Here’s
what the botanists have to say about the 2008
Leaf-Peeping Season in Plumas County:
There’s a bit of debate among Plumas National
Forest botanists over whether the year’s dry
weather will hasten or delay the onset of fall
color, or have no impact on the usual timing of
things. (Every year people will always say “it’s
coming earlier”, but we’re convinced that’s just
due to aging and perception! It’s mostly about
change of daylight.)
However, the experts agree the best color will
come from trees and shrubs closer to riparian
and drainage areas, while other species such as
chokecherry and Big-leaf Maple may be drier and
may show signs of stress.
“Down along the rivers where plants have roots
in the water [and] won’t be affected,” says
botanist Jim Belsher-Howe of the Mt. Hough
Ranger District. “That’s why we
always have color in our area – fortunately
we’re at the top of the watershed.”
 He
predicts species like Indian rhubarb -- (shown
here along Deer Creek in 2006 photo taken
by Jim Hardwick ) -- creekside dogwood,
cottonwoods and willows, along with aspens, will
turn out the best color. So be sure to include
drives and walks that follow streams and lakes.
Botanist/Ecosystems Manager Linnea Hanson
predicts that the foliage viewing in the Feather
River Canyon (Hwy. 70) and Deer Creek Canyon
(Hwy. 32) will still be good, despite the fires
that occurred there this summer.
“Most of it doesn’t look too bad, it’s kind of
amazing,” she said. “There’s pockets where it’s
crowned, but other places where there’s just an
underburn; the ground got scorched but all the
trees were left, and the hardwoods should be
turning.”
Why do leaves change color?
Shorter periods of daylight and variations in
temperature are the cues for deciduous
(leaf-shedding) plants to prepare for winter.
They begin to shut down their food-making
process (photosynthesis) and the production of
the green pigment chlorophyll. The plants
attempt to store up their chemicals by taking
out sugars and chlorophyll from their leaves.
This slowing allows yellow and gold pigments
(called carotenoids) to slowly emerge – which
have been there all along but are masked by
chlorophyll. Red pigment (called anthocyanin),
unlike the others, is not attached to the leaf
cells, but is produced by sugars in the leaf
veins, which are trapped when veins are closed
during the fall. The intensity of the red
pigment varies depending on the sugar
concentration and acidity in the cell sap, and
the amount of sunlight the
leaves receive. The best combination for
producing intense autumn colors is dry, sunny
days followed by cool (not freezing) dry nights.
When fall weather is cloudy and rainy, and the
nights warm, the color is usually less intense.
What the plants can’t store, they must deal with
as waste. They form a special layer of cells
that severs the tissues supporting the leaves at
the branch, causing the leaves to drop.
The yearly process doesn’t happen overnight, and
unpredictable weather makes each fall foliage
season unique. Varying microclimates among
ridges and valleys generally make for a long
fall color season in Plumas County, with “peaks”
occurring at different times in different areas.
The best time to spot the most color, however,
is usually the third week of October.
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