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 cold winter nights. This frozen root damage may be capable of undermining the health of the whole tree, eventually killing it.
The reading passage and lecture have conflicting opinions about the causes of the decline in yellow cedar population. The article strongly postulates that the yellow cedar trees were subjected to consistent decline for more than a century. However, there are many assumptions would have explained this decline. On the other hand, the listening adamantly delinates that scientists still don't know the reason behind the yellow cedar decline. Also, none of the three theories are plausible.
First and foremost, according to the author of the excerpt, the yellow cedar would have subjected to insects attacks. In other words, there is an insect called cedar bark beetle that eats the yellow cedar wood. Nonetheless, the article offsets these points by insisting that the yellow cedar species are resistant to insects infection. The wood of the yellow cedar is saturated with a powerful chemical. which means those trees can't suffer from insects damage. Also, the beetles would have been attacking sick trees that already dead anyway.
On top of this, the professor further points out that brown bears could have caused damage to some trees. However, the decline in yellow cedar population was in all across. In the island, there were no bears and there is a decline. meaning that the bears weren't responsible for the yellow cedar decline. These claims refute the writer implication of how the brown bears attacking the yellow cedar for sugar would have destroyed the yellow cedar.
The article lastly asserts that the climate in northwestern North would have changed slowly over time. Subsequently, the roots of the yellow cedar root would have suffered from partial freezing. The speaker in lecture counters these points by insisting that frost damage happened more in warmer portions rather that colder one. which means more trees died in the lower elevations.
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Grammar and spelling errors:
Line 1, column 387, Rule ID: EN_CONTRACTION_SPELLING
Message: Possible spelling mistake found
Suggestion: don't
...amantly delinates that scientists still dont know the reason behind the yellow cedar...
^^^^
Line 3, column 405, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: Which
... is saturated with a powerful chemical. which means those trees cant suffer from inse...
^^^^^
Line 3, column 405, Rule ID: SENTENCE_FRAGMENT[1]
Message: “which” at the beginning of a sentence requires a 2nd clause. Maybe a comma, question or exclamation mark is missing, or the sentence is incomplete and should be joined with the following sentence.
... is saturated with a powerful chemical. which means those trees cant suffer from inse...
^^^^^
Line 3, column 429, Rule ID: CANT[1]
Message: Did you mean 'can't' or 'cannot'?
Suggestion: can't; cannot
...erful chemical. which means those trees cant suffer from insects damage. Also, the b...
^^^^
Line 5, column 233, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: Meaning
...e were no bears and there is a decline. meaning that the bears werent responsible for t...
^^^^^^^
Line 5, column 256, Rule ID: EN_CONTRACTION_SPELLING
Message: Possible spelling mistake found
Suggestion: weren't
...re is a decline. meaning that the bears werent responsible for the yellow cedar declin...
^^^^^^
Line 7, column 330, Rule ID: UPPERCASE_SENTENCE_START
Message: This sentence does not start with an uppercase letter
Suggestion: Which
...warmer portions rather that colder one. which means more trees died in the lower elev...
^^^^^
Line 7, column 330, Rule ID: SENTENCE_FRAGMENT[1]
Message: “which” at the beginning of a sentence requires a 2nd clause. Maybe a comma, question or exclamation mark is missing, or the sentence is incomplete and should be joined with the following sentence.
...warmer portions rather that colder one. which means more trees died in the lower elev...
^^^^^
Transition Words or Phrases used:
also, anyway, first, however, lastly, nonetheless, so, still, in other words, on the other hand
Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments
Performance on Part of Speech:
To be verbs : 10.0 10.4613686534 96% => OK
Auxiliary verbs: 7.0 5.04856512141 139% => OK
Conjunction : 3.0 7.30242825607 41% => More conjunction wanted.
Relative clauses : 12.0 12.0772626932 99% => OK
Pronoun: 16.0 22.412803532 71% => OK
Preposition: 32.0 30.3222958057 106% => OK
Nominalization: 4.0 5.01324503311 80% => OK
Performance on vocabulary words:
No of characters: 1572.0 1373.03311258 114% => OK
No of words: 299.0 270.72406181 110% => OK
Chars per words: 5.25752508361 5.08290768461 103% => OK
Fourth root words length: 4.1583189471 4.04702891845 103% => OK
Word Length SD: 2.35603952624 2.5805825403 91% => OK
Unique words: 156.0 145.348785872 107% => OK
Unique words percentage: 0.521739130435 0.540411800872 97% => OK
syllable_count: 473.4 419.366225166 113% => OK
avg_syllables_per_word: 1.6 1.55342163355 103% => OK
A sentence (or a clause, phrase) starts by:
Pronoun: 1.0 3.25607064018 31% => OK
Article: 12.0 8.23620309051 146% => OK
Subordination: 0.0 1.25165562914 0% => More adverbial clause wanted.
Conjunction: 0.0 1.51434878587 0% => OK
Preposition: 5.0 2.5761589404 194% => OK
Performance on sentences:
How many sentences: 20.0 13.0662251656 153% => OK
Sentence length: 14.0 21.2450331126 66% => The Avg. Sentence Length is relatively short.
Sentence length SD: 29.2647825893 49.2860985944 59% => The essay contains lots of sentences with the similar length. More sentence varieties wanted.
Chars per sentence: 78.6 110.228320801 71% => OK
Words per sentence: 14.95 21.698381199 69% => OK
Discourse Markers: 4.75 7.06452816374 67% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 8.0 4.19205298013 191% => OK
Sentences with positive sentiment : 3.0 4.33554083885 69% => OK
Sentences with negative sentiment : 11.0 4.45695364238 247% => Less negative sentences wanted.
Sentences with neutral sentiment: 6.0 4.27373068433 140% => OK
What are sentences with positive/Negative/neutral sentiment?
Coherence and Cohesion:
Essay topic to essay body coherence: 0.330932497993 0.272083759551 122% => OK
Sentence topic coherence: 0.103430309271 0.0996497079465 104% => OK
Sentence topic coherence SD: 0.054992557762 0.0662205650399 83% => OK
Paragraph topic coherence: 0.210731593502 0.162205337803 130% => OK
Paragraph topic coherence SD: 0.0600448293256 0.0443174109184 135% => OK
Essay readability:
automated_readability_index: 10.8 13.3589403974 81% => Automated_readability_index is low.
flesch_reading_ease: 57.27 53.8541721854 106% => OK
smog_index: 3.1 5.55761589404 56% => Smog_index is low.
flesch_kincaid_grade: 8.8 11.0289183223 80% => OK
coleman_liau_index: 12.64 12.2367328918 103% => OK
dale_chall_readability_score: 8.19 8.42419426049 97% => OK
difficult_words: 73.0 63.6247240618 115% => OK
linsear_write_formula: 6.5 10.7273730684 61% => OK
gunning_fog: 7.6 10.498013245 72% => OK
text_standard: 9.0 11.2008830022 80% => OK
What are above readability scores?
---------------------
Rates: 75.0 out of 100
Scores by essay e-grader: 22.5 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.