Cork
Cork - the thick bark of the cork oak tree (Quercus suber) - is a remarkable material. It is
tough, elastic, buoyant, fire-resistant, and suitable for a wide range of
purposes. It has also been used for millennia: the ancient Egyptians sealed
the sarcophagi (stone coffins) with cork, while the ancient Greeks and Romans
used it for anything from beehives to sandals.
And the cork oak itself is an extraordinary tree. Its bark grows up to 20 cm in
thickness, insulating the tree like a coat wrapped around the trunk and
branches and keeping the inside at a constant 20°C all year round. Developed
most probably as a defense against forest fires, the bark of the cork oak has a
particular cellular structure - with about 40 million cells per cubic
centimeter - that technology has never succeeded in replicating. The cells are
filled with air, which is why the cork is so buoyant. It also has an elasticity
that means you can squash it and watch it spring back to its original size and
shape when you release the pressure.
Cork oaks grow in several Mediterranean countries, including Portugal,
Spain, Italy, Greece, and Morocco. They flourish in warm, sunny climates where
there is a minimum of 400 millimeters of rain per year and no more than 800
millimeters. Like grape vines, the trees thrive in poor soil, putting down deep
roots in search of moisture and nutrients. Southern Portugal’s Alentejo region
meets all of these requirements, which explains why, by the early 20th century,
this region had become the world’s largest producer of cork, and why today it
accounts for roughly half of all cork production around the world.
Most cork forests are family-owned. Many of these family businesses, and indeed
many of the trees themselves, are around 200 years old. Cork production is,
above all, an exercise in patience. The planting of a cork sapling to the
first harvest takes 25 years, and a gap of approximately a decade must separate
harvests from an individual tree. And for top-quality cork, it’s necessary to
wait a further 15 or 20 years. You even have to wait for the right kind of summer’s
day to harvest the cork. If the bark is stripped on a day when it’s too cold - or
when the air is damp - the tree will be damaged.
Cork harvesting is a very specialized profession. No mechanical means of
stripping cork bark has been invented, so the job is done by teams of highly
skilled workers. First, they make vertical cuts down the bark using small sharp
axes, then lever it away in pieces as large as they can manage. The most
skillful cork- strippers prise away a semi-circular husk that runs the length of
the trunk from just above ground level to the first branches. It is then dried
on the ground for about four months, before being taken to factories, where it
is boiled to kill any insects that might remain in the cork. Over 60% of cork
then goes on to be made into traditional bottle stoppers, with most of the
remainder being used in the construction trade, Corkboard and cork tiles are
ideal for thermal and acoustic insulation, while granules of cork are used in
the manufacture of concrete.
Recent years have seen the end of the virtual monopoly of cork as the material
for bottle stoppers, due to concerns about the effect it may have on the
contents of the bottle. This is caused by a chemical compound called
2,4,6-trichloroanisole (TCA), which forms through the interaction of plant
phenols, chlorine, and mold. The tiniest concentrations - as little as three or
four parts to a trillion - can spoil the taste of the product contained in the
bottle. The result has been a gradual yet steady move first toward plastic
stoppers and, more recently, to aluminum screw caps. These substitutes are
cheaper to manufacture and, in the case of screw caps, more convenient for the
user.
The classic cork stopper does have several advantages, however. Firstly, its
traditional image is more in keeping with that of the type of high-quality goods with which it has long been associated. Secondly - and very importantly -
cork is a sustainable product that can be recycled without difficulty.
Moreover, cork forests are a resource that supports local biodiversity, and
prevents desertification in the regions where they are planted. So, given the
current concerns about environmental issues, the future of this ancient
material once again looks promising.
Questions 1-5
Do the following statements agree with the information given in the Reading
Passage?
In boxes 1-5 on your answer sheet, write
TRUE if the statement agrees with the
information
FALSE if the statement contradicts the
information
NOT GIVEN if there is no information on this
1. The cork oak has the thickest bark of
any living tree.
2. Scientists have developed a synthetic cork with
the same cellular structure as a natural cork.
3. Individual cork oak trees must be left for 25
years between the first and second harvest.
4. Cork bark should be stripped in dry atmospheric
conditions.
5.
The only way to remove the bark from cork oak trees is by hand.
Questions
6-13
Complete
the notes below. Choose ONE WORD ONLY from the passage for each answer. Write
your answers in boxes 6-13 on your answer sheet.
Comparison
of aluminum screw caps and cork bottle stoppers
Advantages
of aluminum screw caps
• do not affect the 6
..........................of the bottle contents
• are 7 ..........................to produce
• are 8 ..........................to use
Advantages
of cork bottle stoppers
• suit the 9 ..........................of
quality products
• made from a 10 ..........................material
• easily 11 ..........................
• cork forests aid 12
..........................
• cork forests stop 13
.......................... happening
Answers in detail:
1. NOT GIVEN
Question: The cork oak has the thickest bark of any living tree.
Key words: thickest bark
In paragraph 1 and paragraph 2, the author mentioned the thick bark of the cork oak tree as “a remarkable material” and “its bark grows up to 20 cm in thickness”. This information does not mean that it is “the thickest bark of any living tree”.
In addition, in True/ False/ Not given tasks, the questions follow the order of the text, so if you are not sure about your answer, you can find the answer to question 2. It is in the second sentence of paragraph Therefore, you just need to pay attention to the previous parts. There is no statement showing any comparison between the cork oak’s bark with that of other living trees. We have no information about this statement.
2. FALSE
Question: Scientists have developed a synthetic cork with the same cellular structure as natural cork.
Key words: a synthetic cork, the same cellular structure, natural cork
In paragraph 2, the writer mentioned the cellular structure of the bark of the coak oak “the bark of the cork oak has a particular cellular structure – with about 40 million cells per cubic centimeter – that technology has never succeeded in replicating”. The technology can refer to the scientists here. The fact that they “never succeeded in replicating” means that they have not been able to make a copy of the natural cork, with all of the same qualities. So the answer is False.
– Develop with the same structure = replicate
3. FALSE
Question: Individual cork oak trees must be left for 25 years between the first and second harvest.
Key words: individual, 25 years, the first and second harvest
In paragraph 4, the author mentioned the harvesting of an individual cork oak tree. He/ she wrote “From the planting of a cork sapling to the first harvest takes 25 years, and a gap of approximately a decade must separate harvests from an individual tree”. Therefore, the period of 25 years is the period from the planting to the first harvest, while the gap between the first and the second harvest is about 10 years (approximately a decade).
– Between = gap
– The first and second harvest = separate harvests
4. TRUE
Question: Cork bark should be stripped in dry atmospheric conditions.
Key words: stripped, dry atmospheric conditions
We need to find information about the cork bark being stripped. Following the order of the text, we can see in the paragraph 4, the author mentioned “If the bark is stripped on a day when it’s too cold – or when the air is damp – the tree will be damaged”. Therefore, the bark should not be stripped in damp atmospheric conditions; however, in contrast, it should be stripped in dry atmospheric conditions. The answer is True.
– The air = atmospheric conditions
5. TRUE
Question: The only way to remove the bark from cork oak trees is by hand.
Key words: only way, remove, by hand
In paragraph 5, the author claimed “No mechanical means of stripping cork bark has been invented, so the job is done by teams of highly skilled workers.” In this sentence, “stripping cork bark” means “remove the bark”. Since the author stated that “no mechanical means has been invented”, we can understand that they do not use any machines in removing the bark, so it has to be done by hand (the hands of highly skilled workers). The answer is True.
– Remove = strip
– By hand = done by workers, no mechanical means
6-13 FILL IN THE BLANKS
6. taste
Question: do not affect the ……… of the bottle contents
Key words: affect, bottle contents
The author mentioned “Recent years have seen the end of the virtual monopoly of cork as the material for bottle stoppers, due to concerns about the effect it may have on the contents of the bottle…..The tiniest concentrations – as little as three or four parts to a trillion – can spoil the taste of the product contained in the bottle. The result has been a gradual yet steady move first towards plastic stoppers and, more recently, to aluminium screw caps.” It means that aluminium screw caps overcame one disadvantage of cork bottle stoppers, which is that they “spoil the taste of the product contained in the bottle”. Therefore, aluminim screw caps do not affect the taste of the product inside the bottle. The answer is “taste”.
– Affect = spoil
– Bottle contents = the product contained in the bottle
7. cheaper
Question: are ……… to produce
Keyword: produce
8. convenient
Question: are ……….. to use
Key word: use
In the last sentence of paragraph 6, “These substitutes are cheaper to manufacture and, in the case of screw caps, more convenient for the user”. “These substitutes” refer to “aluminium screw caps” and “Manufacture” refers to “produce”, while “for the user” means “to use”. So they are cheaper to produce and more convenient for the user. But the question requires “one word only”, so the answer for question 8 has to be “convenient”.
– Produce = manufacture
– To use = for the user
9. 9. image
Question: Suit the ………. of quality products
Key words: suit, quality products
We find information about quality products in this sentence: “Firstly, its (the cork bottle stopper) traditional image is more in keeping with that of the type of high quality goods with which it has long been associated”. “in keeping with” means “suit”. So the blank has to be “traditional image”, but the answer allows one word only, so it has to be “image”
– Products = goods
– In keeping with = suit
10. Sustainable
Question: made from a ………. Material
Key words: made from, material
11. recycled
Question: easily ………….…
In the next sentence, the write mentioned “Secondly – and very importantly – cork is a sustainable product that can be recycled without difficulty”. Recycling often is associated with the material. So the author is referring to its material here. The answer is “sustainable” and “recycled”
– Easily = without difficulty
12. Biodiversity
Question: cork forests aid ………..
Key words: cork forests, aid
13. desertification
Question: cork forests stop ………… happening
Key words: cork forests, stop
The last sentence mentioned the cork forests – “Moreover, cork forests are a resource which support local biodiversity, and prevent desertification in the regions where they are planted. So, given the current concerns about environmental issues, the future of this ancient material once again looks promising”. “Support” means “aid” and “prevent” is equal to “stop”. So the answers have to be “biodiversity” and “desertification”
– aid = support
– stop = prevent