I just brewed two beers a few weeks ago using white labs cal ale and a kolsch ale. I made 1500 ml starters with both. The Cal ale got 86% apparent attentuation and the kolch 84%. This is alot higher than listed attenuation for both. I mashed both a little on the low side - 149 for the cal ale and 152 for the kolch - but doesnt this attenuation seems a little much even for the low mash temps. Could other factors be at work? (ie, wild yeasts or otehr contaminants?). I ended up with a 1.008 FG on an IPA and a 1.009 FG on a pale. Much dryer than I was shooting for on both.