Dr. David Montgomery has been so prolific, that for several years I actually thought he was two people:First, Dr. D. Montgomery is a well known geomorphologist from the University of Washington (and a 2008 MacArthur Fellow) whose name is on much of the seminal, high-gradient channel transport and classification literature. And then there David Montgomery,  the narrative non-fiction author from Seattle who wrote books like Dirt, The Rocks Don’t Lie, and The Hidden Half of Nature.It actually took me an embarrassing amount of time to realize that this was the same person.So the first time I sat down to scribble a list of guests I’d like to invite on a yet to be named river process podcast, Dr. David Montgomery was on that first list…because who wouldn’t want to talk to both those people...especially at the same time.In this conversation David and I moved between the spatial and temporal scales his work spans,  discussing the deep sediment history from his books and his classical technical work. We cover the role of sediment in the rise and fall of ancient near-eastern civilizations, high-gradient river classification, a surprising story about the long temporal tail of wood impacts in natural river systems, incipient motion at the grain scale, and, somehow, a range of other topics. And, I found out that there is, actually, a third David Montgomery…guitar and vocals for the Seattle band Big Dirt, so most of the music you’ll hear (after the opening theme) is from their new album.  You can find David's books that we talked about here:Dirt - https://a.co/d/eaE9P3YThe King of Fish - https://a.co/d/2wArLH1The Hidden Half of Nature - https://a.co/d/eaE9P3YAnd you can access music from Big Dirt here:https://www.reverbnation.com/bigdirtmusichttps://www.bandmix.com/bigdirt/This series was funded by the Regional Sediment Management (RSM) program.Stanford Gibson (HEC Sediment Specialist) hosts.Mike Loretto edited the episode and wrote and performed the music.Video shorts and other bonus content are available at the podcast website (which was temporarily down but is back up now):https://www.hec.usace.army.mil/confluence/rasdocs/rastraining/latest/the-rsm-river-mechanics-podcast...but most of the supplementary videos are available on the HEC Sediment YouTube channel:https://www.youtube.com/user/stanfordgibson