Search results
Results from the WOW.Com Content Network
The Trees of North America. For the purposes of this category, "North America" is defined in accordance with the World Geographical Scheme for Recording Plant Distributions (WGSRPD), which calls it Northern America, namely as one of the nine "botanical continents". It includes the following regions:
Once one of the largest ecosystems in North America, from Virginia south to Florida and west to Texas, it now occupies less than a quarter of the original range. Degradation of the ecosystem is partially due to excessive timber harvesting, urbanization, and fire exclusion. Although the ecosystem is heavily fragmented at present, it still ...
Fire is the dominant type of disturbance in boreal North America, but the past 30-plus years have seen a gradual increase in fire frequency and severity as a result of warmer and drier conditions. From the 1960s to the 1990s, the annual area burned increased from an average of 1.4 to 3.1 million hectares per year.
Ponderosa pine forest is a plant association and plant community dominated by ponderosa pine and found in western North America. It is found from the British Columbia to Durango, Mexico . [ 1 ] In the south and east, ponderosa pine forest is the climax forest , while in the more northern part of its range, it can transition to Douglas-fir or ...
Flowering big bluestem, a characteristic tallgrass prairie plant. The tallgrass prairie is an ecosystem native to central North America.Historically, natural and anthropogenic fire, as well as grazing by large mammals (primarily bison) provided periodic disturbances to these ecosystems, limiting the encroachment of trees, recycling soil nutrients, and facilitating seed dispersal and germination.
Los Cabos Plains and Hills with Low Tropical Deciduous Forest and Xeric Shrub 14.6.2: La Laguna Mountains with Oak and Conifer Forests 15: Tropical Wet Forests: 15.1: Humid Gulf of Mexico Coastal Plains and Hills 15.1.1: Gulf of Mexico Coastal Plain with Wetlands and High Tropical Rain Forest 15.1.2: Hills with Medium and High Evergreen ...
Hypothesized fire regimes of natural communities in the United States. Grassy woodlands have regimes of a few years: blue, pink, and light green areas. Pre-Columbian woodlands of North America , consisting of a mixed woodland-grassland ecosystem, were maintained by both natural lightning fires and by Native Americans before the significant ...
Natural surface fire patterns are especially important in pine reproduction. [6] Biotic factors affecting forests take the form of fungal outbreaks in addition to mountain pine beetle and bark beetle infestations. [15] These beetles are particularly prevalent in North America and kill trees by clogging their vascular tissue. [14]