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The article announces the passing of J. Ronald Eyton, a faculty colleague, who died unexpectedly in March 2022. Eyton had a successful career in academic cartography, holding various academic appointments and supervising numerous doctoral and master's students. He was known for his expertise in cartography visualization and remote sensing, and he published over 50 papers and made over 30 professional presentations. Eyton's retirement did not slow him down, as he continued to travel and explore with his spouse. The article encourages readers to contribute to the ASPRS International Educational Literature Award in Eyton's memory. [Extracted from the article]

Abstract: Trees affected by mass movements record the evidence of geomorphic disturbance in the growth-ring series, and thereby provide a precise geochronological tool for the reconstruction of past activity of mass movement. The identification of past activity of processes was typically based on the presence of growth anomalies in affected trees and focused on the presence of scars, tilted or buried trunks, as well as on apex decapitation. For the analyses and interpretation of disturbances in tree-ring records, in contrast, clear guidelines have not been established, with largely differing or no thresholds used to distinguish signal from noise. At the same time, processes with a large spatial footprint (e.g., snow avalanches, landslides, or floods) will likely leave growth anomalies in a large number of trees, whereas a falling rock would only cause scars in one or a few trees along its trajectory. Based on the above considerations, we examine issues relating to the interpretation and dendrogeomorphic dating of mass movements. Particular attention is drawn to sampling in terms of sample distribution across a study site, the actual selection of trees as well as to sample size (i.e., number of trees sampled). Based on case studies from snow avalanche, debris flow, and landslide sites, we demonstrate that thresholds can indeed improve dating quality and, at the same time, minimize noise in time series. We also conclude that different thresholds need to be used for different processes and different periods of the reconstruction, especially for the early stages of the reconstruction when the number of potentially responding trees will be much smaller. This paper seeks to set standards for dendrogeomorphic fieldwork, analysis, and interpretation for different processes of mass movements. [Copyright &y& Elsevier]

Abstract: Fieldwork has a long and honored tradition in mountain geomorphology, and justifiably so. Many features and processes present in mountains occur at fine to very fine spatial scales that simply do not lend themselves well to analyses via remote methods. The nature of the sampling of data in mountain environments also constrains the use of computational techniques, such as GIS, in favor of on-site data collection. In addition, when one is present in the field in mountains, the dynamic nature of the landscape often provides unexpected rewards that could not be planned for in a campaign of remote analysis. These aspects of scale, sampling, and serendipity make on-site fieldwork still the preferred method for geomorphological research in mountain environments. Several examples of features occurring at fine spatial scale that could only be effectively examined in the field are presented in this paper, as well as examples of data sampling occurring at fine scale. I also illustrate several instances where being on-site, at a specific unexpected moment, in the dynamic mountain environment provided scientific insight that could only be obtained through the serendipity of being there. Why continue to conduct geomorphological fieldwork in mountains? “Because the mountains are there”! [Copyright &y& Elsevier]

Abstract: Many animals in the mountains of the western U.S.A. and elsewhere are geomorphically active. The spatial pattern and intensity of these impacts, associated with activities such as digging for food, burrowing for shelter, and damming of streams, may change as a result of climate change. Food sources utilized will be affected by processes such as meadow infilling with trees, upward advancement of trees, and changes in intensity of other geomorphic processes such as avalanching and glacial action and associated meltwater. Examples are presented here that illustrate the importance of accurate habitat mapping to be able to assess the impact of climate change on geomorphically active animals, as well as the importance of knowledge of food sources of these animals. As climate change impacts food sources and habitats, some geomorphically active animals may become much more limited in the geographic range and intensity of their influence, and some may disappear altogether if the habitat disappears. [Copyright &y& Elsevier]

ABSTRACT Many beaver ponds in the Rocky Mountains, that have been described in the literature, are in-channel ponds that are relatively small and short-lived. This paper describes floodplain beaver ponds on low-gradient deltas in glacial finger lakes in Glacier National Park, Montana. These ponds are distinctly larger, probably fed by hyporheic flow, and stable and long-lived. Ponds examined were, with one exception, 44 years old. Glacial discharge is present in each valley where beaver ponds occupy low-gradient deltas, and this discharge likely sustains pond water level over the course of the summer. As glaciers recede and disappear, deltaic beaver ponds dependent on hyporheic flow may be negatively affected. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

For over 100 years, mountain treelines have been the subject of varied research endeavors and remain a strong area of investigation. The purpose of this paper is to examine aspects of the epistemology of mountain treeline research-that is, to investigate how knowledge on treelines has been acquired and the changes in knowledge acquisition over time, through a review of fundamental questions and approaches. The questions treeline researchers have raised and continue to raise have undoubtedly directed the current state of knowledge. A continuing, fundamental emphasis has centered on seeking the general cause of mountain treelines, thus seeking an answer to the question, "What causes treeline?" with a primary emphasis on searching for ecophysiological mechanisms of low-temperature limitation for tree growth and regeneration. However, treeline research today also includes a rich literature that seeks local, landscape-scale causes of treelines and reasons why treelines vary so widely in three-dimensional patterns from one location to the next, and this approach and some of its consequences are elaborated here. In recent years, both lines of research have been motivated greatly by global climate change. Given the current state of knowledge, we propose that future research directions focused on a spatial approach should specifically address cross-scale hypotheses using statistics and simulations designed for nested hierarchies; these analyses will benefit from geographic extension of treeline research. [ABSTRACT FROM AUTHOR]

To mitigate the impact of direct human activity on treeline pattern and process, much alpine treeline research in the western USA has been conducted in nationally protected areas. The use of treeline as a proxy for climate change has been assessed in parks throughout the west but often at the expense of geology or geomorphology as controls of treeline variation. The dissimilar geology and geomorphic processes of the western national parks suggest that treeline may respond differently between national parks when subjected to disturbance. Therefore, predicted vegetation response to disturbance across the western USA may provide a limited assessment of change beyond fine-scale analysis due to data collection from a limited number of national parks containing alpine treeline. We performed a content analysis on previous research that examined alpine treeline in national parks and classified each treeline study as anthropogenic, orographic/edaphic, or climatic according to the primary factor attributed to treeline control. Results indicated that the three types of treeline are not uniformly studied. Climatic treeline is most commonly studied whereas anthropogenic and orographic/edaphic studies are often lacking. Furthermore, several western national parks are entirely devoid of anthropogenic and orographic treeline research. Similar findings exist for treeline studies in protected places worldwide. More research in protected places is required to broaden our understanding of multiple treeline processes across both regional and worldwide extents. [ABSTRACT FROM AUTHOR]