People have written me asking for more information about the little osage orange plane in the side bar, so here are some images and measurements in case you would like to make one yourself.
Body: 4.5" long • 2" high • 1.125" wide
Opening: .84375" wide (13.5/15")
Wedge: 2.625" long • .8125" (13/15") wide • 12 degree bevel to fit
Blade: 3.625" long • .8125" wide • .125" thick
45 degree bed • 57 degree shoulder (the portion of the sides that hold the wedge in place) • 52 degree front bed
The plane is one piece of wood, so the most difficult part is chiseling out the wood inside the opening and being careful to ensure that the bed is perfectly flat. Layout your angles on the outside of your workpiece and transfer the angles across the top, down the other side, and on the plane's sole. Then, just keep an eye on your progress to make sure you maintain those angles as you chisel out the opening.
Other woods that make good planes are applewood, maple, bloodwood, cocobolo, and many other dense hardwoods.
Growth ring orientation, according to David Finck, author of Making & Mastering Wood Planes, is unimportant.