Populations of the yellow cedar, a species of tree that is common in northwestern North America, have been steadily declining for more than a century now, since about 1880. Scientists have advanced several hypotheses to explain this decline.
One hypothesis is that the yellow cedar decline may be caused by insect parasites, specifically the cedar bark beetle. This beetle is known to attack cedar trees; the beetle larvae eat the wood. There have been recorded instances of sustained beetle attacks overwhelming and killing yellow cedars, so this insect is a good candidate for the cause of the tree’s decline.
A second hypothesis attributes the decline to brown bears. Bears sometimes claw at the cedars in order to eat the tree bark, which has a high sugar content. In fact, the cedar bark can contain as much sugar as the wild berries that are a staple of the bears’ diet. Although the bears’ clawing is unlikely to destroy trees by itself, their aggressive feeding habits may critically weaken enough trees to be responsible for the decline.
The third hypothesis states that gradual changes of climate may be to blame. Over the last hundred years, the patterns of seasonal as well as day-to-day temperatures have changed in northwestern North America. These changes have affected the root systems of the yellow cedar trees: the fine surface roots now start growing in the late winter rather than in the early spring. The change in the timing of root growth may have significant consequences. Growing roots are sensitive and are therefore likely to suffer damage from partial freezing on clod winter nights. This frozen root damage may be capable of undermining the health of the whole tree, eventually killing it.
both the reading passage and the professor are discussing the hypothesis about the causes of yellow cedar's declining during the recent century. the reading passage claims that the cedar bark beetle, the brown bears and the gradual changes of climate are the feasible reasons for yellow cedar's decreasing. however, the lecturer finds all the ideas implausible and presents some evidence to refute them all and support the idea that none of the reasons mentioned in the passage can be considered possible explanation for this decline.
the reading passage holds the view that maybe the insect parasites, particularly the cedar bark beetle, are responsible for the cedar's decreasing since there have been some evidence which confirm the fact that beetle attacks adversely affect the yellow sedar and kills them. conversely the lecturer rejects the point in the reading and brings up the idea that healthy yellow cedars are much more resistant to insects than other species. they have powerful chemical which are poisonous to insects, so if the beetle attack the tree, it will damage itself and die. as a result this hypothesis seems to be really dubious.
furthermore, the other hypothesis on which the passage relies is that the brown bears maybe account for the decline because they feed from the tree bark which is superseded the wild berries,the bears main food and their improper and agressive feeding habits may cause the decline. on the contrary the professor takes the opposite view and underlines the fact that there is no bear on islands, while the cedar population have decreased as well in this place. therefore, regarding the fact that the decline occur in the places with and without bears, he assert that this hypothesis can't be the reason for the decline.
finally the last reason from the author's point of view is that the gradual changes of climate is a factor that can be considered as the possible reason for the decline. since these changes can adversely influence the roots of the cedar trees by means of causing them to grow in the late winter instead of in the early spring. in contrast, the speaker dismisses this issue due to the fact that the cedar trees primarily die at lower elevation where it is warmer rather than higher elevation where it is colder. in other words, more trees die in the relatively warm places where it is at the low elevation. consequently this claim doesn't possess a strong support in order to be acceptable.
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they have powerful chemical which are poisonous to insects,
they have powerful chemicals which are poisonous to insects,
the decline occur in the places
the decline occurs in the places
Sentence: furthermore, the other hypothesis on which the passage relies is that the brown bears maybe account for the decline because they feed from the tree bark which is superseded the wild berries,the bears main food and their improper and agressive feeding habits may cause the decline. on the contrary the professor takes the opposite view and underlines the fact that there is no bear on islands, while the cedar population have decreased as well in this place. therefore, regarding the fact that the
Error: agressive Suggestion: aggressive
flaws:
No. of Words: 416 250
Write the essay in 20 minutes. Less contents wanted from the reading passages but put more content from the lecture.
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Attribute Value Ideal
Score: 26 in 30
Category: Very Good Excellent
No. of Grammatical Errors: 2 2
No. of Spelling Errors: 1 2
No. of Sentences: 8 12
No. of Words: 416 250
No. of Characters: 2019 1200
No. of Different Words: 193 150
Fourth Root of Number of Words: 4.516 4.2
Average Word Length: 4.853 4.6
Word Length SD: 2.346 2.4
No. of Words greater than 5 chars: 144 80
No. of Words greater than 6 chars: 105 60
No. of Words greater than 7 chars: 55 40
No. of Words greater than 8 chars: 40 20
Use of Passive Voice (%): 0 0
Avg. Sentence Length: 52 21.0
Sentence Length SD: 32.241 7.5
Use of Discourse Markers (%): 0.75 0.12
Sentence-Text Coherence: 0.424 0.35
Sentence-Para Coherence: 0.687 0.50
Sentence-Sentence Coherence: 0.166 0.07
Number of Paragraphs: 4 4