It doesn't appear to be fundamentally weaker for many applications. If it's yields are 3-4x times what "SPF" is, then maybe use slightly larger boards in support roles?
I'm not associated with worldtree.eco, and obviously they are advertising a product, but I can't really find any more discussion on the pro/cons of empress tree wood production.
The invasiveness problem I heard was specific to a particular species of empress, there are empress species that don't spread so aggressively.
You're missing the point: most houses are built without an engineer ($$$) and are only allowed because they follow narrow guidelines about what is allowed. Lumber must be graded SPF. You couldn't substitute oak (stronger) if you wanted to without custom engineering. So for nearly every builder it would cost more to use that lumber than SPF until someone gets it codified into the building code. And, like generic drugs, there's little financial incentive to make that fight with the regulators. So we sit in a local minima forever.
"there's little financial incentive to make that fight with the regulators"
Global warming will be the incentive in this case. If Empress tree lumber is that much better for carbon sequestration, and from what I've read it is a fantastic sink and converting sequestered carbon in trees into lumber in construction is a decent long-term strategy in this case.
Really my only interest in pushing empress tree lumber here is the carbon sequestration. I'm not some empress tree farmer or some other scam. The other advantage is that empress trees are pretty hardy from a soil/arable land standpoint, leading to more opportunities to sequester carbon in areas that don't easily forest over like, maybe, Texas badlands.
The other angle is that rapidly replenishing lumber sources prevent old growth forest from being destroyed, which ties into biodiversity and habitat destruction.
