Treesearch

Fire occurring in the chaparral behaves as a crown fire, a dual-layer fire that typically ignites in a dead surface fuel layer and transitions to an elevated live crown layer where it continues to spread. In chaparral fuels including chamise, a dominant species in southern California, flame transition to live crown fuels is associated with higher spread rates and greater fire intensity. Despite the relative importance of surface-to-crown transition and crown fire spread, most fire models represent chaparral fire as surface fire, therefore omitting key behavior processes driving this fire...

Native forests of Hawaiʻi Island are experiencing an ecological crisis in the form of Rapid ʻŌhiʻa Death (ROD), a recently characterized disease caused by two fungal pathogens in the genus Ceratocystis. Since approximately 2010, this disease has caused extensive mortality of Hawaiʻi's keystone endemic tree, known as ʻōhiʻa (Metrosideros polymorpha). Visible symptoms of ROD include rapid browning of canopy leaves, followed by death of the tree within weeks. This quick progression leading to tree mortality makes early detection critical to understanding where the disease will move at a...

Climate change is affecting natural resources globally, altering ecosystems that support outdoor recreation. In the western United States, effects such as warming temperatures, increased drought, reduced snowpack, and widespread wildfires will change the outdoor recreation landscape. In this article, we synthesize the state of science regarding the effects of climate change on outdoor recreation in the western US and summarize adaptation options that can reduce the consequences of climate change, considering the adaptive capacities of recreationists and managers. We draw from a series of...

Land managers in the Lake Tahoe basin are considering increasing the use of prescribed fire and forest thinning to restore conditions that will be more resilient to wildfires. However, such restorative treatments also constitute disturbances that could increase sediment and nutrient loads. We examined whether the water-quality impacts from future treatments are likely to be lower compared to the potential impacts from future wildfires under various climate change scenarios. We applied an online interface for the Water Erosion Prediction Project (WEPP) model in combination with a landscape...

Climate change will accelerate forest mortality due to insects, disease, and wildfire. As a result, substantial resources will be necessary where and when forest managers seek to maintain multiple management objectives. Because of the increasing managerial requirements to offset climate change and related disturbances, the uncertainty about future forest conditions is magnified relative to climate change alone. We provide an analytical approach that quantifies the key drivers of forest change—climate, disturbance, and forest management—using scenarios paired with simulation modeling to...

Across the United States, wildfire severity and frequency are increasing, placing many properties at risk of harm or destruction. We quantify and compare how different forest management strategies designed to increase forest resilience and health reduce the number of properties at risk from wildfire, focusing on the Lake Tahoe Basin of California and Nevada. We combine landscape change simulations (including climate change, wildfire, and management effects) with scenarios of current and plausible fuel treatment activities and parcel-scale fire risk analysis. Results suggest that more...

Cities in the Latin America and Caribbean (LAC) region and around the world are setting long-term greening goals that include planting more trees and increasing green cover. Research in LAC cities has mainly focused on biodiversity and vegetation, with little understanding of the mechanisms underlying the decisions through which stakeholders achieve urban greening. Exploring stakeholders’ views about urban forest management and governance can provide us with an opportunity to identify needs and research gaps for urban greening and urban forestry in LAC. To our knowledge, there has never...

Little is known about how spatial literacy influences mapping and decision-making related to environmental management and ecosystem services. We assessed the role of spatial landscape literacy in participatory environmental management and ecosystem service assessments in peri-urban Bogota, Colombia. Spatial landscape literacy (SL) was evaluated by testing stakeholder’s ability to locate specific landscapes and landmarks. We then assessed if opinions on environmental decisions and ecosystem services were significantly related to SL. We used an online instrument to capture 2,397 respondent’s...

Sugar pine, Pinus lambertianaDouglas, is a keystone species of montane forests from Baja California to southern Oregon. Like other North American white pines, populations of sugar pine have been greatly reduced by the disease white pine blister rust (WPBR) caused by a fungal pathogen, Cronartium ribicola, that was introduced into North America early in the twentieth century. Major gene resistance to WPBR segregating in natural populations has been documented in sugar pine. Indeed, the dominant resistance gene in this species, Cr1, was genetically mapped, although not precisely. Genomic...

The frequency of large, high-severity “mega-fires” has increased in recent decades, with numerous consequences for forest ecosystems. In particular, small mammal communities are vulnerable to post-fire shifts in resource availability and play critical roles in forest ecosystems. Inconsistencies in previous observations of small mammal community responses to fire severity underscore the importance of examining mechanisms regulating the effects of fire severity on post-fire recovery of small mammal communities. We compared small mammal abundance, diversity, and community structure among...