Taxus brevifolia “Pacific Yew” - Autre

The Pacific Yew is a native to the Pacific Northwest of North America (the area between the Pacific Ocean and the Rocky Mountains). Example of provinces and states such as B.C, Oregon, Washington (author last name, year). (organization, year) The reproduction cycle of the Pacific Yew is quite different from other reproduction cycles learned in class. This species is dioecious, meaning that the male and female, reproductive elements are on separate individuals (Roberts, 2011). In other words, Pacific Yew trees can be classified by females or males. This is different than some other gymnosperms where the male and female reproductive organs are on the same individual (monoecious). The reproduction cycle of the Pacific Yew is that the sporophyte produces either a megaspore (female) or microspore (male) from meiosis, and both of them develop into gametophytes through mitosis. The female megaspore is retained on the parent and 3 other microspores die (from the tetrad). While the microspore grows into the microgametophyte, and it releases sperms as pollen to reach the archegonia of the megagametophyte retained on the sporophyte and fertilizes the egg and eventually becoming the seed. The seed then undergoes mitosis and growth eventually become the sporophyte again and the cycle continues.

According to the Encyclopaedia Britannica (2011), Pacific Yew’s characteristics are that it is a medium to a large-sized tree (evergreen), which can grow between 5 o 15 meters tall and it has a trunk that can grow up to 50 cm wide. It is considered a gymnosperm and has needle-like leaves (modified) and produces a male and female cone. The male cones are round, while on the other hand, the female cones are modified and look like red berries. The Latin origin name of the plant is Taxus brevifolia. More commonly known as Pacific yew, California Yew, Oregon Yew, American Yew, or Western Yew. The family name of this plant species is Taxaceae (Earle, 2020).

The Pacific Yew is a very important and interesting species. People of the present and the past have used the plant for benefits. According to the Healing Power of Plants (2005), historically, the aboriginal people used the leaves of Pacific Yew as healing agents; they would crush up the leaves and directly apply it to wounds. Even more, they made tea from the needle leaves. Along with that, they used the bark of the tree for objects that needed to withstand strain such as fishhooks

and paddles. In recent days, the Pacific Yew has enormous importance for people as it is found to contain an anticancer chemical compound named paclitaxel. It treated diseases such as breast and ovarian cancer. The more common name for the chemical is Taxol, according to the Healing Power of plants (2005). After the discovery of this cancer healing chemical in the Pacific yew, people believed that the species would decline soon because of its demanding medicinal capabilities and because it grew very slowly. But luckily, people found a way to synthesize this chemical from other trees that grow much faster, which helped alleviate the issue of rapidly cutting down this species for their demand (Green, 2017)

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