Do Different Types of Leaves Burn Effectively?

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Discussion Overview

The discussion revolves around the effectiveness of different types of leaves in burning, particularly in the context of forest fires. Participants explore factors influencing combustion, such as moisture content and temperature, and differentiate between the burning of leaves and wood.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants question whether leaves burn effectively and under what conditions, noting that green leaves may not burn due to high water content.
  • It is suggested that dry leaves burn more effectively than wet leaves, with temperature playing a crucial role in the combustion process.
  • One participant explains that in forest fires, both leaves and wood can burn, with the heat from existing flames driving moisture out of nearby materials.
  • Another participant mentions that dry leaves are more exposed to oxygen, which facilitates burning, and that the process can lead to nearby trees igniting once they are sufficiently dried out.
  • A reference is made to the volatile compounds produced by trees, which can enhance burning, particularly when the tree is green rather than dry.
  • Concerns are raised about the safety of dry parts of trees, such as pine needles, in relation to fire hazards.

Areas of Agreement / Disagreement

Participants generally agree that moisture content significantly affects the burning of leaves, but there are competing views on the effectiveness of burning dry versus green leaves and the role of volatile compounds in combustion.

Contextual Notes

Participants discuss the influence of moisture and temperature on combustion without resolving the complexities of how different types of leaves and wood interact in fire scenarios.

Who May Find This Useful

This discussion may be of interest to those studying fire behavior, forest ecology, or anyone concerned with fire safety in relation to vegetation.

Blue Scallop
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do leaves burn? what kind of leaves burn? I tried burning a leaf but it won't burn.. but in forest fires.. is it the wood that burns or the leaves?
 
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Blue Scallop said:
do leaves burn? what kind of leaves burn? I tried burning a leaf but it won't burn.. but in forest fires.. is it the wood that burns or the leaves?
Depends on the temperature and how dry the leaves are. All leaves will burn in a hot enough fire.
 
Blue Scallop said:
do leaves burn? what kind of leaves burn? I tried burning a leaf but it won't burn..

Green leaves wont' burn because of how much water they have in them. Try a dry leaf instead.

Blue Scallop said:
but in forest fires.. is it the wood that burns or the leaves?

Both. The heat from a massive forest fire can easily boil away the water in leaves and other organic material and then set the leaves on fire.
 
Dry leaves will burn, wet leaves won't, the same is true of wet wood and dry wood.
In the case of a forest fire the first thing that happens is heat from stuff which already is burning drives out the moisture from nearby trees,
Once the water is gone these nearby trees will also start to burn.
The dry leaves go first because they are very exposed to atmospheric oxygen, which is why there is a fire in the first place.
It does't take long though for the wood to be dry enough to start burning as well.
 
http://wildfiretoday.com/2014/03/03/eucalyptus-and-fire/

Trees produce volatile compounds, some more than others, and burn better "green" rather than dry. The heat releases the compounds enhancing the burning process. Dry leaves will burn not so well. One should take notice of the caution when ornamenting a Xmas pine tree so that any part of the tree does not get hot enough to set forth a blaze, especially the pin leaves.
Forest fires are not really just the burning of dead old wood.
 

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