You'll never mindlessly pop a cork out of a bottle of wine after hearing this podcast.  Greg Hirson, who is the Technical Services Manager for Cork Supply USA, takes me in depth through the meticulous processing from tree bark to wine stopper.  Its Greg's job to educate wineries on best practices for selecting appropriate closures and implementing sound bottling practices.  He describes how it is not until the third harvest of tree, after almost 60 years of growth, that the bark is of a quality suitable for wine bottles.  Subsequent bark harvests come every 9-11 years and a tree can give 10-15 harvests over the span of its production life.  
Our conversation begins with a background and history of how wines have been ruined by TCA (tri-chloroanisole) - "corked" wines.  The entire cork industry has taken great efforts to identify the sources of TCA and then to develop processing procedures to reduce its incidence.  These efforts have spurned great leaps forward in delivering better quality corks to wineries worldwide in the past 20 years.  Greg mentions the Cork Quality Council, which is an industry non-profit group that was created to promote education regarding cork stoppers.  The final part of our conversation covers some of the best techniques and procedures for bottling wines with both corks or capsules.