We're told that our nieces and nephews in Arkansas and Texas watch our blog from time to time because their moms and dads find it educational. So, this is about something we learned here at the Grand Canyon that we thought they would find as interesting as we did!
WHAT HAPPENS TO A FOREST AFTER A FIRE?
As we drove toward the Grand Canyon,we saw miles and miles of burned forest. Someone asked a ranger how long ago it happened and when the forest would grow back. The fire happened in 2006, but it looked like it happened a year ago, no more.
Here's the answer the ranger gave us and a couple of pictures:
Almost all of the trees in the forests around the Grand Canyon are made up of Ponderosa pines. (They're the dark green evergreens in the photos below.) They live for about 250 years. After a forest fire happens, like you can see in the two pictures below, however, they are not the first trees to come back. It takes quite a while for a ponderosa pine to germinate and come up as a sprout.
HOWEVER, the quaking aspen (the light green tree with the white trunks that you see in the photos) come in easily, and they spread very fast. In fact, only the first aspen in a grove has to grow from a seed. The rest of them are simply an extension of the root system of the first tree! That is, when you see a stand of aspen, you are looking at a large number of trees that all share exactly the same DNA; that is, they are virtually all the same tree!
Anyway, the aspen come in quickly and crowd out the ponderosa pines, which are slow to grow back. The aspen tree has a life expectancy of about 150 years. So - for about 150 years, all you have are big stands of aspen in the place where the wild fire took place. They are very beautiful. After 150 years, they die and make room for the ponderosa pines again, which now come back and re-populate the forest.
In two of the pictures below, you will see areas where there there have been good-sized forest fires. Can you see the small light green aspen trees coming up on these almost-bare hillsides? (You can click on each picture and it will come up larger on another page.) They're going to take over in a few more years. There are a few dark green ponderosa pines in the pictures, but they are the ones that survived the fire.
In addition to the pictures of the burned forests, there's a picture of Uncle Harold and Gaby who say "Hi!" They're sitting on the rim of the Grand Canyon, sunning themselves. It's a little cold here right now. In fact, last night it snowed a little!
Hope you enjoyed this story.
Love, Aunt Barbara
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