Plants that changed the world: “Pines”
Kiri Degon takes a look at the adaptable tree that supplies much of the world’s furniture, paper and Christmas decorations.
Pines are conifer trees mostly native to the northern hemisphere. There are 115 types of pine, found in regions including Scandinavia, Canada, Alaska and as far south as northern Africa, Sumatra and China. Pines have been – and continue to be – used in many ways, from food to construction material.
Pine species can grow from 3 to 80 meters tall, with the majority averaging 15–45 m. They have four different types of leaf – seed leaves, juvenile leaves, scale leaves and needles, each representing a different age of the tree. Pines live a long life, typically reaching ages of 100 or even 1,000. The oldest known pine is a Great Basin bristle-cone pine named Methuselah, which is around 4,600 years old. Methuselah is one of the world’s oldest living organisms and can be found growing high in the White Mountains of Inyo County, eastern California.
Pines are a robust tree and this is reflected in their wide-ranging reproductive methods. Seeds from pines can be small with wings, dispersed by the wind, or they can be larger and dispersed by birds. When the tree reaches maturity, its cones open and release the seeds, although in some of the bird-dispersed species, the bird has to crack the cone open.
Other species (such as Canary Island pine and Bishop pine) have cones that are sealed shut by resin and can only be opened in particular (hot) conditions. This means that while forest fires can be devastating for ecology, in some cases they can actually help regenerate pines, melting the cones’ resin and releasing the seeds to grow new trees.
Throughout history, all parts of the pine tree have been used by civilizations across the world in an array of ways.
Wood from pines is soft, light and malleable, which has made it popular for commercial timber, particularly for furniture and pulp wood used for paper. The bark, sap and resin can act as natural band-aids, while needles can be used to make baskets, trays and pots (they also serve as food for a variety of moths and butterflies).
Around the Himalayas, pine forests are regarded as spiritual places and even host religious festivals. Here, pines are used to treat asthma through breathing in the forest air; seeds are used as a source of oil; and cones are used for decorations.
Native Americans used the tree bark as a food source. The white inner bark was consumed either in raw slices as a snack, or by grinding it up to a powder to use as flour or thickener for soups and stews. The inner bark is high in vitamins A and C, and thus has also been used for medicinal healing. Other medicinal properties of pine include being antiseptic, inflammatory and antioxidant, and often the needles are used to make tea to combat colds and flu.
The best-known use of pine trees, especially in the West, is indoors, adorned in fairy lights and surrounded by presents each December. Each year around 8 million pines are sold in the UK as Christmas trees, with close to 60 million currently being grown across Europe, for an average growing time of seven years.
Pine trees are also grown for other ornamental purposes, and the cones are commonly used for crafts and decorations.
Recent scientific research has suggested that the smell of forest pine can limit climate change. Researchers found that the scented vapours coming off the trees turn into aerosols above the trees. The aerosol particles reflect sunlight back to space, helping clouds to form which promote cooling in the atmosphere. So, as well as keeping our rooms smelling fresh and cool, the aroma of pine could also help the whole world keep cooler.