Re: Ortstein vs. Placic Horizons

I'm attaching a couple of papers on placic and ortstein horizons that were sent to me by Dr. Craig Ditzler which discuss the qualities and properties of these materials as well as how they differ. The paper by Brockheim, (SSSAJ, 2011) reviews the occurrences of placic and ortstein horizons in the USA. The paper by Jien, et al (19th WCSS, 2010) discusses the morphology and chemical characteristics of these horizons in subtropical subalpine forests. Both provide a wealth of information on the properties and qualities of these horizons that we should consider as we work to describe them in soil survey and soil classification. I think there is great deal that can be done to better distinguish these pedogenic features in Soil Taxonomy. I hope we hear from those participating in this Forum who have experience with placic and ortstein horizons and can provide clarity to the issue.