Traveling with several seasoned staves in the back of the truck for several days  should I worry about them getting wet or try to wrap in a tarp? 

Tarp them.

What kind of wood is it?  I think I'd try to protect it from rain but just traveling with it shouldn't be a problem. Be sure the ends are sealed well and any exposed back.

The wood is osage this was cut the ends sealed in 1996. I agree with the tarp, hate to get to Twin Oaks with wet wood but I don't think that they would gain much if any moisture and I don't want to learn the hard way.

Better safe than sorry.