|← Climate Change||A Social Behavior →|
The Bristol-Myers drug company wants to harvest the Pacific Yew, biologically known as Taxus brevifolia. It is an indigenous coniferous tree found in the Pacific of North America, ranging from the southernmost Alaska to central California with other species distributed in other parts of the world including India and China. It is an evergreen tree and is covered with leaves throughout the year. Pacific yew is usually medium or small sized; grows up to a height of ten to fifteen meters with its trunk rarely more than fifty centimeters in width. It has a thin peeling bark which is brown in color and bears thinning leaves that are dark green in color.
The tree contains an important substance called taxol that is used for cancer treatment. Taxol is a brand name for the anticancer drug called paclitaxel. The amalgam paclitaxel found in the bark of tree possess properties that aid in stabilizing microtubule and maintain the shape of the cell and help in cell division. Taxol is contained primarily in the bark of the yew trees that are about ten inches or more in diameter.
The drug taxol is valuable to humans because it is a treatment of various types of Cancer, especially the ovarian and breast cancer. Some communities use the drug for treating male potency, and its leaves are boiled and consumed in order to alleviate internal body pains. Members of the Cowlitz community crush the leaves and then apply its pulp to their external wounds. The Quinault people, however, chew the yew leaves and sputter them on the wounds in order to heal them.
The tree grows naturally in forests of the temperate climate zones in northern hemisphere. In its natural environment, the tree serves as food for the elk, the deer and other game animals. The community around the forest depends on these animals for feeding their families. It has an ornamental potential as a shade tree, for topiary and for hedges.
Currently, thirty pounds of the bark produces one gram of taxol, and since the trees are fairly small, one and a half trees are required to get a gram of taxol. A patient requires about 500 milligrams of taxol per every course of treatment, and four courses are necessary; making it a total of two grams per patient; which amounts to three trees to treat one person.
The Quinault Indians use this tree to for making traditional ceremonial crafts such as arrows, bows, masks and others. They also made spoons, needles, canoe bailers, dishes, various tools to handle and sharp pointed tools. It was also used to make digging sticks to unearth clams and roots; and to prepare tokens for gambling. Pacific yew was also used for medicinal purposes such as making salves for skin disease, skin cancer, as well as chest poultices for bronchitis. The native Americans brewed the plant’s needles and barks as a tea to relieve dizziness, headache, fever, colds, rheumatism, internal injuries, arthritis and scurvy, as well as for kidney, stomach and lung problems. It has also been used in its natural form, to treat tuberculosis, kidney problems ulcers, liver dysfunction and digestion problems. Pacific yew has also been used as dietary supplement for many thousands of patients.
90 % of the yew trees are of a diameter smaller than optimum size for collection.The optimum size preferred by the bark collectors is a width that is above ten inches diameter.
The drug company cannot just collect the bark of the tree because removing the bark of a tree means killing the whole tree; it cannot survive without the bark.
The reason why the company cannot grow the yew tree in a farm is because it produces only few seeds which can only germinate after being eaten and passed out by some animal. The plant takes very long to mature and must be about a hundred years old before its bark is harvested which makes it hard for them to grow it in farms.
This has led to destruction of many wild populations that depend on the plant for food also people have started searching for related species of plants of the genus Taxus that may contain taxol.