Trees have long been important to us, not just for their natural beauty and character, but also because through the ages they have been central to our existence in numerous ways. We have lived with them and among them for millennia and they continue to feed us, shelter us and inspire us. They supply many of the vital ingredients for life – food, medicine, timber, oils, resins and spices – and also ecological services such as providing the oxygen we breathe, controlling soil erosion, trapping pollution, acting as carbon sinks and increasing water purity, as well as moderating the climate. Scientists often refer to these benefits as ‘natural capital’. In addition to providing such benefits, trees have also become the subjects of song, poetry, stories and art, and they are woven into our religions, folklore and customs. They act as direct links to our history and can exert a powerful influence over our imaginations and memories.
The commonest botanical description of a tree is a plant that has a self-supporting perennial woody stem. It does not have to be tall or reach a certain age, and indeed some trees grow as shrubs or as dwarfed species and some are quite short-lived. The definition of a tree is surprisingly open to interpretation, and varying descriptions can be found – hence the variations sometimes quoted for the total number of tree species in the world. We use a wider definition of what constitutes a tree and in our book, Remarkable Trees, we have included some palms too, even though they do not produce secondary growth in their stems (they are monocotyledons), and so could not be called ‘woody’. However, self-supporting perennial species such as the coconut fill very similar niches to woody trees in the habitats in which they grow and we wanted to include their fascinating stories.
One estimate is that there are around 60,000 species, from the dragon’s blood tree growing in the arid landscapes of Socotra to mangroves that live happily in saltwater
Trees are a very diverse group of plants, found around the world in an amazing variety of forms and sizes and growing in a great range of habitats. One estimate is that there are around 60,000 species, from diminutive sub-arctic tundra types including birches to towering tropical hardwoods like mahogany, and from the dragon’s blood tree growing in the arid landscapes of Socotra to mangroves that live happily in saltwater. Trees are remarkable examples of evolution, having developed over the past 360 million years to suit different climates, soils, rainfall patterns and any niche they can fit into. This evolutionary drive often results in special adaptations – from resins and saps that deter predators or heal wounds, to attractive fruits that encourage seed distribution – the very things that make them useful to us too.
Too often trees can be seen as commonplace, a green backdrop to our lives, but they should never be taken for granted. A visit to any arboretum or botanic garden, such as the Royal Botanic Gardens, Kew, is as if you are walking through the pages of a good book that you can’t put down, with every tree a page in that book, and every page telling a different and fascinating story. In our book, we want to bring you closer to over sixty special trees, representing most of the world’s major habitats – just some of the species that could be considered remarkable. Trees have also inspired artists, explorers and botanists alike for centuries, and the book is illustrated with some of the best artworks of tree species from the library and vast collections of the Royal Botanic Gardens, Kew.
The value and importance of trees can be seen in so many ways. We build and create with an enormous variety of timbers, have discovered which parts of trees taste delicious, and which can kill or cure us, and which species add colour and spirituality to our lives. Many of these trees have changed the course of history and have added to our culture, economy and society. All have intriguing stories to tell. For instance, did you know that nutmegs were once worth more than their weight in gold? And do you know where wild frankincense trees still grow, and how this precious resin, once the world’s first Christmas present, is still harvested? Or which tree has the largest fruit in the world; which can give you a serious headache just by sitting under it; and which can kill you in three hours? The answers can be found in Remarkable Trees.
8,000 tree species are under threat of extinction and are precariously balanced in terms of survival
Symbols of stability, majesty and longevity, trees are some of the oldest, largest and most impressive living organisms on the planet and seem to exist on a different timescale from us. We will take you on a tour of some of the most remarkable tree species of the world. The yew and bristlecone pine number among the oldest known living things, while the redwoods and eucalypts tower above all other trees at record-breaking heights. Quinine, chocolate, olive and ebony are highly valued as some of the most desirable trees for their products, while others continue to be revered – including the banyan and baobab.
It is estimated that over 8,000 tree species are under threat of extinction and are precariously balanced in terms of survival. Any species becoming extinct is a tragedy as it represents the loss of an integral piece of the complex web of life in the habitat in which it has evolved. Trees help us thrive and survive, but they are also pillars of stable ecosystems and part of vast ecological networks that support many other living creatures – without trees many of them, from insects, birds and mammals to fungi and bacteria, would completely fail.
We hope this book inspires you to appreciate the wonder and importance of trees and the incredibly diverse range found around the world. In the stories revealed here it is obvious that trees enrich us, and also why we should care about them – they are an intimate part of our lives and our culture, our past and our future.
Nutmeg: Myristica fragrans
Nutmegs were once so valued that they changed the course of human history. Thousands of people lost their lives in the fight to control the nutmeg trade, and these fruits were once worth more than their weight in gold. Photo courtesy of Library, Art & Archives Collection © the Board of Trustees of the Royal Botanic Gardens, Kew
It took years of intrigue, bravery, deception and bloody war in the sixteenth and seventeenth centuries for Europeans to gain direct access to this fragrant spice. Thousands lost their lives in the fight to control its trade, and it was once worth more than its weight in gold. The aromatic spice we call nutmeg comes from the fruit, or drupe, of the evergreen tropical tree Myristica fragrans (meaning myrrh-like fragrance). A relatively large tree, reaching up to around 20 metres (66 feet) in height, Myristica is slow growing but flowers continuously and can yield up to 20,000 fruits a year. It is native to the Banda Islands in the province of Maluku, Indonesia, where it thrives in the deep moist volcanic soil of these few, small ‘Spice Islands’. Until the mid-1800s these were the only places where nutmegs were commercially grown and traded.
The fruits of the nutmeg tree develop from its tiny yellow bell-shaped flowers. Male and female flowers grow on separate trees (meaning the tree is dioecious), so both are needed for pollination to occur. The fruits that then form are rounded and pale gold in colour, resembling apricots. The outer aromatic fleshy skin is edible and can be made into jam or candied as a sweet or dessert, but it is the kernel inside that yields the spice. Ripe fruits split open to reveal the precious oval nutmeg within. Surrounding this hard brown ‘nut’ is a bright crimson lacy aril, or seed covering, from which we obtain the second spice of the nutmeg tree – mace. This is separated and dried to make that similar but more delicate flavouring. An essential oil can also be distilled from ground nutmeg, which is used today in foods, drinks, perfumery, cosmetics and in some pharmaceuticals such as cough medicines.
To Europeans in the fifteenth century the source of nutmeg was a complete mystery. It had been traded for centuries, and at the end of the thirteenth century the Italian explorer Marco Polo had described nutmegs as among the ‘surpassing wealth’ of Java. Spices were bought from merchants in Venice, who in turn had acquired them from Constantinople and a chain of other merchants stretching from the mysterious East. Wild myths grew up around its exact origin. By the sixteenth century nutmeg had become highly prized both as a food flavouring and a valued medicine and preservative. Because of its ever increasing price, many sought to find the land where the nutmeg grew. As with cinnamon, the Portuguese won the race, reaching the Banda Islands and taking over the port of Malacca in 1511. They filled two ships with nutmeg, mace and cloves, which they later sold for approximately one thousand times what they had paid the local people.
Nutmeg is being investigated for its potential medicinal properties, including possible protection against certain potent bacteria, as an aid to liver function and also an antidepressant
Nutmeg was used to treat all manner of ailments, from diarrhoea to digestive problems and more besides. When Elizabethan doctors recommended nutmeg in pomanders to ward off bubonic plague, its value rose even further and it became one of the most sought-after trading items in the world. The lure of such immense wealth drew the British into the spice trade, determined to gain their own share of the profits. In 1603 an expedition led by James Lancaster landed on the tiny island of Run (or Rhun), a small atoll 16 kilometres (10 miles) from the main Banda Islands. Here there were plentiful nutmeg trees, and after the British had made a successful first impression with the local people, trade commenced. However, the Dutch held the monopoly on spices in the region and would not tolerate rivals in this highly lucrative business. They occupied the Banda Islands by force in 1621, massacring its people and expelling survivors or selling them as slaves. They created nutmeg plantations, and in order to maintain their monopoly the Dutch East India Company destroyed any nutmeg trees not under their control. The British later ceded the island of Run to the Dutch in 1667 in return for the little-known island of Manhattan in North America. The Dutch monopoly did not survive long, however, as British explorers took nutmeg trees to Sri Lanka and other colonial tropical areas under their control. In the eighteenth century the rather aptly named French botanist Pierre Poivre made several attempts at great risk to smuggle nutmeg seeds or plants out of the Banda Islands, and finally succeeded in establishing some trees in Réunion and Mauritius in the Indian Ocean. Nutmeg-growing spread around the globe, and today the island of Grenada in the Caribbean is one of the largest producers of nutmegs in the world.
The culinary qualities and virtues of this hard-won eastern delight continue to be valued, and myriad recipes exist across several cuisines to make use of its aromatic, warming flavour. Nutmeg is also a source of minerals, B vitamins and antioxidants, and is being investigated for its potential medicinal properties, including possible protection against certain potent bacteria, as an aid to liver function and also an antidepressant. Although some people take nutmeg medicinally, excessive over-indulgence can have severe consequences including allergic reactions, hallucinations and even death, and it is also highly toxic to dogs.
The stirring tale of the nutmeg is another example of how the trade and movement of seeds around the world has affected the lives of millions and the economies of entire nations.
Japanese persimmon: Diospyros kaki
The large, tomato-like persimmons ripen in autumn to a rich, shiny orange. The leaves also colour beautifully and fall, leaving the glowing fruits hanging on the bare branches. Photo courtesy of Library, Art & Archives Collection © the Board of Trustees of the Royal Botanic Gardens, Kew
The name Diospyros is derived from the Greek words meaning divine fruit or wheat, giving some idea of the regard this tree is held in. Diospyros kaki sits in a large genus of between 500 and 700 species of deciduous and evergreen trees and shrubs, which in turn belongs to the Ebony family (Ebenaceae), which also includes ebony itself, Diospyros ebenum.
Diospyros kaki is generally known as the Japanese persimmon or kaki, hence the same specific epithet. Other common names include Chinese or Oriental persimmon. Originally native to China, where it has a history of cultivation stretching back over 2,000 years, and also Korea, it has also been grown and cherished in Japan for centuries. In the nineteenth century, it was introduced further afield, to California, Brazil and southern Europe.
In late autumn, the oval leaves of this small tree colour beautifully and then fall, leaving the large tomato-like fruits, up to 10 centimetres (4 inches) in diameter, called ‘simmons’, hanging from the branches to ripen to a rich shiny orange. In Japan the fruits are strung up after harvest and suspended on lines around the lower eaves of traditional Minka houses. They are allowed to dry naturally in the sun and then eaten as high-energy sweets called hoshigaki. In China they are peeled, air dried and squashed flat to make edible snacks or for use in cooking.
There are two main types of these edible fruits, astringent and non-astringent, which are also slightly different in shape. The astringent cultivars, known in Japan as hachiya, are more oval and pointed, and are high in proanthocyanidin tannins, which means they must be allowed to ripen fully on the tree until soft before eating or they will dry out the mouth with a single bite, never to be tried again.
Persimmons have twice as much dietary fibre as an apple, and are high in vitamins A and C, potassium, manganese, copper and phosphorus
When fully ripe, the flesh matures into a thick pulpy puree contained in a thin, shiny yellow or orange waxy skin. These are generally the kind that are used for drying. The non-astringent type, fuyu gaki, can be eaten unripe, when they are firm and crisp, or left to ripen to a jelly with a rich sweetness. So why eat an astringent persimmon? Well, when ripened it is said to have a far superior flavour to the non-astringent cultivars. In the Far East kaki can be served as a dessert after a meal, and dissecting the fruit into sections is an art form in itself.
Fresh or dried, persimmons have a soft to fibrous texture, with twice as much dietary fibre as an apple, and are high in vitamins A and C, potassium, manganese, copper and phosphorus. Like most other commercial fruits that we regularly eat today, there are now several cultivars of this exotic fruit that have been raised by growers for more flavour. Another name encountered for persimmons is ‘Sharon fruit’. This is a trade name for a type bred and cultivated commercially on the Sharon Plain in Israel, between the Samarian Hills to the east and the Mediterranean Sea to the west. These non-astringent fruit have no core, are seedless and very sweet.
Other species of Diospyros include Diospyros lotus, the date plum or Caucasian persimmon. This is the most common persimmon planted in gardens and bears the smallest fruits of the group – its common name derives from their date- or plum-like taste. It has a wide natural range and is native from the Caucasus Mountains to China and South Korea. Diospyros virginiana, the American or common persimmon grows naturally in the southeastern states of the USA up to Connecticut. It makes a tree to 20 metres (66 feet) high with deeply fissured bark resembling the skin of an alligator. The small round fruits of this persimmon are yellow, with slightly red cheeks, and are rich in vitamin C, making them popular in fruit pies; early European explorers described them as looking like a medlar (Mespilus germanica). The fruit, wood and bark were all used by Native Americans, and the dried seeds were made into buttons for the uniforms of soldiers in the American Civil War.
Remarkable Trees, by Christina Harrison and Tony Kirkham, is published by Thames & Hudson
Want more great Boundless extracts in your inbox every Sunday? Sign up to the free, weekly newsletter, here.