White Wax Wood 3 sectional staffs are much better than hardwoods. Wax Wood is lighter but tougher. Will not splinter like other hardwoods.
Ash and Hickory would be better. Take a beating. they make baseball bats from those woods.
Just noticed the question about Red Oak and such.
This is good advice. American Red Oak is pretty prone to splitting, as is white oak, though moderately less so. Japanese Oak is tighter grained and better about this, so some high quality training weapons will be made of it, but you won't find those in the $30 or $40 price range.
Hickory, Ash, and a whole slew of other hardwoods are perfectly good options as well.
More important than the species of wood, however, is the orientation of the grain in the piece and the distribution of weight. Low quality training weapons will generally be haphazard about grain direction, and will be very tip heavy near the point. Both of these qualities contribute to failure more than anything else. Even Hickory, if the grain is wavy or not oriented well, will be prone to splitting.
I've made numerous training weapons out of everything from Hickory, Maple, to Red Oak, and even Poplar. And, believe it or not, the Poplar has held up fantastically along with everything else - dents everywhere, of course, but I'd actually defy anyone to break them during normal training. They hold up to their intended purpose of very robust, light-weight training implements.
I also taper the blades distally (in thickness), which contributes both to their balance and lively feel (giving them the feel of a blade, rather than a club in the hand), reduces wrist strain for the practitioner, and furthermore makes them less prone to failure when clashing with an opposing weapon because less of the mass is out past the tip.
Quality wooden training weapons like this will almost invariably be hand made, are somewhat difficult to come by, and will be in the $80+ range, but are worth it, in my opinion. Of course, you can also make your own, but unless you're already an experienced woodworker and have a variety of hand tools, it would be far cheaper/quicker to buy a few, though not nearly as fun as making them