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This is possibly a silly question, but...
Does anyone know whether there is any difference in timber structure between the juvenile and adult forms?
ie. Once the tap root strikes water and the tree starts to branch out, are subsequent rings visibly different? When dating a tree by counting rings, can one point at a section and definitively say "this is when it matured?"
Umm. Why would it have "juvinile" and "adult " forms? Does it have a leaf differance? Its not like a butterfly or something. Do you mean when it starts having heartwood AND sap wood?
I do have a lump in the stash. Now I'm curious I'll have to go and look. But I don't think my bit includes the very centre of the tree. It has sap wood though.
Hmm. Yes it does have the centre as well. Seems to have an area about as big as a 1 cent piece that is all one tone. I'm not counting the rings though. I already have a head ache. :P The whole "log" must have only been 4 inches across max.
The juvenile form looks rather like a skinny fir tree. Just a hairy trunk... and all it's effort goes into putting down the tap root. Where I saw them, the water table averaged 60m down! Once the tap root reaches the water table, then the tree forms branches and starts to look more like a silky oak.
There's a pic on wikipedia that shows both forms.
Naturally, I'm wondering how it'd turn... :D
At a guess I'd say that your piece is from either a small juvenile or a branch, TL, as the adult ones I saw were around 8" to a foot in diameter.
Sorry Skew, can't help with differences. I have some of the adult tree, but not the juvenile, never had much interest in turning what effectively are branches :rolleyes:.
What sparked the interest in the first place? You don't exactly live in the desert country, so have you already got some?
Spent the last week out Uluru way and was tempted with work out there, pushing camels around, but the choice of local turning materials to feed the habit are a bit... limited... to say the least.Quote:
Originally Posted by dai sensei
Not to mention protected in some way or another :rolleyes:Quote:
Originally Posted by Skew ChiDAMN!!
Just read this. Here is some general information on Australian native trees & woods.
Many Australian native trees (unlike the hardwoods ie the flowering trees, not the pollen-bearing softwoods) often do not produce growth rings annually. This is because their growth is not determined by seasons, eg winter leaf loss when growth stops or with spring leaf growth and start-up, like say the oaks, elms etc of Nthn hemisphere trees.
Our flowering plants ie our hardwoods like the eucalypts, acacias etc grow when it rains! Same with the ancient casuarinas which though not flowering (insect pollinated) these plants also do no loose their foliage in cold seasons. They are like the true pines in some ways but very different in other ways eg the medullary rays in their woods makes them appear more like the oaks (Quercus sp.)
An Australian tree can put on new growth (show growth spurts & rings) eg as a result of good rain or a good growing season. Thats the norm.
So think of Australia's generally moderate climate and rainfall patterns whne thinking of tree growth and wood rings. There are exceptions eg the native cedars.
Red & white cedar, some of few native species which are deciduous, do have bold annual growth rings and this is also why their woods look good when backsawn.
Droughts produce little or slow growth and most dryland / desert plants grow (ie make wood) SLOWLY. This often results is hard dense and often dark timbers.
Hope this is helpful. I have just updated this ramble with more information.,
Euge
Where can one get Allocasuarina decaisneana timber? (Legally!) I'd love to try some, having admired the trees around Alice Springs (both juvenile and mature forms).
Hmm, very old thread, butQuote:
Originally Posted by ROWLAD
There is some around. Try old woodturners or wood collector's piles. I have some, but not much, and not willing to sell
You should also join the International Wood Collectors Society if interested in the rarer species
Thanks, Neil
I visited central Australia recently and was fascinated by the forests of Desert Oak and the remarkable difference between juvenile and mature forms of the tree. The mature ones seem consistently symmetrical and I thought that there was clearly a possibility of timber being derived from the fairly stout trunks on many specimens, so I simply searched on 'Allocasuarine decaisneana' and came across this (admittedly elderly) thread.
I actually got my small log from a IWCS meeting auction. I'm heading to WA in a few weeks, and going via Alice Springs, so no doubt see a few of these plus many other species along the way.