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 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 insectis 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 cold winter nights. This frozen root damage may be capable of undermining the health of the whole tree, eventually killing it.
The reading and listening materials have a debate on potential reasons that caused an enormous population decrease on yellow cedar. The author argues three possible reasons however the following speaker refutes each one of them.
First, the author argues that insect parasites especially cedar bark beetle are responsible for massive declines. The speaker refuses this by saying that healthy trees are resistant to parasites. They create and excrete chemicals that are poisonous to parasites. Their barks and leaves are saturated with these chemicals. Due to the fact that healthy cedars are unlikely to suffer from insect damage this argument is not valid.
Second, the author points out another reason, brown bears. The author explains that these bears sometimes claw at cedars in order to eat the tree barks. The speaker explains that it is true that bears sometimes damage trees, however, there are declines all over the north-west and off coastal regions where there are no bears what so ever. As a result, this argument is also false.
Lastly, the author suggests that yellow caders decline should be attributed to climate changes, Which make the root grows in later winter instead of early spring. The speaker accepts that climate changes can effect yellow caders and make them become more sensitive to damages, However, he further explains that there should be less or no decline in low elevations which have warmer and more suitable weather but the evidence contradictory shows otherwise.
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Grammar and spelling errors:
Line 5, column 46, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...d, the author points out another reason, brown bears. The author explains that th...
^^
Line 5, column 346, Rule ID: WHITESPACE_RULE
Message: Possible typo: you repeated a whitespace
Suggestion:
...re there are no bears what so ever. As a result, this argument is also false. ...
^^
Transition Words or Phrases used:
also, but, first, however, lastly, second, so, it is true
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 12.0 10.4613686534 115% => OK
Auxiliary verbs: 3.0 5.04856512141 59% => OK
Conjunction : 8.0 7.30242825607 110% => OK
Relative clauses : 14.0 12.0772626932 116% => OK
Pronoun: 22.0 22.412803532 98% => OK
Preposition: 21.0 30.3222958057 69% => OK
Nominalization: 4.0 5.01324503311 80% => OK
Performance on vocabulary words:
No of characters: 1267.0 1373.03311258 92% => OK
No of words: 240.0 270.72406181 89% => More content wanted.
Chars per words: 5.27916666667 5.08290768461 104% => OK
Fourth root words length: 3.93597934253 4.04702891845 97% => OK
Word Length SD: 2.34555948668 2.5805825403 91% => OK
Unique words: 154.0 145.348785872 106% => OK
Unique words percentage: 0.641666666667 0.540411800872 119% => OK
syllable_count: 390.6 419.366225166 93% => OK
avg_syllables_per_word: 1.6 1.55342163355 103% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 4.0 3.25607064018 123% => OK
Article: 9.0 8.23620309051 109% => OK
Subordination: 1.0 1.25165562914 80% => OK
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 0.0 2.5761589404 0% => More preposition wanted as sentence beginning.
Performance on sentences:
How many sentences: 13.0 13.0662251656 99% => OK
Sentence length: 18.0 21.2450331126 85% => The Avg. Sentence Length is relatively short.
Sentence length SD: 65.0713763775 49.2860985944 132% => OK
Chars per sentence: 97.4615384615 110.228320801 88% => OK
Words per sentence: 18.4615384615 21.698381199 85% => OK
Discourse Markers: 4.38461538462 7.06452816374 62% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 2.0 4.19205298013 48% => OK
Sentences with positive sentiment : 1.0 4.33554083885 23% => More positive sentences wanted.
Sentences with negative sentiment : 7.0 4.45695364238 157% => OK
Sentences with neutral sentiment: 5.0 4.27373068433 117% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.165043206788 0.272083759551 61% => OK
Sentence topic coherence: 0.0496213144134 0.0996497079465 50% => OK
Sentence topic coherence SD: 0.0419578050405 0.0662205650399 63% => OK
Paragraph topic coherence: 0.0894180201855 0.162205337803 55% => OK
Paragraph topic coherence SD: 0.0103813107208 0.0443174109184 23% => Paragraphs are similar to each other. Some content may get duplicated or it is not exactly right on the topic.
Essay readability:
automated_readability_index: 12.7 13.3589403974 95% => OK
flesch_reading_ease: 53.21 53.8541721854 99% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 10.3 11.0289183223 93% => OK
coleman_liau_index: 13.34 12.2367328918 109% => OK
dale_chall_readability_score: 8.61 8.42419426049 102% => OK
difficult_words: 62.0 63.6247240618 97% => OK
linsear_write_formula: 7.0 10.7273730684 65% => OK
gunning_fog: 9.2 10.498013245 88% => OK
text_standard: 9.0 11.2008830022 80% => OK
What are above readability scores?
---------------------
Rates: 80.0 out of 100
Scores by essay e-grader: 24.0 Out of 30
---------------------
Note: the e-grader does NOT examine the meaning of words and ideas. VIP users will receive further evaluations by advanced module of e-grader and human graders.