Treesearch

Tree allergenicity has been documented as a relevant ecosystem disservice, a tradeoff to the many co-benefits of urban trees. However, information on the allergenic tree dynamics in Neotropical urban environments is scarce. We used species-level Allergenic Potential Value (APV) and pollen-emission capacity as well as data on treestructure and diversity to explore the spatial dynamics of tree allergenicity in Bogota Colombia's public urban forest. We then statistically and spatially analyzed this data along with socioeconomic and vulnerability information to better understand tree allergenic...

Livestock grazing supports a considerable amount of economic activity across the United States. Federal grazing permits support numerous ranching operations by providing relatively low-cost grazing on federal lands. While grazing supports employment, labor income, and economic activity within a given state, the extent to which federal grazing permits play a role remains uncertain. In this paper we develop a method for estimating state-level economic contributions of livestock grazing for cattle grazing, as well as sheep and goat grazing, that is applicable to both the US Forest Service and...

We assessed attraction of pine engraver, Ips pini(Say) (Coleoptera: Curculionidae; Scolytinae), to pheromone-baited funnel traps treated with repellent semiochemicals in ponderosa pine, Pinus ponderosa var. scopulorumEngelm., forests in northern Arizona. Treatments included: 1) baited control (B, ipsdienol + lanierone), 2) 70 g of SPLAT Verb (a flowable, biodegradable formulation containing 10% verbenone, ISCA Technologies Inc., Riverside, CA, USA) + B, 3) 70 g of SPLAT Verb + (E)-2-hexen-1-ol+(Z)-2-hexen-1-ol + acetophenone + B, 4) 7.84-g verbenone pouch (Product #3413, Synergy Semiochemic...

California contains a diverse flora, and knowledge of the pathogens that threaten those plants is essential to managing their long-term health. To better understand threats to California plant health, a meta-analysis of Phytophthoradetections within the state was conducted using publicly available sequences as a primary source of data rather than published records. Accessions of internal transcribed spacer (ITS) ribosomal DNA were cataloged from 800 Californian Phytophthoraisolates, analyzed, and determined to correspond to 80 taxa, including several phylogenetically distinct provisional...

Long-term trends show increased tree mortality over the last several decades, coinciding with above-average temperatures, high climatic water deficits, and bark beetle outbreaks. California’s recent unprecedented drought (2012–2016) highlights the need to evaluate whether thinning and prescribed fire can improve individual tree drought resistance and reduce bark beetle-associated mortality. Using a thinning and prescribed fire study on the Stanislaus-Tuolumne Experimental Forest in the central Sierra Nevada implemented prior to the drought (2011–2013), we used dendrochronological methods...

Releasing several ecotypes or species of biological control agent is common in many biological control programs. However, the consequences of hybridization for fitness and host use of the resulting hybrids are difficult to predict, especially for hybrids between more than two species and with varying levels of introgression. Hybridization of biocontrol agents may increase or decrease fitness, with consequences for control efficacy. Additionally, hybridization may lead to changes in host use patterns that may put non-target host species at increased risk. We collected genomic data to...

Although recent large wildfires in California forests are well publicized in media and scientific literature, their cumulative effects on forest structure and implications for forest resilience remain poorly understood. In this study, we evaluated spatial patterns of burn severity for 18 exceptionally large fires and compared their cumulative impacts to the hundreds of smaller fires that have burned across California forests in recent decades. We used a burn severity atlas for over 1,800 fires that burned in predominantly conifer forests between 1985 and 2020 and calculated landscape...

Roads fragment animal populations, vehicles kill and injure animals, and traffic may affect animal behavior. Mitigation efforts (e.g., wildlife underpasses) are constructed to prevent fragmentation and reduce wildlife-vehicle collisions. However, little is known about traffic’s proximal effects on wildlife behavior and use of mitigation measures. We quantified the time that elk (Cervus elaphus) and white-tailed deer (Odocoileus virginianus) allocated to foraging, vigilance, and flight behavior before and after vehicle passage. Both species increased vigilance and flight behaviors and...

In North America, oaks (Quercus, Fagaceae) are the most abundant and diverse woody plants and one of the most highly valued, important forest trees as measured by provision of ecosystem services and economic value. Oaks dominate ecosystems throughout much of North America from Pacific Coast evergreen forests, to Eastern temperate deciduous forests, and southwestern oak‐piñon‐juniper woodlands (Johnson et al 2019). Many oak species are majestic, overstory trees but others are shrubs or small trees, particularly in drier habitats (e.g., chaparral), and higher elevation forests. Oaks grow in...

Vietnam mangrove forests have long been recognized to play important roles in coastal protection against soil erosion and storms/strong waves, supplying seafood, land reclamation, and carbon accumulation. Mangrove forests were severely damaged by the Second Indochina War and the shrimp aquaculture boom of the 1980s and 1990s. In recent decades, the rate of mangrove forest decline has been reduced due to increased efforts in mangrove restoration, though mangrove conversions to other land uses still occur locally. In this study, we analyzed Landsat data using the Google Earth Engine (GEE)...