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why so few hardwoods in the PNW?

Larry Caldwell larryc at teleport.com
Fri Aug 7 15:06:47 EST 1998

In article <35C97FEB.E092D7F1 at forestmeister.com>, 
redoak at forestmeister.com says...

> So, your oldgrowth forests are on average about 50 years old? <G>

No, on the *average* our old growth forests are about 100 years old.  
Some protected groves are older than that.  Of course, since we have 
started vigorous fire suppression in the last 50 years, our forests have 
gotten a lot older.  At least the ones that haven't been logged have.

Prior to modern fire suppression, the PNW had fire storms of biblical 
proportions on a regular basis.  A half a million acre forest fire was a 
common thing.

All the doug fir forests are fire regrowth.  Doug fir won't reproduce 
under a shade canopy, so you either have to burn it down or cut it down 
to get a doug fir forest.  The true old growth forests in the PNW are 
spruce and cedar, which are almost all within a narrow belt about 40 
miles wide near the Pacific coast.

> Wow, they sure must grow fast with all that rain to get so big in 50
> years.

Yes, they do grow fast.  A doug fir forest is about done growing in 100 
years.  By 120 years, fir no longer grows any taller, and the rings get 
pretty narrow too.  While a 20 year old tree is putting on half an inch 
to an inch a year diameter, a 100 year old tree will only grow a 
sixteenth of an inch a year.  

-- Larry

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