Paper Details  
 
   

10 Pages
2506 Words

 
   
   
    Filter Topics  
 
     
   
 

Create a new account

It's simple, and free.

Effect of Forest Fires

Tree canopies are killed when their crowns are heated above a lethal temperature of 60 to 70 degrees Celsius (Johnson, 1992, p. 5053). Fire may also kill trees by girdling stems, and by scorching or consuming leaves, needles, and buds. While, architecturally, it might appear that conifers burn more easily due to their smaller diameter branches, in the northern reaches of North America crown fires usually result in complete tree mortality (Johnson, 1992, p. 57).

Only occasionally do jack, red, and white pine survive these conflagrations. This is because of their thicker bark and generally greater crown base. Furthermore, upon surviving one fire, the rapid growth rate of these trees quickly elevates any remaining crown to safer levels.

In contrast, black and white spruce are easily killed by fire. This is because of their smaller branches and exposed buds, as well as their thin bark and lower crown base heights. Furthermore, aspens also have thin bark. Because of this fact, aspens are killed by even short periods of heating of the basal cambium (Johnson, 1992, p. 57).

The high intensity fires of the north also consume large amounts of forest floor (Johnson, 1992, p. 97). As a result, large areas of mineral soil is often left exposed. This phenomenon, however, promotes forest growth. All northern tree species seedlings do well in mineral soils (Johnson, 1992, p. 100).

Farther south, hardwood fires can actually enhance forest growth. These forests often have a dense understory of shrub species (Patterson, 1992, p. 34). The shade tolerant plantsmany of which have been imported from other parts of the worldcan make survival difficult for deciduous seedlings. "Cool" surface fires of the hardwood forests clear out this shrub layer (Reich et al., 1990, p. 2179). Furthermore, they tend to have a lesser effect on the larger trees, and may actually increase nutrient availability. Thus, fires in hardwood fore...

Page 1 of 10 Next >

    More on Effect of Forest Fires...

    Loading...
APA     MLA     Chicago
Effect of Forest Fires. (1969, December 31). In LotsofEssays.com. Retrieved 20:56, December 20, 2014, from http://www.collegetermpapers.com/viewpaper/1303578906.html
 
Copyright © 1999 - 2014 CollegeTermPapers.com. All Rights Reserved. DMCA