Guide To The Species Accounts

4r SCIENTIFIC NAME A species name is made up of two pans. The first part is the genus name (e.g. Ficusi comparable to a person's surname). The second part is the specific epithet (e.g. iutea; comparable to a first name). The name of subspecies or varieties {which are variants within a species) consists of the name of the species m which it is classified, followed by a word indicating its rank isubsp. or var.>t then the subspecifie or varietal epithet. For the most part we have followed the scientific names accepted by the National Herbarium in Pretoria. For reference purposes and a.s a source of historical information, scientific names are often followed by one or more personal names, sometimes abbreviated. These so-called authority citations are of link use to laypeople and I hey have been omitted in this bi>ok.

5, SYNONYMS The names under which a plant was previously known, or are alternatively referred to, are its synonyms. Many people find name changes perplexing and even downright annoying, so it is worth outlining briefly w hy plant names change, or why at any one time a species may have more than one name.

Plants often have to be reclassified following the discovery of new information. As a result, a species may be transferred from one genus to another, or a single species may be split into I wo or more species. By the same token, two or more species may be combined into a single one. or what has previously been consid ercd a subspecies or variety may be given specific rank. In certain circumstances a name may also change if an older published name ts found.

Botanists also differ in their choice of classification systems, and this sometimes means that a single species bears two or more alternative and equally valid names, each one correct within its own particular system. One classification system may, for example, emphasize the similarities between certain species and st> tend to lump them together Another may emphasize the differences between lhe same species, splitting them up into different entities. The tree Acacia albida, for instance, also bears (he name Faidherbia albida The former reflects the similarities that this species shares with the genus Acaciai the latter the differences between this species and other Acacia memberĀ».

Synonyms are preceded by an equal sign i-) and placed in brackets. In this Kn>k we supply very few synonyms and then only from I airly recent name changes. Synonyms may facilitate cross-referencing between ihis Nx>k and other publications on trees, particularly older ones. When searching the literature to find out more about a particular tree species, ytni should not only use its currently accepted correct name, but also its synonyms,

6, ALIEN SPECIES A bullet (*) preceding a name signifies an alien plant invader These are non-native plants thai have been introduced into southern Africa from other parts of the world, and which have become naturalized that is, capable of repnxlucing and spreading without human agency. Although by far the majority of tree species in southern African gardens and parks are aliens, most have not become naturali/ed and are therefore not treated in this book*

7, COMMON NAMES Common names are often confusing. The same name may apply to two or more different species, or the same species may have more than one common name. To provide a measure of stability, so-called standardized English and Afrikaans names were proposed for many native and alien trees

I Von Breitenbach 1989, 1995).

With a lew exceptions, these are the names used in this book, supplemented with a few new jy proposed imes where suitable names did not previously exist. Names in other official and regional languages have been omitted, pending further efforts towards standardization, probably and preferably by mother tongue speakers, of tree names in each particular language.

NATIONAL TRFF NUMBERS These have been proposed as a handy means of marking trees along highways and hiking trails, in nature reserves and recreation resorts, and also as a general quick-reference guide. The SA-numbers refer to those proposed for South Africa. Namibia, Botswana, Swaziland and l esotho * based on Von Breitenbach 1989, 1995). Numbers of aliens are preceded by an X. The Z-numbers refer to the equivalent ones used in Zimbabwe \based on Drummond 19K1

FLOWERING TIME In a few tree species the peak flowering time occurs withm fairly narrow limits, in many others. however, it may vary significantly from year to year over a species' distribution range, and even between two trees of the same species standing next to each other. We have therefore derided to give seasonal indicators rather than specific months. Our seasonal concepts arc intended as a rough guide only: spring = August-November; summer = November-March; autumn = March-May; winter = May-August. Fruiting logically follows directly on flowering (except in the ease ol male trees of unisexual species),

10, DESCRIPTIVE TEXT The text for each species begins with an indication of duration, habit and habitat. Duration (whether deciduous or evergreen) is very variable in some species and noi known with certainty in many others, and this aspect is not therefore described consistently. The location of vegetation types and centres of endemism mentioned in the text are shown in the maps on pages X and M, Salient features of the bark, branchlets, leaves, inflorescence, flowers and fruit are then described. Particularly significant diagnostic characters are primed in bold, These characters, in combination, arc normally essential for the positive identification of a species Although we have tried to use language ihat can be readily understood by the lay person, some botanical terminology has been unavoidable {see Glossary, page 516),

1 L PLANT USAGE Trees are not. of course, significant only for their place in the natural order and for the grace and beauty they bring to the land. They have immense practical value as food, medicine, Uxrfs, furniture. building materials, shelter and fuel. Selective mention ts made of specific uses lor some ot the species. This feature has often had to be kepi very short, or even omitted altogether, because of space constraints. Many of the healing properties ascribed to tree parts have not yet been scientifically proven, nor have any potentially negative side-effects been established. We have therefore refrained from mentioning specific medicinal usages, unless ihese have been validated by research.

\2. RELATED SPECIES Where appropriate, (he names of closely related species and their diagnostic characters are provided. The diagnostic characters ol easilj confused species are also given,

13. DISTRIBUTION MAPS Each species exhibits a certain pattern ol distribution, which is one aspect of its definition The distribution maps are compiled on a range style: the shaded areas are presented as a rough guide to the geographical limits of a particular species. The perimeter of a species distribution is approximate and, indeed, somewhat arbitrary. It does not indicate specific localities, nor does it give any indication whether a species is evenly spread over the area or occurs only in isolated localities. I he colour of the shading will tell you whether a species is endemic - that is. restricted - to southern Africa (green), native to the region but also found further north in Africa (orangey or a naturalized alien (blue).

14. COLOUR PHOTOGRAPHS Each species description is accompanied, on the lacing page, by one or more photographs. Thus all pertinent information relating to a tree appears on one spread. Illustrations showing features that are particularly helpful in identification (flowers, fruit* vegetative characteristics) have been selected. Growth forms and bark patterns have been included only if these are especially diagnostic.

15. CAP f IONS Isabel captions give the scientific name for the species, and the part(s) illustrated.

Its, ENTRY NUMBERS The number adjacent to each species entry corresponds with the number of the species illustrations) on the opposite page.

17. RUNNING HEADS These itemize the family or families that feature on ihe left hand (text) page, and (he group into which they fall.

18. THUMB INDEXES The colour of these corresponds with the colour of the relevant group panel appearing in the Key to the Groups (pages J6-I8) and in the Ouick Guide on the inside back cover

KEY TO THE GROUPS - Diagram A

Ptiinh with teave* jnd/or Mein* mjuliICIH

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