Redbud would be what I would call a difficult wood. It can have some excellent figuring, but it is a very soft wood that splits easilly and has a very high shrinkage when it dries. Coat the wet blanks with AnchorSeal or wax, and still be prepared to lose at least half of the blanks when drying them. Don't coat it, and lose all of them.
Magnolia can also be a good wood for a pen if the grain is right, but it can also be a very plain light yellow wood when it isn't. And it can turn a bluish color. The problem is that there is no way to know until after the tree has been cut down. Either way, it is easy to turn and finish. It has a large figuring that would look better on something larger than a pen. It is one of my favorite woods for salad bowls and large platters
The modified ElGrande pen in the photo will give you an idea what colors you will find in Magnolia. I don't have a photo of a Redbud pen.
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