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Author Topic: Why is the new growth a different color/colour?  (Read 2433 times)

Offline Geezer

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Why is the new growth a different color/colour?
« on: 23/06/2011 01:45:51 »
We've had an unusually wet Spring this year in the Pacific Northwet, and the weeds trees are loving it. The new growth on fir trees is quite obvious because the needles are a much lighter shade of green (no comments about Procol Harum, please).

Why's that then?
« Last Edit: 23/06/2011 02:15:14 by Geezer »


 

Offline CliffordK

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Why is the new growth a different color/colour?
« Reply #1 on: 23/06/2011 03:54:24 »
Geezer,

Are you growing WEED in your garden?

No wonder you are seeing odd colors!!!!!!!!!!!
 

Offline Geezer

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Why is the new growth a different color/colour?
« Reply #2 on: 23/06/2011 06:20:30 »
Schtum! Schtum! I thought we agreed not to discuss that.
 

Offline CliffordK

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Why is the new growth a different color/colour?
« Reply #3 on: 23/06/2011 08:54:03 »
Fir trees in particular have light colored new growth, and darker older needles.  However, the contrast between new and old growth is obvious in many leafy plants too. 

The new growth in fir tends to be very soft, while the older growth is woody.

Perhaps the old growth is more heat tolerant, so it has more concentrated chlorophyll.  The young growth may require more moisture, and would potentially be less heat tolerant, and thus would have less chlorophyll, and would reflect more light.

Consider what would happen if you exposed a fir branch to intense conductive heat (hot air), from an oven, or a fire.  I would guess that the young growth would be damaged quicker than the older growth.  Likewise, the tree can likely keep the young growth cooler from solar radiative heat by using lighter colors.
 

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Why is the new growth a different color/colour?
« Reply #3 on: 23/06/2011 08:54:03 »

 

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