For about four years, I have received requests from anglers to look at algae blooms in Putah Creek, especially at Fishing Access No. 5. All of those surveys have been NEGATIVE for Didymo. The identification of Didymo (Didymosphenia geminata) requires a microscopic examination to look at the diatom cells. As of today (9/6/10) all algae surveys in Putah Creek have been negative for the invasive algae called “Rock Snot” or Didymo. Please halp protect Putah Creek and other waterways by cleaning your boots and all equipment.