Yeah, it can work as firewood for heat if its thoroughly dried (1+ year). You have to split it before it dries.

I guess I should clarify my previous post. Most people in CA don't burn wood for heat. I was specifically referring to burning wood for cooking (aka Santa Maria Style BBQ). For that, oak is superior and eucalyptus is a no-go.

Yes it does need to be dried to burn well. I have split by hand an awful lot of seasoned eucalyptus and it is hard work and takes real skill. It is even worse here in Australia as due to the native pests the wood contains a lot more knots. You get used to taking a good look at a log and deciding if that is worth splitting or not.

You can cook with it, but you need to let the fire die down and cook on the coals only - that is unless you love the taste of cough drops.

On the topic of building with it even young eucalyptus is OK if you let the timber season while strapped so it doesn’t twist and warp. The only problem is that it become like iron and is impossible to nail. When I was a kid we had a huge supply of seasoned eucalyptus that my brother and I used to build all sorts of things. We had to pre-drill all the nail holes before we could use it. If you did this it was a 100x better structural timber than pine.

I have long experience as a teenager splitting yellowbox eucalyptus for firewood - it splits considerably better when seasoned.

Yes as long as it is not knotted.

My favourite was logs that had the core eaten out by termites - now they were nice and easy to split :)

Talking of arthropods did you ever have the fun of chainsawing through a bull ant nest while collecting seasoned logs? They are not happy and do they hurt when they bite.