Milestones in soil morphology and pedogenesis

The progress of pedology has been remarkable when we consider that soils were noted as discrete from geological materials less than 100 years ago. Thus, much of the time for advancement of pedology research has occurred within the 90-year longevity of Soil Science celebrated with this issue. Many of the major advances are related not to just one article, but usually, a group of articles on a particular subject. Certainly, there have been leaders in the field and these are noted in the articles reprinted here and references. The nine milestones selected a range from recognizing soils as natural bodies to the application of laboratory methods such as scanning electron microscope and energy dispersive X-ray.