Yellow cedar TPO 23

The reading and the lecture are about what causing yellow cedar to decline. The author of the reading feels that there are three theories which can be the cause of yellow cedar declination. However, the professor is not convinced of this. He casts doubts on each of the theories made by the author.

First, the author argues that cedar bark beetle might be one of the cause of yellow cedar declination. Cedar trees attack by the beetle and beetle larvae eat the wood. This specific point is challenged by the lecturer. He claims that yellow cedar are resistant to other species. Bark leaves are saturated with chemical substances which is poisonous to insects. Consequently, beetle attack cedar tree and they die due to poison on bark leaves.

Second, the writer contends that cedars declination reason could be brown bears, who sometimes claw at the cedars for its diet. The lecturer, however, refutes this by mentioning that brown bears do not cause cedars to decline. In fact, cedars are less in number all across of North America. He states that there are no bear on Island. So, bears are definitely not the cause of declination of cedars.

Finally, the author posits that climate may be causing declination of cedars and effect its root system. In contrast, the professor feels that cedars tree die when the climate is warm than in the winter. Moreover, more trees are dying in low elevation. Therefore, according to the lecturer, all these theories of the author are inadequate.