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Forests:
Nearly 5% of New York City street trees die every year.
Urban trees are usually planted where it fits, not where it is most suitable for them!
Often the concrete has already been laid, so crews tear out a 4-by-4 foot piece of concrete, put in
a 4 by 4 by 4 plant and hope for he best!
The average life of a tree in urban environment is 4 to 7 years, a real disaster if one considers that
trees, in good conditions, can live many centuries! What a waste!
The problems are:
Insufficient soil and nutrients for growth; insufficient space for the root structure to grow (either
roots crack the sidewalk or their growth will be stunted); insufficient water or excess water in the
tree pit; insufficient oxygen: tree roots need enough air to capture a sufficient amount of carbon
dioxide to convert ©arbon into Oxygen.
Furthermore, the salt used to treat roads, especially when it snows, damages the tree; the heat as
well: concrete radiates heat and the reflections from the shops panes are not good either. Bumps
and bruises damage the trees since people are in the habit of tying heavy objects such as bicycles
to them. Pollution plays its role: smog, ozone, and urine.
Finally, a road or sidewalk joint repair severs roots, especially those of older trees that are more
sensitive; roots of young trees can still grow back. Some trees however still thrive in cities going
to 15 years of age! But is that enough?
Knowing what precedes, what advises and solutions would you provide for the urban architect
who designs towns?
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But this is not all. Americans are so interested in very big things that the Sequoia trees
can well be in danger. When the biggest trees in the world are discovered, people come to see
them from all over the US and from abroad. Tourists destroy other trees by using their cars
around the non-frequented paths, bringing buses of tourists, and walking around the trees, so the
earth becomes packed around the roots, making it impossible for the trees to breathe through their
roots.
What do you think of this craze about the tallest trees in the world? If you were a forest guard,
what would be your attitude? Would you try to hide the trees, mislead people by giving them
false directions or would you create ways of making them happy without endangering the trees?
Propose your solutions in both cases:
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Deforestation is a crucial problem on Earth since we draw the oxygen that we breathe
from the forest, plants and algae. Many species from the fauna and flora have already
disappeared due to this problem.
While temperature forests slightly expand due to reforestation and abandonment of marginal
farmlands, tropical forests are shrinking rapidly and 1 or 2 species are lost every day. People
look for tropical forest wood because the quality of the wood is good, and the countries that sell it
do not have fixed regulations concerning cutting down trees. If they have regulations, these
countries are developing countries and need the money, or they are so corrupted that they can do
whatever suits their greed.
In 1990, Brazil cut down 8 million of hectares of trees.
In the 1900’s, it has been estimated that 20 million square km of tropical lands covered with
canopy forest existed, i.e., an area twice as big as the US.
200,000sq km are cleared each year due to farmers and commercial logging or fuel wood
gathering.
However, some countries made a real effort to counteract deforestation.
China reforested 4.5 million hectares per year during the last decade.
Korea and the Soviet Union seem to have reforested effectively.
Annual timber growth in the US now exceeds harvest by 37%. The number of wooded acres in
the US has grown by 20% between the 70’s to the 90’s. This is most encouraging, but still there
is much to do concerning the protection of Nature.
Total closed
forest area
(thousands of
hectares)
Annual clearing
rate
Annual
reforestation
% lost
annually
Brazil
India
Indonesia
Ivory
Coast
Malaysia
357,480
36,540
113,895
4,458
20,996
8,000
1,500
900
290
255
561
173
164
8
25
2.2
4.1
0.8
6.5
1.1
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