The general rule when selecting the type of wood to use for food smoking is that fruit and nut trees will produce a sweeter/milder smoke. These woods are best with white to pink meats. Hardwoods will create a stronger smoke often best suited to red meats. 

Woods like iron bark and gums may create a very strong smoke flavour and need to be used lightly when smoking goods. The main thing to consider is that you do not over do smoking. When smoking meats it is definately a case of less is more as smoke is to enhance flavour not dominate it.

If you want to slow down the burn rate just wrap your chips in aluminium foil with a few holes pierced in the foil and place in smoker box. Wood chips may also be dampened lightly with water if desired.