TPO 23 integrated yellow cedar trees are declining because of three main reasons first insect parasites especially the cedar bark beetles second the brown bears third the gradual change of climate

The article asserts that the population of the yellow cedar has been decreasing since one hundred years ago and provides three explanations for it. The educator, on the other hand, completely disagrees with all three rationalizations made by the author and insists that none of them are robustly adequate. In the following, the professor's justifications will be explained thoroughly.

First of all, the reading claims that some insect parasites, especially the cedar bark beetles, have caused this decline. However, the lecturer refutes this assumption, mainly because he thinks that healthy yellow cedar trees are much more resistant to parasites than other trees. As an illustration, the balk of these trees are saturated by chemicals which are poisonous for insects. Moreover, he declares that although the beetles have ruined some damaged or seek trees, they are not the fundamental cause of the whole decline.

Secondly, the essay assumes that brown bears may have caused the decline since they eat the sweet bark of these trees by clawing them. Nevertheless, the teacher refutes this perception insomuch as he upholds all trees in northwestern of North America are declining both in mainland and islands and no bears are living in islands; therefore, interestingly, this cannot be a main cause of the decline.

Tertiary, the passage concurs that as the climate has gradually changed, the roots of these trees have been becoming more sensitive which is a critical factor of their decline. The professor opposes this presumption owing to the fact that he claims that this impact on the roots of the trees are basically substantial on high elevations of the location where is colder relatively, but the trees are also dying at low elevations with warmer weather. Therefore, this may not be the main cause of the decrease.