Treesearch

Silviculture is the art, science and practice of controlling the establishment, composition, health, quality and growth of forests to accomplish a set of management objectives. This publication offers an approach to silviculture of the forests of Quintana Roo in which mahogany (Swietenia macrophylla King), the commercially most important tree species in Latin America, is found (Whitmore 2003). We designate these forests as mahogany forests. Much silvicultural knowledge has been gained by studying and observing which practices have or have not achieved the expected results in practice. This...

Can fire potential forecasts assist with pre-positioning of fire suppression resources, which could result in a cost savings to the United States government? Here, we present a preliminary assessment of the 7-Day Fire Potential Outlook forecasts made by the Predictive Services program. We utilized historical fire occurrence data and archived forecasts to assess how well the 7-Day Outlook predicts wildfire ignitions and escaped fires, ultimately to help characterize the effectiveness of this tool for prepositioning national firefighting resources. The historical fire occurrence data track...

Maps of the number, size, and species of trees in forests across the United States are desirable for a number of applications. For landscape-level fire and forest simulations that use the Forest Vegetation Simulator (FVS), a spatial tree-level dataset, or “tree list”, is a necessity. FVS is widely used at the stand level for simulating fire effects on tree mortality, carbon, and biomass, but uses at the landscape level are limited by lack of availability of forest inventory data for large contiguous areas. Detailed mapping of trees across large areas is not feasible with current technologie...

In arid and semiarid ecosystems, fire can potentially affect ecosystem dynamics through changes in soil moisture, temperature, and nitrogen cycling, as well as through direct effects on plant meristem mortality. We examined effects of annual and triennial prescribed fires conducted in early spring on soil moisture, temperature, and N, plant growth, and plant N content in semiarid shortgrass steppe. Annual burning increased soil inorganic N availability throughout the growing season, which was associated with increased soil temperature and a reduction in aboveground N in C3 plants. Furthermo...

Climate change is expected to have multiple direct and indirect impacts on ecosystems in the interior western U.S. (Christensen et al., 2007; IPCC 2013). Global climate predictions for the Southwest include higher temperatures, more variable rainfall, and more drought periods, which will likely exacerbate the ongoing issues relating to wildfire and water allocation in the region (Christensen et al., 2007). Of particular concern to managers are the effects of climate and related changes on riparian habitats, which support a disproportionate amount of the biodiversity in the region. The Rio...

Populations near many national forests and grasslands are rising and are outpacing growth elsewhere in the United States. We used National Visitor Use Monitoring (NVUM) data and U.S. census data to examine growth in population and locally based recreation visits within 50 and 100 miles of National Forest System (NFS) boundaries. From 1990 to 2010, the population living within 50 miles of NFS lands increased by 36 percent, from about 112 million to 153 million people; that population is expected to increase in the future. Recreation visits from local residents can be expected to increase by...

Fragmentation of the landscape, habitat loss, and fire suppression, all a result of European settlement and activities, have precipitated both the decline of Black-tailed prairie dog (Cynomys ludovicianus) populations and the occurrence of fire throughout the Great Plains, including the Shortgrass steppe of northeastern New Mexico. The presence of Black-tailed prairie dogs, a keystone species, and the occurrence of fire both play a vital role in maintaining the integrity and diversity of grassland ecosystems. In addition to serving as prey for the endangered Black-footed ferret (Mustela...

In semi-arid grasslands of the North American Great Plains, fire has traditionally been viewed as having few management applications, and quantitative measurements of fire behavior in the low fuel loads characteristic of this region are lacking. More recently, land managers have recognized potential applications of prescribed fire to control undesirable plant species and to manage habitat for wildlife in this region. Working in the shortgrass steppe of northeastern Colorado over a 7-year period, we quantified peak temperatures, heating duration, and heat dosage produced near ground level...

Among the ecosystem services provided by forests, wood provisioning takes a central position. Wood and derived products have played a critical role in the evolution of human kind and demand for raw material is increasing in a foreseeable future. Wood is used for energy production, construction and a wide variety of products for which different properties are required. Anatomical, chemical and physical properties of wood are determined through a complex process called xylogenesis controlled by internal and external signals and occurring during the life of the tree. In this chapter we...

We assessed tree cover using random points and polygons distributed within the administrative boundaries of Detroit, MI and Atlanta, GA. Two approaches were tested, a point-based approach using 1000 randomly located sample points, and polygon-based approach using 250 circular areas, 200 m in radius (12.56 ha). In the case of Atlanta, both approaches arrived at similar estimates of tree cover (50–53%) for both time periods, yet they show that roughly one-third of the tree-covered land area in 1951 was also tree-covered in 2010 and about 30–31% of the sampled land area lacked tree cover...