C14 has a half life of 5730 years and is only good to date objects to 50,000 years or so.
That led me to this non-technical article, and from there followed a link to the asa3article. I think the news item on their front page refers to a much older event. Thanks for your responses and the links to various sources. I am working my way through Kirk Bertsche's 9 page essay on the subject. I'm a complete non-expert in this field of radiometric dating, but it strikes me reading this how contamination by modern carbon introduced during sample preparation seems to be a severe issue.
Related Topics: More Lessons for Biology Math Worksheets A collection of videos and experiments that are suitable for Biology. Andersen explains how carbon-14 dating can be used to date ancient material.
The half-life of radioactive carbon into nitrogen is also discussed.
Another thing I've heard from creationists is that fossils made by soaking samples in tar pits appear to be extremely old.