Trees that fight with fire

Pines love fire almost as much as we do. While we tend to think of fire as destructive, most members of the pine family depend upon it for their very survival. Some pines use a strategy whereby they quickly grow thick fire-resistant trunks so they can weather any fires that blaze through their forest and then take advantage of all the sunlight that becomes available when their neighbors burn. Other pines load themselves with ducts of flammable resin that transform them into living sticks of dynamite. When these types of pines are around, small fires become raging infernos that clear away other species and pave the way for fireproof pine seeds waiting in the soil to grow and take over a forest. The trouble is, we've had no idea when pines started depending upon fire in these ways. Now a new fossil, the oldest pine ever discovered, is revealing that this relationship has existed since the beginning.

140 million year old pine specimen. The "fc" stands for "fire crack." 

140 million year old pine specimen. The "fc" stands for "fire crack." 

We suspected from previous molecular studies that the close relationship between pines and fire arose during the days of the dinosaurs over 66 million years ago. This seemed logical since the dinosaurs were around at a time when atmospheric oxygen levels were very high and fires would have sparked quite easily but we've had no fossil evidence to support the idea. The new pine specimen, which dates to a whopping 140 million years ago, now provides the evidence we've been missing because it actually was preserved by being charred in a fire. What is even more fascinating is that the fossilised wood clearly shows the presence of flammable resin ducts just like those that are used by modern pines to turn small fires into huge ones. This makes it look like pines have been wielding fire as a weapon to dominate forests for as long as they have been around. 

The paper revealing all of these findings published in Geology in March, 2017. 

Banner image courtesy of the US Bureau of Land Management.