Yellow Cedar Decline Hypotheses

Regarding the reading, the population of yellow cedar has become less due to three reasons. In contrast, the professor refuted all the author's reasons based on three concrete pieces of evidences.

First, that the more the insect parasite, the less the yellow cedar, based on what the reading claims, is refuted by the professor. He states that while the healthy yellow cedar secretes chemical substances as poisonous, it gets the beetle to die too. The fact of the matter is that unhealthy cedar is destroyed via other reasons than beetle.

Second, the reading states that brown bears get the number of cedar to diminish. Quite the reverse, the professor believes that since this kind of bear is not existed everywhere, it cannot be considered as the main reason of overall cedar decline. Indeed, should bears cause the decline of cedar, they should live in the whole related zones.

Third, according to the reading, in case of climatic changes, it leads to the devastation of yellow cedar. The professor casts doubt on this issue by saying that actually the number of dead cedar is more at lower level of land where the weather is warmer and also is less at higher level with cold climate. To illustrate more, change in climate make the yellow cedar sensible but not kill them at all.