Douglas-fir [Pseudotsuga menziesii (Mirbel) Franco] bark (DFB), sphagnum peat moss, and pumice are the most common substrate components used in the Oregon nursery industry. Despite the widespread use of these three co ...

The study area lies north-northeast of Crater Lake National Park and is covered by 2 to 3 m of pumice deposited during the climactic eruption of Mount Mazama approximately 7700 years before present. The pumice deposit ho ...

The Bend pumice and Tumalo tuff are products of a plinian eruption which occurred sometime between 0.89 and 2.6 m.y. The Bend pumice is a poorly consolidated, air-fall vitric lapilli tuff, which overlies a zone of rework ...