Marvin, all woods that have been kiln dried are sterilized at the end of the drying cycle.
Although it is possible to safely air dry many species, some woods - such as magnolia - are a little more susceptible to hosting powder post beetles or other unwanted pests, and it's best to err on the side of caution when obtaining air-dried versions of these woods.
Many woodworkers will purchase air dried wood and then sterilize it themselves in their shop. FWW had an article about a year ago about how to build a simple home sterilization chamber.