Coal Ash, Soil Loss, Sap, Bristlecone Pines. April 5, 2019, Part 1 Listen Download Embed Share Share this on Facebook (Opens in a new window) Share this on Twitter (Opens in a new window) Share this via Email Collecting maple sap in Ohio. ( Chiot's Run/flickr/CC BY-NC 2.0 ) Hosted by Ira Flatow Produced by Science Friday and WNYC Studios