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Dynamic computer formats will probably revolutionize field guides by making the access of information more user friendly and more flexible, even if the guide is
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ultimately to be printed for field use. Sites on the internet or databases on a CD-ROM will increasingly produce guides customizable for species and geographical coverage. You can prepare for this now by collecting digital imagery and defining character databases as a prelude even for a book project, and maintaining your data and documents in as logical a format as possible.
The potential for non-computer, yet dynamic, field guides
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A printed (or printable) modular guide project (see Box 5.12) could provide a platform whereby sponsors pay per species and see them used variously in different environments; independent workers collaborate to contribute to a wide field guide effort; and users from many backgrounds can take their results and adapt them to their own need. Identification would be based largely on browsing, facilitated by a structure put into place by the consortium, and this would be useful for facilitating the international aspects of such projects.
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Modular guides and other dynamic formats can be updated without a major revision.
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Dynamic, unusual formats (like punched hole cards) often attract more interest among students whose botanical interest has yet to be turned on than, say, a static format book because they are interactive and different. As novelties, they may be more sellable than standard books. For an eco-tourist venue, think up educational games that could be built around them.
Static formats: Classic field guides are still the best option for field users
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Do not underestimate the value of a basic indented dichotomous key and crisp black text on white paper as a good access method. While they are not the most fashionable, such keys represent the clearest and an efficient way of displaying textual information for a decision tree. Multi-access keys are useful, but often over-rated: certain characters will have to be observed, anyway, if a plant is to be identified, so there is no harm in steering all users through the easiest and most reliable of these questions first, and little advantage to allowing users to avoid answering them early on in their decision-making process, as is advocated for multi-access keys.
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Books or laminated cards are mostly more practical for fieldwork in tropical forests than dynamic formats. When computers are involved with dynamic formats, the hardware may end up being less convenient, portable or affordable than a basic book. Personal digital assistants (PDAs) are not yet powerful enough (in 2006) to substitute.
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Books do not need technical support and are ‘future proof’. Computers consume bench space and require air conditioning and a reliable and protected power supply.
They are likely to be hijacked for other uses.
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Book users need less training than computer users, especially if they are not comfortable with computers. The layout of a book is globally well understood.
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The more familiar printed medium suits the purpose of many authors adequately, earns more academic credit and works during power cuts. Dynamic formats are currently harder to publish for scientific citation. If you are a scientist or are working with one, their future employment may well depend upon the production
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of easily peer-reviewed publications in a static format. This will presumably change as more information is published electronically.
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In educational terms, the lack of a rigid structure engendered by dynamic formats might make learning of the plant groups harder. Some e-keys allow characters to be prioritized for ease of use, or reliability, even though users can choose to ignore the recommended next best question. If one encourages complete flexibility of identification path, the benefits associated with learning a taxonomic structure, or at least memorizing where certain types of species are to be found in a field guide, will be reduced.
•
More information is needed for a complete data matrix for an interactive key than for a static dichotomous key, as all possible routes to an answer have to be planned for; yet, not all character states are even worth codifying for all species, and missing field data is normal for rare species, but can usually be steered round in a static key.
Dynamic keys often therefore involve more unnecessary work and non-botanical skills to produce than static guides.
•
E-keys often (allow authors to) rank the best characters to use, including those with multiple states. Because the author will not, in general, know the context that the character will appear in, nor the other species that will be possibilities when the question is to be addressed, this can be harder to optimize than with a static key.
•
There is a danger that machine-customized field guides look somewhat uninspiring, like automated catalogues. Designers of static guides can tweak the format to suit the species and users.
CONCLUSIONS
Interactive guides or keys have several major advantages over conventional guides; but they are not replacements: at the moment they cannot easily be taken into the field and more people potentially have access to books than computers. However, with the software available it is possible to produce an interactive guide as a secondary output with little overhead when the primary output is a published guide in book form. Why not create both a static and dynamic field guide (for example, a CD-ROM or website accompanying a book)? A realistic target for a computer guide that helps field botany is to support the use of field and sterile characters for identifying specimens. But beware –
there is a danger that the computer component of the work will consume disproportion-ate resources.
Modular guides and structured browsing can work well, and have other advantages for managers of field guide projects, and especially sponsors seeking efficient solutions for plant identification in the tropics.
Facilitate browsing for and within groups of distinctive species; but if parts of your guide deal with difficult species, list characters and make a key for them. Keys are difficult to plan for in modular guides; so it might be best if one key to all species is made for all species of a difficult genus in the modular guide, and the local implementers of the modules are helped to create keys to the fewer local species.
For difficult groups, dichotomous keys work well – and well-planned indented keys are clearer than numbered ones. Ask your users what they think, after some practice.
You may be able to devise simple multi-access tables if the defining characters are
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simple; but they are not necessarily any easier to use or more efficient than dichotomous ones, however succinct and satisfying they are to the guide authors. Test your key with a sample of the users (Chapter 9), before finalizing it, to be sure.
Do not expect to necessarily be able to model your guide on expert skills; but by all means see what range of characteristics various experts look at, smell or taste in their own identification. Go hunting for characters both in the field and in the herbarium that no one before you has found, to make your access methods as foolproof as possible. It is these characters that are covered in Chapter 6.
6
Plant characters suitable for field guides
William Hawthorne
INTRODUCTION
Plant characters were introduced in Chapter 5 as the foundation of botanical identification. In this chapter we focus on field characters that tend to be most useful in tropical forest field guides. But due to limited space, the chapter can only be an aperitif: many more topics, specific examples and details are explained on our linked website (see Box 1.1). Just a few common sample cases are included, biased strongly towards woody plants that dominate rainforests; but the principles and tips for field guide writers that these illustrate are gene
rally applicable (see Box 6.1) Field characters are generally less well understood, with less standardized terminology, than the classical fertile or anatomical characters that form the backbone of most other botanical publications; but there is no shortage of relevant jargon. Out of the jungle of myriad structures and terms, you have to find a set that are understandable and observable by your prospective users, and that are, at the same time, useful from a diagnostic point of view. In some cases, you will have few decisions to make, especially when dealing with distinctive groups – grasses, palms, bamboos, mistletoes, orchids and so on – for which monographs highlight the useful and often rather unusual or specialized field characters you need to know. For instance, for cacti, you will probably refer to size and shape of the plant, spines and stem ridges, no matter what form your guide takes. In other cases, including most woody rainforest plants, you have more choice of characters to focus on.
Classical characters can certainly not be ignored when considering the preparation of a field guide; but there is no need to cover them all here. Just read the glossary of your local Flora or botanical website. Stearn (1966), Harris and Harris (1994) and others in the References section have provided well-illustrated glossaries for classic characters (see Box 6.2).
Beyond the essential words for your own field guide, it is important to understand jargon in order to make good use of botanical literature, and to understand where published information is compromised due to lack of clear standards about its meaning.
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BOX 6.1 FIELD CHARACTERS AND CLASSICAL CHARACTERS
A field character is one that is useful for identifying a plant living in nature without special equipment (hand lens, bush knife, binoculars, catapults and other field equipment excepted), in all seasons and potentially for plants of any age. Some field characters are also useful for identifying sterile herbarium specimens.
The classical school botany lexicon – from Abaxial to Zygomorphic – represents the basics of the scientific tradition of botany, but is far from ideal as your only source of characters for field guides. It is the language that describes the characters used by taxonomists, anatomists, morphologists and other indoor botanists: characters we call ‘classical’
here to contrast with the field characters on which field guide writers have to concentrate.
As we pointed out in Chapter 4, most plant names are defined with respect to classical characters of pressed, dried herbarium specimens – usually seasonal details of flowers and fruit – and this bias diffuses into Floras and other botanical literature; but field guide writers should not follow the trend uncritically.
There is considerable overlap between field and classical characters and no possibility of dividing them into two exclusive sets. Some characters – for example, leaf type and arrangement – are useful in all circumstances. However, the emphasis with respect to how these ever-useful characters are described depends upon where they are to be used. For instance, it is reasonable to provide greater detail on leaf venation in a field guide than in a Flora because for fieldwork it is more likely that a sterile plant will have to be identified.
Flower details in a field guide might focus more on the superficial characters, such as colour and size of the whole flower, whereas the Flora might concentrate on numbers of stamens or ovules and other ‘deep’, but more obscure, characters with a more fundamental and global significance.
BOX 6.2 AN UNFORTUNATE DIVERSITY OF JARGON FOR
CLASSICAL CHARACTERS
Even 40 years ago, you could have filled a small library with literature whose sole purpose was to define words for biologists. The Systematics Association (1960) made a list of about 350 ‘authoritative’ publications of this type. The choice is bewildering; but the situation is particularly difficult for field characters of tropical plants, which tend to have been dealt with less meticulously than classical characters. A major problem is that glossaries of botanical terms frequently contradict each other or exclude some vital, modern standards of botanical description, even where the standards do exist. For example, there has been an attempt to make words used by botanists for outline shapes (such as leaf or petal shape) more precise by defining ratios of length/breadth for each term (Systematics Association, 1962); but these are missing from widely used glossaries by Harris and Harris (2000), Bell (1991) and several others published or re-edited since the standards were set, and many writers use the terms with their older, imprecise meanings (see also Jackson, 1928).
Be circumspect and critical of others’ choices of terminology, and define with your users the jargon to use in your field guide without confusing the standard terms that are well accepted (see Box 6.2, and see Chapter 3 for methods).
Plant characters suitable for field guides 123
BOX 6.3 OTHER REVIEWS OF FIELD CHARACTERS FOR
TROPICAL FORESTS
There are a few previous overviews of a wide range of useful field characters for tropical plants. Rosayro (1953) discussed field characters for tropical tree identification, for instance, and Wyatt-Smith (1954) also tried to standardize terms for Malayan trees.
Letouzey (1986) has reviewed more classical characters, albeit in a user-friendly way: these and similar treatments border on generic or family field guides, discussed in Chapter 4. In fact, for many purposes, the best general reviews are in the introductions or glossaries of actual field guides.
Keller’s (1996) book on vegetative characters is one of the very few general overviews that even attempts fully to review tropical forest field characters, alongside many characters that are of little use in the field but which enable plants to be identified without flowers and fruits. Perhaps rather ambitiously, Keller’s book is, in part, a key to tropical plant families or other large groups. It makes few concessions to amateurs, using a full gamut of jargon, albeit mostly well illustrated, and requiring microscopic or careful analysis of detail.
But this is still an interesting and original vegetative guide to plant family identification. For certain field characters, particularly tree architectural models, it provides a useful illustrated reference, and writers of technical field guides will benefit by trying to work through the keys with proposed guide users, if only to show which types of character are practical. The 1996 edition is very far from complete with respect to tropical plant families; but hopefully it represents a work in progress.
Similarly highly detailed, almost encyclopaedic, but not always practical or complete sources for field characters are Metcalfe and Chalk’s botanical classic (1979, and other editions and volumes, especially volume 1), Metcalfe (1988) and Keating et al (2003, likewise in several volumes).
Because many standard botanical works, and certainly original species descriptions, underplay field characters, field guide writers should discover and publicize, rather than simply précis, published information.
The following section and the associated web page (http://herbaria.plants.ox.ac.uk/
VFH) will help you to decide which jargon to use and to make definitions in a working glossary for your own purposes. Find out if your prospective users understand these terms after an acceptable learning period. Your glossary should be one of the first products of your field guide project (after the species checklist) and distributed to co-authors as a list of allowed jargon. Make your definitions precise enough, with copious illustrations so that you and your co-writers and readers can follow it strictly. You may, however, need to refine it as your research progresses.
Jargon: When ‘pyriform’ goes ‘pear-shaped’
It is tempting for the radical field guide writer to avoid all jargon as it can be off-putting to casual users and students:
•
Translate jargon: field guide writers are the interface between the public and acade-mia. They are therefore more obliged than other botanists to translate jargon to normal language wherever appropriate; but also to educate readers where necessary.
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&nb
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Some jargon can be substituted with illustrations (for example, of shapes), a good reason to make profuse use of illustrations. The conciseness afforded by specialist words is of no benefit if those words also put users off using the field guide.
•
Some jargon terms are hardly necessary in any type of botanical literature, let alone a user-friendly field guide.
However, while not all botanical terms will be appropriate in your field guide, many unfamiliar words that are not often heard on the high street will have a useful role. Like scientific nomenclature (see Chapter 4), one of the advantages of jargon over common language is that jargon words can be given very specific fixed meanings by scientists and others who depend upon precision – for instance, apiculate is more precise than pointed, and tomentose or puberulous are more specific terms for hairy. Learn to judge when hairy suffices, or perhaps when tomentose increases the fitness of your guide for its purpose. However much you like plain words, surely you wouldn’t think of removing
‘tree buttressed’ in favour of ‘tree non-cylindrical at base, with triangular outgrowths supporting the tree’ throughout your guide? Some jargon is almost indispensable for keeping your field guide short and light – and the weight of a field guide book is likely to be a major design constraint.
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‘Good’ jargon is concise and highlights the crucial features in a description, forming a simpler mental picture and therefore making the point stand out, much as a diagram does in the pictorial world.
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Even if you are illustrating profusely, you may have to explain certain points with words. For instance, in an ‘incomplete set’ guide (see Chapter 4), you may want to explain in a footnote, without a picture, how a rare plant differs from the common one illustrated. Rarely encountered species may justify usage of unfamiliar terminology.
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