Eric Peterson

Trinity River Restoration Program

This book celebrates the natural history of the Klamath Mountains of northwest California and southwest Oregon through stories of diversity and resilience over deep time. Shaped by geology, these mountains form an ancient jigsaw puzzle and topographic mosaic dissected by big-shouldered river canyons and sharp ridgelines that create localized clima...

Originally described from a single collection in northern California, Umbilicaria phaea var. coccinea has since been reported from additional sites in California, Oregon and Washington. Although relatively rare in all three states, there is currently no conservation status for U. phaea var. coccinea in California. Developing conservation strategies...

Stenocybe procrastinata (Mycocaliciaceae, Mycocaliciales) is described as new to science. The species occurs with remarkable reliability on Cercocarpus ledifolius in western North America.

Photogrammetry, the use of photography to calculate measurements, includes a suite of algorithms known as Structure from Motion (SfM) that model 3D structure from standard photographic images. While use of SfM for objects or scenes at scales from centimeters to kilometers is common, studies that use macrophotography for small objects or scenes are...

Background/Question/Methods SfM photogrammetry uses computer vision algorithms for representing objects or scenes as 3D data and has become the main method used to derive topographic data from Unmanned Aerial Vehicle (UAV, or “drone”) photography. However, SfM has much broader application. The Trinity River, California, was mined for gold for over...

Structure-from-Motion photogrammetry (SfM) is a suite of image analysis algorithms from computer vision sciences. SfM enables feature detection and matching across multiple images, with triangulation to create three-dimensional (3D) point clouds. It is the primary method used for processing drone photography into 3D data, but can be used with obliq...

Northwestern North America has lately been shown to support a rich assemblage of calicioid lichenized and non-lichenized fungi. Here we describe the non-lichenized fungus Chaenothecopsis aeruginosa (Ascomycota, Mycocaliciales) as new to science. This species is endemic to the U.S. Pacific Northwest and adjacent Canada, where it ranges from Oregon n...

This paper documents the learning of a “community of interest” seeking to maximize Reclamation’s capabilities in a developing field of 3D data acquisition referred to as Structure from Motion (SfM) Photogrammetry. Photogrammetry is the use of two dimensional (2D) images to provide measurement data. Structure-from-motion refers to a set of algorithm...

Publishing of papers in scientific journals has long been the gold standard in science. But how long does a typical paper continue to be of much interest? Citations of most papers drop off within a few years and the papers fade off into history. But DATA...! Ah, there is something that can easily live on! Ecology is discovering that times change, s...

Introduction Sagebrush ecosystems in western North America are being replaced by the invasion of annual grasses, particularly Bromus tectorum. In experimental situations and in localized landscapes, prior studies have documented that biological soil crusts (biocrusts) can reduce annual grass presence and that biocrusts are highly vulnerable to phys...

On April 17th seven CALS members met at the Horseshoe Ranch Wildlife Area (HRWA) in Siskiyou County to collect and catalog the lichens of the area. A list of lichens present at the site are given. Notable lichens encountered include Lecanora neodegelii, Squamarina lentigera, Lobathallia alphoplaca and Umbillicara phaea var. coccinea.

This document and associated geospatial data were compiled to synthesize the published and unpublished information on Peltigera hydrothyria, a Forest Service Region 5 Sensitive Species. It does not represent a management decision by the U.S. Forest Service. Although the best and most current scientific information available was used, it is expected...

Preface This product has been a long time in coming! I think I first envisioned it back in 2001 as I was developing the idea of using a 'living map' concept. At that time, I was regularly attending meetings of the Governor's Sage Grouse Conservation Team and hearing complaints about the lack of detailed geographic information on vegetation in the s...

Bromus tectorum (cheatgrass) is an annual Eurasian grass that has invaded rangelands of the western USA. Being both a fire follower and a fire promoter, it can rapidly exclude native vegetation and is among the greatest threats to conservation in the region. Key to land management is a strong understanding of B. tectorum distribution and density. P...

While people experienced with lichen field work may easily locate hotspots of lichen diversity, other botanists, ecologists, and land managers may not. We sought to describe lichen hotspots in Pacific Northwest forests in terms of forest structure and environment. Additionally, we describe the varying lichen communities of different hotspot types a...

ABSTRACT ,The USDA Forest Health Monitoring project (FHM) includes studies of lichen communities because lichens directly relate to several forest resource issues, including concerns over air pollution. Previous FHM lichen studies inColorado culminated in a gradient model for the state which included environmental,characters and air quality. That w...

. We examined epiphytic macrolichen communities in Pseudotsuga menziesii (Douglas-fir) forests across the western Oregon landscape for relationships to environmental gradients, stand age and structure, and commercial thinning. We used a retrospective, blocked design through the Coast and the western Cascade ranges of Oregon. Each of our 17 blocks c...

The diverse lichen flora of the Pacific Northwest is being impacted by population growth and by forest management practices. Accumulating information about our lichen flora will improve our conservation strategies. This dissertation first collects information to improve our understanding of how lichen communities vary among forests of differing str...

Chaenothecopsis rubina, C. subparoica, and C. ussuriensis are reported new to North America, north of Mexico. Specimens corresponding to the taxonomically uncertain species, C. parasitaster and Microcalicium conversum, are also reported for North America, north of Mexico. Twenty-two species are reported as new to California, Oregon, or Washington.

Sulcaria badia, a rare lichen endemic to western North America, had not been collected since 1971 despite more than two decades of active field work in the area of the type location. A search was undertaken to determine the current range of the species. Sulcaria badia was found on hardwood trees, mainly Quercus garryana, up to 60 km inland, and in...

The new species Stenocybe fragmenta (Ascomycota, Mycocaliciaceae) is described from western North America. The species was collected from twigs of Cercocarpus montanus and Rhamnus purshiana. Stenocybe fragmenta is characterized by 5-7 septate, 18-30 xm long ascospores that fragment at maturity. This is the first report of spore fragmentation among...

The new species Stenocybe fragmenta (Ascomycota, Mycocaliciaceae) is described from western North America. The species was collected from twigs of Cercocarpus montanus and Rhamnus purshiana. Stenocybe fragmenta is characterized by 5–7 septate, 18–30 μm long ascospores that fragment at maturity. This is the first report of spore fragmentation among...

Sulcaria badia, a rare lichen endemic to western North America, had not been collected since 1971 despite more than two decades of active field work in the area of the type location. A search was undertaken to determine the current range of the species. Sulcaria badia was found on hardwood trees, mainly Quercus garryana, up to 60 km inland, and in...

Several exotic annual grass species are invading the Intermountain West. After disturbances including wildfire, these grasses can form dense stands with fine fuels that then shorten fire intervals. Thus invasive annual grasses and wildfire form a posi- tive feedback mechanism that threatens native ecosystems. Chief among these within Nevada are Bro...