How to ID the Eucalyptus worth milling?

[KiwiBro]

From what I've heard, there's only a few types here in New Zealand worth milling. The rest are unstable, twist or crack too much during drying, etc. There's a bunch of big, straight Eucs for me to drop this Summer but I'm not sure firstly what types are lumber and what are firewood trees, and secondly how to ID them properly. It would be a shame for these big, straight trees to become firewood if they have a higher station. Especial as most of them are clear of branches for the first 15 metres or more.

Can anyone help please or point me in the right direction? Thanks in advance.

 

[TraditionalTool]

The Eucalyptus we have on the west coast of the U.S. is Tasmanian Blue. Yes, I heard it is tough to keep from checking.

I have some but haven't milled it up yet. They make flooring out of it in the U.S., as it is hard stuff.

There are other Eucalytus and Sweetgum down under, maybe BobL can help you out with more info.

 

[BobL]

From what I've heard, there's only a few types here in New Zealand worth milling. The rest are unstable, twist or crack too much during drying, etc. There's a bunch of big, straight Eucs for me to drop this Summer but I'm not sure firstly what types are lumber and what are firewood trees, and secondly how to ID them properly. It would be a shame for these big, straight trees to become firewood if they have a higher station. Especial as most of them are clear of branches for the first 15 metres or more.

Can anyone help please or point me in the right direction? Thanks in advance.

There are at least 800 species (and more are still being discovered) of Eucalyptus but fortunately only about 100 species grow into millable logs. IDing with just a written description is just about impossible and not that accurate using photos. Here in Oz arborists often take short courses on identification since it involves detailed knowledge of the leaves, flowers, and fruits(or nuts) of the tress. The most accurate way to ID them is by photographing the polished end grain with a microscope.

If you want to do things for yourself the web has some info but only on the most common sepcies
eg Forest Products Commission: Plantations: Species information: Plantations: Tasmanian blue gum
Forest Products Commission: Plantations: Species information: Plantations: Spotted gum
But even here you will see the info and photos provide are limited.

I have a 730 page book here published by the Commonwealth Scientific, Industrial and Research Organization called Forest Trees of Australia that has details of the most common Eucalypts. If you post some pictures of the tree itself, and come close ups of the bark, leaves (both mature and new) and is they have any flowers or nuts and I will give it a go. If you can it's better if you remove the leaves and flowers/nuts from the tree and put them on a neutral plain background before photographing them

 

[BobL]

The Eucalyptus we have on the west coast of the U.S. is Tasmanian Blue.

San Diego also has heaps of twisted and stunted Spotted Gum or Spotties as we call them.
It's a pity because this makes pretty nice timber when grown in the right conditions.
In Australia Spotties are often (mistakenly) planted in domestic gardens where they get a lot of water and years later they grow so big with a very wide and start dropping big branches and it costs the home owner thousands of $$$ to have them taken down.

 

[KiwiBro]

Thanks Guys. I think we've E.Globulus and E.Saligna, but of those that are not blue gums, I'm not sure. Many of the really impressive ones didn't have bark as such and were almost shiny if that makes sense. Ill get some photos when I'm next out there.

 

[BobL]

Thanks Guys. I think we've E.Globulus and E.Saligna, but of those that are not blue gums, I'm not sure. Many of the really impressive ones didn't have bark as such and were almost shiny if that makes sense. Ill get some photos when I'm next out there.

Spotted Gum looks smooth silvery shiny and looks like it has no bark except around the base of the trunk.
Technically it's not even Eucalypt but a Bloodwood (Corymbia maculata)