Friday, October 01, 2010

Beetle-killed trees probably less flammable than green trees

NASA Satellites Reveal Surprising Connection Between Beetle Attacks, Wildfire
The results may seem at first counterintuitive, but make sense when considered more carefully. First, while green needles on trees appear to be more lush and harder to burn, they contain high levels very flammable volatile oils. When the needles die, those flammable oils begin to break down. As a result, depending on the weather conditions, dead needles may not be more likely to catch and sustain a fire than live needles.


For some years Dave Neads has been pushing this point. Perhaps it takes an authority like NASA to get past the sceptics and vested interests. In 2004, in his series, The Other Side of the Story, he wrote:
On the bright side, once the trees are dead, they actually are less of a fire hazard than the green tree that used to stand so prettily in your garden. This is because all those oils and turpentines have left the tree needles, and they are actually not as prone to explosive crown fires as green trees.
One they reach the gray stage, they are very low risk for naturally occurring fires, but once felled, these naturally air dried trees make good firewood, so there may be a bonus if you have several of them on your property.
From Backyard Beetles by Dave Neads

Other posts by Dave Neads:

Dave's personal blog: Chilcotin Ark


Catherine Lee, Canada said...

Basically, what the post is saying is that green living trees are more flammable than dead withering rotting trees, right?

Jeffrey Newman said...

That's how I understand it: the oils in a conifer make it more flammable.