Treesearch

In coniferous western forests, recent widespread tree mortality provided opportunities to test the long-held theory that forest cover loss increases water yield. We reviewed 78 studies of hydrologic response to standing-replacing (severe wildfire, harvest) or nonstand-replacing (drought, insects, low-severity wildfire) disturbances, and reassessed the question: Does water yield or snowpack increase after forest disturbance? Collective results indicate that postdisturbance streamflow and snowpack may increase, not change, or even decrease, and illuminate factors that may help improve...

Achieving successful outplanting of trees on increasingly harsher sites is a global concern. In Chile, for example, new Eucalyptus globulus plantations are being targeted to poorer, low fertility sites where additional stresses often negatively affect seedling performance during the first field season. Nitrogen-loading during the later stages of nursery production can, however, significantly improve seedling physiological performance on harsher sites by increasing plant growth and nutrient storage reserves for subsequent root growth after outplanting. Maximizing these benefits, and...

The coarse roots of Pinus ponderosa included in the cage are the ones most involved in tree stability. This study explored the variations in traits, such as volume, cross-sectional area, and radius length of cage roots, and used those data to develop a mathematical model to better understand the type of forces occurring for each shallow lateral root segment belonging to different quadrants of the three-dimensional (3D) root system architecture. The pattern and intensity of these forces were modelled along the root segment from the branching point to the cage edge. Data of root cage volume...

Background: Fire size and severity have increased in the western United States in recent decades, and are expected to continue to increase with warming climate. Habitats for many species are threatened by large and high-severity fires, but the effect of spatial scale on the relationship between fires and habitat modifications is poorly understood. We used the 2011 Wallow Fire - the largest wildfire in the state history of Arizona, USA - as a case study and assessed changes in predicted nesting habitat of the threatened Mexican spotted owl (Strix occidentalis Xántus de Vésey) in the first...

Within the realms of both wildland and prescribed fire, an understanding of how fire severity and forest structure interact is critical for improving fuels treatment effectiveness, quantifying the ramifications of wildfires, and improving fire behavior modeling. We integrated high resolution estimates of fire severity with multi-temporal airborne laser scanning data to examine the role that various fuel loading, canopy shape, and other variables had on predicting fire severity for a complex of prescribed fires and one wildfire and how three-dimensional fuels changed as a result of these...

Forested black ash (Fraxinus nigra) wetlands are an important economic, cultural, and ecological resource in the northern Great Lake States, USA, and are threatened by the invasive insect, emerald ash borer (Agrilus planipennis Fairmmaire [EAB]). These wetlands are likely to experience higher water tables and warmer temperatures if they are impacted by large-scale ash mortality and other global change factors. Therefore, it is critical to understand how temperature, hydrology, and their interaction affect greenhouse gas fluxes in black ash wetland soils. In order to predict potential...

In October, the vast majority of the United States housing construction and sales markets were positive on both month-over-month and year-over-year bases. The exceptions were the yearly single-family under construction and total spending data categories. New single-family house sales and private residential construction spending recorded monthly declines.

In November, the vast majority of the U.S. housing construction and sales markets were positive on a month-over-month and year-over-year basis. New single-family housing under construction, multifamily housing completions, and single-family construction spending recorded year-over-year decreases. Total single- and multifamily completions and existing house sales recorded monthly declines.

In September, United States single-family construction data indicated month-over-month improvement in several critical categories, with the exception being completions. Total housing starts, permits, and completions were negative month-over-month. Only total and single-family under construction were positive on a monthly and yearly basis. Of note, total and single-family construction spending continued year-over-year declines. Declining interest rates have led to improving housing affordability, which is one factor for this month’s improvement.

May 2019 U.S. housing data were largely negative, with only total housing permits, single-family permits, multifamily under construction, and existing sales positive on a month-over-month basis. The year-over-year data were similar, with only total under construction, single-family under construction, and single-family completions being positive.