there are causes we don't know about yet. This has been the subject of many years of study.

AFAIK, far less effort has gone into the matter of burls. We have many suspects: stress, bacteria, insects, fungii and, yes, even aliens playing with our minds. :rolleyes: But no-one really knows although everyone has their opinions.

Personally I suspect that a lot of 'em are just petrified echidnas, chased one too many times up a tree... Do you have echidnas in your part of the world? No? See? I rest my case. :p

Caveman
18th March 2007, 06:31 PM
Aliens,

Often caused by drunken aliens shooten lasers.

You need some aliens.

:oo: :oo: :oo:
I'm seen as one of them - at least that's what is says on my ID card!!! Not being of the indigenous skin colour, this is what were labelled as!
Now where did I put that laser..............

Seriously though - thanks - that's what I thought - we obviously don't have the right insect/fungi - still won't stop me lookin though - never know.

glenn k
18th March 2007, 06:34 PM
there is a bacterium that causes crown gall but this is not the only cause.

Caveman
18th March 2007, 06:35 PM
AFAIK, far less effort has gone into the matter of burls. We have many suspects: stress, bacteria, insects, fungii and, yes, even aliens playing with our minds. :rolleyes: But no-one really knows although everyone has their opinions.

Personally I suspect that a lot of 'em are just petrified echidnas, chased one too many times up a tree... Do you have echidnas in your part of the world? No? See? I rest my case. :p

:) Thanks Skew - nope, none of them round here that's for sure, but plenty other 'scared' things:D runnin up trees!!! Obviously the trees don't last long enough for the burl to form!

dazzler
18th March 2007, 06:43 PM
the geeks have an idea

http://www.wisegeek.com/what-is-burl-wood.htm


cheers

Caveman
18th March 2007, 11:53 PM
the geeks have an idea

http://www.wisegeek.com/what-is-burl-wood.htm


cheers


Thanks for the link.

ciscokid
19th March 2007, 04:03 AM
As you can see from the responses, nobody knows.

rsser
19th March 2007, 07:47 AM
That shouldn't stop us from opining.

Shedhand
19th March 2007, 09:40 AM
nematoda burlensiata commonly known as the Burly Worm as in "the burly worm catches the bird". and the reason he can do this is that Burly Worms live on steroids found naturally in eucalypts making them big and strong which causes the hump in the tree known as a Burl. True mate. :wink:

Gil Jones
19th March 2007, 12:54 PM
I think that "burl fairies" cause them.

Bleedin Thumb
19th March 2007, 01:21 PM
The trunk of most trees, but especially Euc's are covered by epicormic buds that can sprout to form new branches if conditions are right IE bushfire, physical damage etc.

Sometimes these epicormic buds "misfire" and instead of producing new growth in the form of leaves and stems produce growth in the form of woody tissue. Hence burls...........














I have to admit I just made that all up, but its as good a theory as any.:D

joe greiner
19th March 2007, 01:51 PM
I have to admit I just made that all up, but its as good a theory as any.:D

No you didn't.

http://www.google.com/search?hl=en&ie=ISO-8859-1&q=epicormic+burls

:D

Joe

Shedhand
19th March 2007, 02:05 PM
Seriously though I got this response from my mate at Forestry Tas when someone else asked this or a similar question early last year. Go to the bottom of this post and read emails from the bottom up


To: Steve Rea[
Date: Jan 19 2006 - 8:33pm
Dear Mike

I am not as much an expert in wood anatomy as Tim Wardlaw suggests.
The best descriptions of these phenomena of elliptical defects
(birds-eye, not always caused by dormant buds) and longitudinal waves
(fiddleback) are to be found at
http://www.woodworkforums.com/%3Ca%20href="] http://www.ag.auburn.edu/aaes/communications/bulletins/figureinwood/
http://www.ag.auburn.edu/aaes/communications/bulletins/figureinwood/
and
http://www.woodworkforums.com/%3Ca%20href="] http://www.hobbithouseinc.com/personal/woodpics/_figure.htm
http://www.hobbithouseinc.com/personal/woodpics/_figure.htm

Hope these prove useful. I have not found more detailed explanations
of the origins of these phenomena.

Regards

Steve Read



Steve Read
Chief Scientist
Forest Research & Development
Forestry Tasmania

Tim Wardlaw 13/01/2006 2:11:10 pm

Gents,
I have sent an interim e-mail to Mike Gard (copy below) but would
appreciate it if you could add your repective expertise.
Thanks,
Tim

Afternoon Mike,
Evan forwarded you question on to me to deal with He mentioned
something about being buried under legal documents so I reckon he would
prefer to be talking about wood grain in eucs than what he is currently
doing.

Your question is outside my field of experetise (pathological
problems including wood decay) so I will forward on to two people in FT
who might be able to give you more info - Rod Hill, who co-ordinates
wood sales and has alot of field experience in developing log
specifications; and Steve Read, our Chief Scientist, who before he
became a research manager worked in wood anatomy at Melbourne Uni.

From my limited experience I believe fiddleback and wavy grain generally are
strongly under genetic influence. Birdseye is a concentration of dormant
buds (epicormic buds). It's very common in burls, which in that case is
an age-related genetic abnormality (much like cancers in people).

However, I don't think birdseye is restricted to burls and may occur as
an abnormality in the main trunk but I am not sure of the factors that
would lead to such development.

Hopefully Rod and Steve might have more info.

Evan Rolley 13/01/2006 11:17:13 am

Tim, Please send Mike you considered reply on my behalf..I am up to my
armpits in legal documents ahead of Mondays action. Thankyou, Evan

Mike

G'day Evan
How're you doing?

Just wondering if you can tell me (or point me to someone who can) what
causes fiddle-back and birdseye grain in eucalypt - or any tree for
that matter?

Is it to do with water supply or is it just an inexplicable quirk of nature?

Cheers
Mike Gard

Thanks very much Steve. Just what I was after.

Cheers

Mike

Bleedin Thumb
19th March 2007, 02:07 PM
No you didn't.

http://www.google.com/search?hl=en&ie=ISO-8859-1&q=epicormic+burls

:D

Joe


Bloody hell its so hard to have an original idea these days:D

I'm not sure that the term epicormic burl is the same as what I was expounding on about though.

Maybe they (scientists) do know what causes them, and if is because of misfireing epicormic buds.....I've just amazed myself.:rolleyes:

Shedhand
19th March 2007, 02:13 PM
Bloody hell its so hard to have an original idea these days:D

I'm not sure that the term epicormic burl is the same as what I was expounding on about though.

Maybe they (scientists) do know what causes them, and if is because of misfireing epicormic buds.....I've just amazed myself.:rolleyes:bit like a misfiring hair in a human. it doesn't poke through the skin but still grows and becomes a sebaceous cyst. and when you go to have a number 1 haircut the blade slices the top off and all this gunk pops out with a hard piece of hairy cr@p. a human burl.... :D

RETIRED
19th March 2007, 03:30 PM
All fixed Sheddy.

Skew ChiDAMN!!
19th March 2007, 03:43 PM
All fixed Sheddy.

Is it? :innocent:

rsser
19th March 2007, 05:29 PM
.... gotta love it. The chief scientist of Forestry Tasmania quoting a Ubeaut forum post.

Shedhand
19th March 2007, 05:41 PM
.... gotta love it. The chief scientist of Forestry Tasmania quoting a Ubeaut forum post.Even better is the Head of Forestry Tas (now moved on) jumping to my demands... :D. Seriously, they're a much maligned bunch of all round good blokes and excellent scientists doing a very difficult job. :2tsup:

Shedhand
19th March 2007, 05:44 PM
All fixed Sheddy.Thanks mate. I was only saying to Neil on friday what a brilliant mod you are.. on the ball.. plenty of smarts and charisma. .. he told me he's changed his mind about sackin' yer...:D

Hickory
20th March 2007, 06:56 AM
As you can see from the responses, nobody knows.

I know but I just not going to tell you because then I'd have to kill you :2tsup:

But I have heard for a long time that it is a cancer like cell growth, and I have heard that it is an insect bitewhere an foreign substance was introduced and the self protection kicks in and produces a "Cyst" type growth. Being a living organism, there are all kinds of growth derivitives similar to human & animal warts.

RETIRED
20th March 2007, 08:12 AM
Thanks mate. I was only saying to Neil on friday what a brilliant mod you are.. on the ball.. plenty of smarts and charisma. .. he told me he's changed his mind about sackin' yer...:D
Might ask for a pay rise.:rolleyes: :wink:

Shedhand
20th March 2007, 08:21 AM
Might ask for a pay rise.:rolleyes: :wink:lotsa luck...:no:

Bleedin Thumb
20th March 2007, 08:21 AM
Hickory recons warts, Sheddie recons ingrown hairs... I'll vote hemorrhoids.

Actually I like the cancer theory as well.
A cross section of a burl quite often looks like those pictures of dyed, cross sections of tumors you see in medical journals.

Caveman
22nd April 2008, 05:50 PM
Anyway the search continues, but would be interested to know what brings them about - maybe we don't have the right 'ingredients' over here.

Found some!!!

But how to get away with harvesting them is the challenge.

Is it best to rough turn a 'green' burl for re-turning once dried - or complete the whole thing while still green - or dry the whole burl and turn once dried?

Would probably go down the rough turned route as this is what I do for all my bowls, but just wondering what the SOP is for burls.

rsser
22nd April 2008, 05:56 PM
Midnight flit with chainsaw and balaclava to harvest them Andy ;-}

After that, well, I've found burls pretty stable to turn to finish while green.

That said, I'd still wrap them in plakky when away from the lathe for any time.

May vary acc. to species. What's this one?

petersemple
22nd April 2008, 06:01 PM
I have a quick Q on this one. I have heard some people say you can cut a burl off a tree and it will regrow, and others say cutting it off kills the tree - any definitive answers?

Thanks

Peter

rsser
22nd April 2008, 06:50 PM
Burls are regularly harvested by licensed contractors with no damage to the tree.

Caveman
22nd April 2008, 08:39 PM
Midnight flit with chainsaw and balaclava to harvest them Andy ;-}

Looks that way seems to be the only current option!



What's this one?

Hmm - good question - the most common Eucalypt planted around town is saligna, which is possibly what the ones in the background are, but as for the one with burls on it I've no idea.

Perhaps someone would like to hazard a guess - have attached a couple more pictures?

artme
22nd April 2008, 09:34 PM
Read all the answers (belatedly) and found burley a reasonable cause!:D:D:D
Who cares? Just be thankful for their magnificent existence!

tea lady
23rd April 2008, 12:30 AM
Looks that way seems to be the only current option!




Hmm - good question - the most common Eucalypt planted around town is saligna, which is possibly what the ones in the background are, but as for the one with burls on it I've no idea.

Perhaps someone would like to hazard a guess - have attached a couple more pictures?

Gee That tree is just burl!!:oo: Wonder if you could clone them.(Burl trees.)

Bleedin Thumb
23rd April 2008, 10:29 AM
I would guess that it could be a Euc. sideroxylon...the one behind it a saligna with a maculata possibly behind that.

If it is a sideroxylon its a bit crook....:?

Caveman
24th April 2008, 04:46 PM
I would guess that it could be a Euc. sideroxylon...the one behind it a saligna with a maculata possibly behind that.

If it is a sideroxylon its a bit crook....:?

G'day BT - would say all the ones in the background were saligna despite being a bit spotty, but still not sure about the burly one - doesn't quite look right for an ironbark (even if it's a bit crook).

Does sideroxylon burl often?

Will check for any flowers or something more distinctive next time I'm in town.

Anne Munro
25th April 2008, 12:18 AM
It may be of interest to you to know that burls are found in trees around the world. However in Britain they are called Burrs. In Australia, you will find a lot of burls on mallees.

mobjack68
25th April 2008, 01:06 AM
I am in the Appalachian hardwood forest, mountains of Virginia, USA....we see quite a bit of "Burl" growth on trees. The building that I work in is bordered by a river with quite a bit of growth along the rivers edge. There are a ton of trees with "growths" on the limbs and trunks. Some of these range in size from softball to watermelon. They are too high to be physical damage, leads me to believe it is something that has been introduced, viral/fungal and the trees in the bottom that are affected are Black Locust, Honey Locust, Black Walnut (juglans nigris) two varieties of Cherry, Ash, Hickory, Red Oak (quercus ...something) AND Persimmon....the real question is this....what is the best way to season these guys so they will dry adequately with a minimum of "seasoning problems" (splits/checks/cracks/etc) I have cut some, turned immediately to get close to a shape, bagged and dried slow/cut others sealed both ends with paraffin, cut others and bagged to force slow dry....hate to keep wasting these one of a kind beauties.....HELP!!

Zarguld
25th April 2008, 04:37 AM
I thought that every one new how burls were made my college professor told us that it comes from a bug or foreign object and the plants natural instinct to protect itself just like an oyster does with anything that gets in side of its shell but the catch is that not every time something gets in side the plant that it feels threatened so it does not always react I guess it just depends what gets inside.Not sure how correct it is but that is just what I have been told to be true.:U