The Australian Bull Oak tests out as the most difficult to penetrate by at least one measure.
Common trade names: buloke, bull-oak
Genus: Allocasuarina luehmannii
Janka Hardness (pounds-force): 5060
Description: Possibly there exist limitations to what a woodworker will endure. I’ve been unable to locate any information about the use of this lumber as a lumber, but I’ve found that it’s vital to the continuing survival of a southeastern subspecies of the Austrialian Red-tailed Black Cockatoo for both food and lodging.
Location: Victoria, Queensland, New South Wales in Australia
Common Aliases: Australian buloke, Australian bull-oak
Performance: If you can get your hands on some of this, please let me know how it turns out for you. I believe it would be interesting to hear at least one opinion except that it’s the hardest wood that’s been tested with the Janka scale. There is mention from Australian government issues alluding to its strong performance as a fuel wood. It looks like it should be able to grow about anywhere, and it is unclear whether this wood is useful at all to the professional or hobbyist woodman.
Acclimation: It looks as though one would have to travel to Australia, and possibly purchase this wood on the black market. I have seen no place where it is being sold in the United States, and I don’t know how Australian jails might differ from American ones, should its trade be illegal. Again, your input could be helpful in this identification project.
Common Uses: Nesting and feeding of the Australian Red-tailed Black Cockatoo.
From: florabank
Common Name(s): Allocasuarina luehmanni
Scientific Name: Allocasuarina luehmanni
Distribution: Queensland, Western New South Wales, Northwestern Victoria
Tree Size: 30-60 ft (10-20 m) tall, 2-3 ft (.6-.9 m) trunk diameter
Average Dried Weight: N/A
Basic Specific Gravity: N/A
Hardness: 5,060 lbs.f.
Rupture Strength: N/A
Elastic Strength: N/A
Crushing Strength: N/A
Shrinkage: N/A