Eucalypts Fire Survival Secret

Ekka · 18th February 2008, 03:46 AM

Quote:

THE EUCALYPT'S SURVIVAL SECRET

The eucalypt trees burnt in Australia's recent bushfires are already sprouting again ? and one botanist has worked out how they do it.

Dr Geoff Burrows from the Department of Agriculture at Charles Sturt University has discovered that eucalypts regrow in a way unlike any other tree in the world.

His findings have overturned long held beliefs about eucalypts, which had always been assumed to ?bud? like all Northern Hemisphere trees.

"People just assumed that because all trees in the Northern Hemisphere are the same, eucalypts will be too," explained Dr Burrows, who has spent the past five years on the research.

Northern Hemisphere trees like oak and willow have buds near the bark surface. They can resprout from the ground if they are chopped down but, unlike eucalypts, are unable to regenerate if they are burnt in a fire, because the buds are killed.

Dr Burrows has found that the lumps on the bark of eucalypts are not actual buds but are connected to bud-forming tissue located beneath the bark. The connection is via tubes called "bud traces" which run from the centre of the tree through the wood to the bark.

"If you follow one of the lumps back in along the tube, when you get near to the bark or the inner wood, you find cells that will make buds if the tree gets the signal," he said.

While all trees have bud traces, including those in the Northern Hemisphere, eucalypts bud traces are the only ones that don't end in an actual bud.

The placement of the bud-forming tissue in the eucalypt bud trace means it can lose 2 cm of bark in a fire and still be able to regenerate.

"As long as the whole tree doesn?t get killed, there will still be some of this bud-forming tissue somewhere in what?s left of the bark," explained Dr Burrows.

The bud-forming tissue forms buds in response to signals such as a lack of photosynthesis, which happens when green leaves are burnt off a tree.

Unlike other trees, eucalypts are not restricted to sprouting from the ground. They can resprout from any point on the tree even five to 10 metres up in full sunshine.

"It gives them a real head-start on other plants that might be trying to restart after a fire," said Dr Burrows.

He said the difficult task of cutting thin sections of eucalypt involved the use of a new technique in which liquid plastic was poured into the wood and then set before cutting.

"It?s nice that eucalypts really are different," said Dr Burrows. "Because of the environmental pressures they have been under they have come up with something that has enabled them to get a competitive advantage on other plants."

Dr Burrows' research was published in the January 2002 issue of the journal New Phytologist.

Source of the given news and the copyrights belong to a ABC Online News
Publishing date: February 20, 2002

TreeDimensional · 18th February 2008, 12:58 PM

While reading the post all I could think was "This Buds for you". It makes you wonder how many more secrets the trees have in store for us.

You would think that in todays global climate, that more research would be going on. I recall an article published in Arborist News a couple of years ago, that stated that it was the first time ever the the genetic sequence for a black poplar had been mapped. For all the old home remedies and the pharmaceutical research that use tree products, we would be made more aware of the importance of our green giants.

treeseer · 20th February 2008, 08:08 PM

While all trees have bud traces, including those in the Northern Hemisphere, eucalypts bud traces are the only ones that don't end in an actual bud."

I'm not sure about this.

Still, fascinating study. It may explain why topping eucs may not result in a failed tree.

The big question is: are all traces created equal? Do any end in a dormant bud, and how many, and where?

Have they learned anything new in the last 6 years?

arbdog · 13th April 2008, 04:11 AM

What happened to el grando (or the name was somthing like that)! It was accidently burnt in a controlled fire! did that regenerate?

Ekka · 14th April 2008, 04:41 AM

El Grande died.

The Wilderness Society - Conclusions on 'El Grande' (Eucalyptus regnans)

Quote:

# The dead and hollow centre of the tree extended up to at least 60 (65?) metres from ground level.
# Further openings in the trunk were evident at approximately 20 metres.
# The fire had burnt to the tree and then had been drawing into the ground-level openings.
# The dry rot and wood inside the trunk had ignited and the configuration of draught holes at the base with outlet holes further up had acted like a furnace and chimney.
# The temperatures generated within the tree core mush have been extremely high, virtually "cooking" the tree from the inside-out!
# The external furnacing had extended to 60-65 metres where the flames appear to have exited from some hollow branches of this level. N.B. The charring is visible!

18th February 2008, 12:58 PM	#2 (permalink)
TreeDimensional Afterburner is shakin' Join Date: Feb 2007 Location: Canada Posts: 381	Re: Eucalypts Fire Survival Secret While reading the post all I could think was "This Buds for you". It makes you wonder how many more secrets the trees have in store for us. You would think that in todays global climate, that more research would be going on. I recall an article published in Arborist News a couple of years ago, that stated that it was the first time ever the the genetic sequence for a black poplar had been mapped. For all the old home remedies and the pharmaceutical research that use tree products, we would be made more aware of the importance of our green giants. __________________ West Central Saskatchewan ISA Certified Arborist

20th February 2008, 08:08 PM	#3 (permalink)
treeseer Afterburner is shakin' Join Date: Jul 2007 Location: SE USA Posts: 410	Re: Eucalypts Fire Survival Secret While all trees have bud traces, including those in the Northern Hemisphere, eucalypts bud traces are the only ones that don't end in an actual bud." I'm not sure about this. Still, fascinating study. It may explain why topping eucs may not result in a failed tree. The big question is: are all traces created equal? Do any end in a dormant bud, and how many, and where? Have they learned anything new in the last 6 years? __________________ Guy Meilleur \| Forensic Arborist \| Better Tree Care

13th April 2008, 04:11 AM	#4 (permalink)
arbdog Cruisin' Join Date: Aug 2007 Location: england Posts: 97	Re: Eucalypts Fire Survival Secret What happened to el grando (or the name was somthing like that)! It was accidently burnt in a controlled fire! did that regenerate?

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