Monday answer
John was on it. Willow is especially good for bending green for rustic furniture. Still, the ones identified by Schleining are ash, oak, beech and hickory. Accordingly and surprisingly it makes almost no difference if the wood (say 1 inch square) is horizontal, vertical or rift sawn when steam bending in a 90 degree bend or less. However, if a grain runs off the blank it is better left unbent. As to temperature, the ideal temperature is 200 degrees Fahrenheit. And since the box is vented the max temp inside cannot exceed 212 degrees as the steam will escape and condense without any pressure. The idea is not to create a bomb, just bend wood. Finally, be prepared for a wait. As to time, the ideal is one hour of steam for each inch of thickness at 200 degrees. Don't forget a strong jig and a compression strap for best and repeatable results.