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

Essay topics:

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.

Essay topics in audio

The reading claims that the population of yellow cedar tree is declining and present some hypotheses to explain it. The lecturer argues against these hypotheses presented by the pasage and casts doubt about it with several reasons.

Fistly, the reading's claim that insect parasites, the cedar bark beetle, attack cedar trees killing them. The lecturer oposes this view stating that the health trees are more resistent to insects and trees produce poisoning chemicals for the insects. Also, the insects attack the damaged trees that would die anyway.

Secondly, the reading argues that brown bears are a reason to the decline of the trees by their agressive feeding habits. They may critically weaken the tree in order to eat the tree bark, leading them to die. The lecturer's claim that tree's population is declining on the islands as well but there are no bears living in the islands. The lecturer oposes the readind's claim by stating that brown bears can not be the reason for declining.

Ultimately, the reading's claim that the gradual change of climate have affected the root system of the yellow cedar. The early development of its root system lead them to flourish in the late winter, suffering then damage from the cold temperature that undermine the health of the whole tree. The lecturer oposes this view by stating that trees are dying more in places of lower elevation, where the temperature is higher, than in places of colder temperatures.

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Average: 8 (1 vote)
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2016-12-08 pires86 85 view
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Transition Words or Phrases used:
also, anyway, but, may, second, secondly, so, then, well

Attributes: Values AverageValues Percentages(Values/AverageValues)% => Comments

Performance on Part of Speech:
To be verbs : 8.0 10.4613686534 76% => OK
Auxiliary verbs: 3.0 5.04856512141 59% => OK
Conjunction : 4.0 7.30242825607 55% => More conjunction wanted.
Relative clauses : 11.0 12.0772626932 91% => OK
Pronoun: 21.0 22.412803532 94% => OK
Preposition: 28.0 30.3222958057 92% => OK
Nominalization: 4.0 5.01324503311 80% => OK

Performance on vocabulary words:
No of characters: 1221.0 1373.03311258 89% => OK
No of words: 242.0 270.72406181 89% => OK
Chars per words: 5.04545454545 5.08290768461 99% => OK
Fourth root words length: 3.94415379849 4.04702891845 97% => OK
Word Length SD: 2.36447783091 2.5805825403 92% => OK
Unique words: 132.0 145.348785872 91% => OK
Unique words percentage: 0.545454545455 0.540411800872 101% => OK
syllable_count: 365.4 419.366225166 87% => OK
avg_syllables_per_word: 1.5 1.55342163355 97% => OK

A sentence (or a clause, phrase) starts by:
Pronoun: 1.0 3.25607064018 31% => OK
Interrogative: 1.0 0.116997792494 855% => OK
Article: 12.0 8.23620309051 146% => 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: 12.0 13.0662251656 92% => OK
Sentence length: 20.0 21.2450331126 94% => OK
Sentence length SD: 29.732487843 49.2860985944 60% => OK
Chars per sentence: 101.75 110.228320801 92% => OK
Words per sentence: 20.1666666667 21.698381199 93% => OK
Discourse Markers: 4.66666666667 7.06452816374 66% => OK
Paragraphs: 4.0 4.09492273731 98% => OK
Language errors: 0.0 4.19205298013 0% => OK
Sentences with positive sentiment : 0.0 4.33554083885 0% => More positive sentences wanted.
Sentences with negative sentiment : 10.0 4.45695364238 224% => Less negative sentences wanted.
Sentences with neutral sentiment: 2.0 4.27373068433 47% => OK
What are sentences with positive/Negative/neutral sentiment?

Coherence and Cohesion:
Essay topic to essay body coherence: 0.202066317272 0.272083759551 74% => OK
Sentence topic coherence: 0.0807336776618 0.0996497079465 81% => OK
Sentence topic coherence SD: 0.0528421092838 0.0662205650399 80% => OK
Paragraph topic coherence: 0.130843505697 0.162205337803 81% => OK
Paragraph topic coherence SD: 0.0398812449005 0.0443174109184 90% => OK

Essay readability:
automated_readability_index: 12.4 13.3589403974 93% => OK
flesch_reading_ease: 59.64 53.8541721854 111% => OK
smog_index: 8.8 5.55761589404 158% => OK
flesch_kincaid_grade: 9.9 11.0289183223 90% => OK
coleman_liau_index: 12.01 12.2367328918 98% => OK
dale_chall_readability_score: 8.22 8.42419426049 98% => OK
difficult_words: 55.0 63.6247240618 86% => OK
linsear_write_formula: 8.0 10.7273730684 75% => Linsear_write_formula is low.
gunning_fog: 10.0 10.498013245 95% => OK
text_standard: 10.0 11.2008830022 89% => OK
What are above readability scores?

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Rates: 80.0 out of 100
Scores by essay e-grader: 24.0 Out of 30
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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.