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Taxonomy
An Introduction to Botanical Names.

Introduction

A tree may have a number of different common names to describe it. It may be known in America by one name, in England by another and in Wales by yet another. An example of such a situation is Acer pseudoplatanus where in England it is called the Sycamore but was once called the Great Maple, in America it is known as the European Sycamore or the Sycamore Maple while in Scotland its called the Plane. To make matters more confusing the name Sycamore actually means Fig-Mulberry and in America the Eastern Plane is know as the Sycamore.

Such confusion needed to be removed if scientists and botanists were to communicate and share information on a particular species. A universal system of species identification was needed, a system that would use a single name statement and be applicable in all countries around the world.

It is essential to notice and prune out such branches if you wish to retain the variegated foliage of the cultivar. If you do not, the parental foliage will quickly outpace the growth of the variegated foliage and subsequently produce a normal green Norway Maple (this is happening to the tree located in the background, this tree will soon revert completely and is probably now not restorable through pruning).

History

Prior to the 17th century, all living things were identified by a long descriptive sentence. As the number of discovered species increased, such a method of reference must have proved very difficult to use. It was at this time that Caspar Bauhin devised a method of assigning two names (binomial) to each species and then in the early 18th century Carl von Linne (Linnaeus) established the system further and undertook the task of actually naming all the living species.

The Binomial system

This system uses a system where 2 names are used to identify living things. Each name consists of 2 main parts. The first part is called the generic or group name. This would be likened to our surname. An example of such a generic name would be Quercus which represents the group of Oak trees. There are many different species of Oak trees so a further means of separating these was required. The second part of the botanical name represents the species, so our common English Oak is now classified as Quercus rober. Our second most common Oak, the Sessile Oak, is classified as Quercus petraea. The Cork Oak, common in Spain and Portugal but also found in the U.K is a major source of cork and is classified as Quercus suber. The generic name always begins with a capital letter while the species name does not.

E.g Pinus nigra

Sometimes trees of a particular species evolve naturally to produce slightly different characteristics from the majority. As an example, this may occur due to the containment of a group of trees where perhaps topographical conditions have isolated the group to the point where these trees are continually pollinating each other and do not receive pollen from trees further away. This 'inbreeding process' may produce changes in parts of the tree, perhaps as a different colour foliage, habit or leaf shape. If such evolution of a species continues it may be that the tree evolves sufficiently to warrant a completely new species name. Trees discovered with significant changes from the normal species are termed as a variety of the species and will require the addition of an extra name to separate these trees from the original species. The name of the variety is stated after the species name and indicated with the abbreviation var (they do not begin with a capital letter).

E.g. Pinus nigra var.maritima

Trees can also be propagated by planting cuttings or by grafting cuttings onto a parent root stock. As an example, a tree may have a branch that exhibits a slightly different colour foliage than the rest of the plant. Cuttings are taken from this branch and planted to produce new trees which may grow on to have a whole crown showing this new colour. Although these new trees look different they are in fact clones of the original tree so keep the same species name. They are not called varieties but instead termed cultivars or cultivated varieties. This name follows the species name and is enclosed in single quotes and begins with a capital letter. An alternative method of presenting the cultivar name is to write it without quotes but with the abbreviation for cultivated variety cv.

E.g. Fagus sylvatica 'Purpurea' or Fagus sylvatica cv. Purpurea

This concludes my brief guide to plant name structure. There is more to learn, such as authors names, hybrids and plant classification. The late Alan Mitchell describes the whole subject briefly in the introduction of his book, Trees of Britain & Northern Europe.

Further Information

Book. An Introduction to Plant Taxonomy by C. Jeffery.

Book. Trees of Britain & Northern Europe by A. Mitchell.

Book. Plant Names Simplified by A.T. Johnson and H.A. Smith.

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