Big Sur is a volatile
land. Surfaces in canyons rise and
fall. Yet, redwoods survive. It appears
that they do so by adapting to the individual
habitats canyon by canyon. In some canyons
redwoods will grow clusters of branches on a
changed surface, such as growing branches downward
to the surface ground, then growing upward when the
branches seek light. In McWay Canyon this is
conspicuous and the forest near the front of the
canyon resembles the forest of Ichabod
Crane.
Botanically, Big Sur is an
incredibly rich area. Many of the greatest
pioneer naturalists poured over this coastal area
making “discoveries” such as sugar pine, ponderosa,
and Santa Lucia fir, and making the area
scientifically famous.
Southern Coastal
Habitat Different
In Northern California only
five percent of the original old-growth redwood
population remains, and considerable habitat has
diminished because of human impact.
Unlike their northern
brethren, Big Sur redwoods grow in discontinuous
patches. These outpost groves collect the flow of
fog in stream valleys and along north facing slopes
up to 4,000 feet. These “great mists” lend a
mystical quality to this coast throughout the
summer season. The fog creates a
greenhouse-like envelope for the redwoods by
increasing humidity and lowering
temperatures.
Coast redwoods are specially
adapted to rake delicate droplets of moisture from
the ethereal vapors. This adaptation is so
efficient that Big Sur’s redwoods harvest thousands
of gallons of water every foggy morning. Thus, Big
Sur’s redwoods make their own climate and their own
“rainfall,” enabling them to survive where we would
not expect –even along watercourses that go
dry in the summer. All they need is a valley where
the summer fog flows.
In this land of little rain,
redwoods, a temperate rain forest species, are the
most visibly prevalent tree. Because of deep
submarine canyons offshore and ocean currents that
draw cold upwellings from the depths, there is a
lot of fog, and redwoods gain most of their
nutrients from fog. Their needles are
exquisitely designed to trap and hold moisture from
the fog, then drip that moisture on their immediate
surroundings. Arboreal duff from the trees
drops there, too, and builds up to create a
sponge-like, water-holding mat.
Foggy coastal areas have been
virtually immune to fire. But with the
vegetation changes in the upper elevations, coastal
redwoods are becoming more vulnerable to
fire. In the recent Basin Complex event, fire
invaded nearly every canyon in the mid-coast.
Many redwoods were lost and others were mortally
damaged.
Genetically
Distinct?
Genetic diversity of coastal
redwoods in their southernmost habitat is known to
be vast. But not much else is known.
Just by casual observation of the external
characteristics of these trees, this diversity is
obvious. From canyon to canyon these cloning
colonies look different. Each family of
redwoods will have strikingly similar external
characteristics.
We wonder if this is because
of the long life of their isolated adaptation to
each immediate environment. We propose to
document the differences with photography and a
complete ecology report for each redwood canyon,
and a representative study of the redwood colonies
in higher reaches of the Santa Lucia coastal
mountain range.
In Big Sur, the southernmost
range of coastal redwoods, historic habitat and
redwoods remain nearly intact. That is, until
recently. Now the habitat remains mostly
intact, but the population of trees is appears to
be less. Actual numbers and habitat
identities are only estimated, and both need to be
reliably documented.
Mortal
Redwood
We don’t know the actual age
of each tree. In these canyons many
enumeration’s of a tree are often exposed by
changes in the ground surface by earthquake or
erosion. Is it the same tree if one
enumeration has grown from another which now only
contains dead cells? Or is this a kind of
clonal sequence age?
Redwoods clone themselves in
these environments, reproducing by asexual
sprouting rather than by sexual pollination with
seeds from cones. There are many enumerations
of one redwood in the canyons, so one tree which
would appear to be many different trees would
actually be the clonal expression of one tree with
an age of 10,000, or 20,000 years or
more.
These trees are remarkably
resilient. To avert a cancerous strain in the
main stem, they can grow a burl as a refugium for
good cells. From this refugium they can wait
out the cancer or grow a new branch which can
become a main stem.
Also, at an early stage of
its growth, a redwood often will create a burl with
a bank of its genes. This appears to be a way
for the tree to sprout new trees with its
genes. In cases of massive environmental
alteration, such as with fires and mudflows, these
gene banks provide a way to continue their
population.
As they adapt for the
topography and disease, the redwood develops new
genes for survival which are reflected in external
characteristics. In time, over many
enumerations of the tree becoming a cloned family,
all the redwoods in this family will appear very
similar.
All of this is obvious.
Not much else is known about the redwoods in their
southernmost habitat. Most of what we think
we know is inferred from what we know about their
northern brethren.
Coast Redwoods, sequoia
sempervirens, once covered an enormous reach across
northern latitudes, and have presided in this
region for more than 20 million years. How
they have survived in this southern outpost of
their range is necessary to understand if we are to
protect them.
The whole picture of this
tree living here is an incredible scenario.
The land emerged from the sea with very little to
attract such an amazing species as the
redwood. Other amazing species luxuriate in
higher habitats. But in the redwood habitats
this tree has come to make a home for itself in a
wild canvas of serendipitous choreography.
This tree, with its density and mammoth size,
making it the greatest terrestrial biomass on the
planet, grows in its inhospitable environment
because of a chance encounter with a neighborly
ocean.
The coast redwood family
becomes a primeval forest in a rocky desert
canyon. As if to give back to the ocean,
redwoods respire at night to replenish the
understory and feed the springs and streams which
flow to the sea. When an enumeration of a
redwood is toppled by wind, lightning or fire, it
slowly embellishes the soil, houses animals and
vertebrates, and nurtures other plants.
Fire
Historically, redwoods have
prospered with natural protection in shady, moist
canyons. Before the modern era of fire
suppression big fires occurred in rough intervals
averaging seventy years or so. Nowadays, fire
occurs at much more frequent intervals. Epic
Big Sur conflagrations now happen in intervals of
less than ten years.
In higher elevations fire
occurred more frequently, about every twenty years,
but these were light and served to enhance the
reproductive abilities of plant communities. These
also served to reduce fuels near redwood
forests.
Through First Peoples and
early Settler eras, patches of the Santa Lucia
coastal range burned every year. Settlers and
miners increased the intensity of burning. In
some years there were big fires, notably 1894 and
1903. The largest fire consumed 50,000
acres. Once the U.S. Forest Service took
control of the range in 1907, fire was suppressed.
At first, fires were held to an average of
8,000 acres burned each year. With an ever
increasing effectiveness, the total that burned
each year was reduced to an average of only 400
acres by the 1960s.
Then, after seventy years of
suppression, which allowed a massive build up of
fuels, increasingly frequent and bigger fires
began. Some groves were burned to
death. According to Henson and Usner (1993)
in The Natural History of Big Sur, conifer forests
throughout the Coast Range have been reduced by
wildfire (p. 236). Restriction of other
conifer stands has caused redwood colonies to
diminish. Conifer habitat that couldn’t
regenerate killed trees has been replaced by scrub
ecosystems that don’t nourish redwood
habitat.
Many trees were burned simply
out of ignorance &emdash;even in the recent Basin
Complex Fire. Even though the local fire
manual instructs that redwoods be protected, many
were deliberately set on fire during “backfiring”
operations.
Redwoods have become
increasingly susceptible to mortal fire as they are
subjected to repeated fires and the debris build up
that follows. The brush against a redwood
burns very hot and attacks the tree’s
interior.
Redwoods that have burned
internally to some degree are susceptible to very
hot fires that can completely gut a tree.
Near Pheneger Creek an old redwood burned
internally which was not visibly evident. But
inside it burned very hot straight up and exited
through an opening 35-40 feet up the tree and
flames shot out like a blow torch.
After the Basin Complex Fire
in 2008, a geomorphologist proposed that coastal
property owners construct “grizzly snags.”
The snags were proposed to stop or slow down
erosion and debris flow. Even though it was known
that redwoods don’t have taproots and are likely to
move, the nets would be bolted to old redwoods on
slopes.
Big Sur redwoods were logged
extensively in low lying easily accessed valleys
and canyons in the last years of 1800s and early
1900s. Mills were established locally and
shakes were cut by hand and shipped to Monterey and
King City.
Somehow, a community will to
save the redwoods emerged. State Parks and
Save the Redwoods League were invited to
memorialize coastal redwood groves.
International designations of special recognition
for these redwood ecological systems have been
bestowed on these trees and their
habitat.
When fire enters a redwood,
through a “goose pen,'” “cat eye,” or from beneath,
the tree the flammable interior is exposed.
After two or more fires, the tree can be burned
from the inside and die. This does not seem
to be known by public agencies that fight
fire. Rather than protect redwoods, as all
forest management plans instruct for fire
suppression, these agencies allow redwoods to burn,
and even “back fire” through redwoods. In the
2008 fire, fires were set by fire fighting crews
and sent upslope which causes the most intense and
damaging fire.
What we need to learn
This project, Big Sur Redwood
Preservation Study, is proposed to learn how these
redwoods have learned to survive here
–despite human influence on this fragile coast
which has caused diminishment of their habitat and
their numbers.
So isolated from their
northern brethren are these redwoods that the
classic questions of relatedness come to mind.
Should these trees be considered a subspecies or
special variety of the coastal redwood? We
don’t know that for sure because there has not been
sufficient study.
- How many redwoods are
there in how many habitats in this southernmost
extent of their range?
- How do they differ from
canyon to canyon, and how do they differ from
the main body of redwoods in the northern
counties of the State?
- What comparable data from
other periods corresponded with historic
conditions?
- If we can find this data,
can we project future redwood populations?
- What scientific
enterprises are going on now to understand the
development of genetic diversity in other
redwood populations and how they may be
relevant?
- How can redwoods be
protected from the ravages of too much, too-hot
fire?
The expert premise is that a certain sort of fire,
light, frequent and not excessively hot – like the
kind of fire Native American cultures husbanded –
suppressed the buildup of hot burning fuel
concentrations. Therefore fire, in the right
context and prescription, is distinctly a friend to
the redwoods – under the right
conditions.
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