•
A chapter or section on ‘How to identify plants in the field’: this covers what to look for and particular features that might be confusing. Also include a section on ‘What to take with you to the field’. This section will depend upon the existing knowledge of the target audience.
•
The key characteristics of the plant group covered by the guide, as well as main diagnostic characters: for example, the team producing the guide to legumes of the Caatinga in Bahia, Brazil (de Queiroz et al, forthcoming) debated, at length, the value of including a section on ‘How to identify a legume’. In the end, the team chose to include a section on ‘Easily confused species’.
•
An introduction designed to inform the reader, whet their appetite and encourage them to use the guide: this chapter will depend greatly upon your users and their level of interest and formal education, their occupations and their reasons for using the guide. As indicated in Chapter 2, for example, eco-tourists are likely to take the most interest in the general features of the area or plant group included in the book, and to enjoy reading about the history of ecological change, conservation and use of the plants. Others will be interested to know the relevance of local knowledge and plant use for conservation, or to read about the organizations involved in producing the guide.
Testing
All of the descriptions, introductory/explanatory text and layout of the text will be based on specifications prepared at the design stage, using the guidelines in Chapter 3. However, it is still necessary to check that the results are correct, understandable and useful. Every stage must be tested: analysed and formatted information must be cross-checked with the original sources of the information; and the language, style and layout must be checked with the potential users. Ultimately, it is important to be clear about roles – who owns the guide and who makes the final decision about what is correct or acceptable. In Bolivia, for example, the scientific authors of the guide to the useful plants of Bajo Paragua (Vargas and Jordán, 2003) saw themselves as the technical team who oriented, supported and
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collected information, and analysed and presented results back to the communities. The ultimate decisions about content and format were made by the indigenous community members.
Chapter 9 provides guidance on testing the content, layout and usability of your guide.
8
Illustration
William Hawthorne and Rosemary Wise
INTRODUCTION
In earlier chapters, we saw how illustrations reduce the need for jargon, and work where literacy is limited or the audience speaks various languages. They facilitate a browsing approach to identification, which can be at least a useful starting point for identifying plants, and can show where details fit in the context of the plant as a whole in ways that words alone cannot. Even where the users think they know the plants, images are useful to confirm identification and for drawing attention to differences that might not otherwise be noticed. All users strongly prefer field guides that are illustrated and might not even try to use guides without them. They usually make the guide more attractive, more useful and likely to be used.
Illustration of one form or another is therefore likely to be essential in your field guide; yet the preparation of illustrations may well be your major task. In this chapter we summarize the pros and cons of various types of illustration, making frequent reference to trials on the subject in Cameroon, Ghana and Grenada (see Case study 8.1). We assume that anyone who is preparing a million-dollar field guide will have the services and advice of a professional photographer or illustrator; so on the basis of this, we are targeting our advice at projects with a more modest budget.
As with all aspects of the guide, the decision about what kinds of illustrations to use will be based on informed knowledge of, or consultation with, the user (see Chapter 3) and tested (see Chapter 9) before final publication.
THE CONTENT OF A PICTURE: SOME GENERAL PRINCIPLES
The choice of the characteristics of a plant to illustrate should be obvious from our earlier discussion of characters (see Chapter 6) and your own calculations and consultations on what it will take to make the guide work (see Chapter 3). Clearly, some important characters, such as smells, cannot easily be illustrated (‘scratch ’n’ sniff’ type patches being too unrealistic, unsubtle and short-lived); but the need for other characters
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CASE STUDY 8.1 DFID–FRP (PROJECT R7367) TRIALS OF
ILLUSTRATIVE MATERIAL IN FIELD GUIDES
William Hawthorne, S. Cable (Plant Sciences, Oxford), R. Lysinge, E. Njenje (Limbe Botanic Gardens, Cameroon), M. Abu Juam, N. Gyakari (Forestry Department, Ghana), D. Jules (Forestry Department, Grenada) In the UK Department for International Development (DFID)–Forestry Research Programme (FRP) Field Guide Project, we evaluated graphical aspects of field guide formats, based directly on empirical trials in Cameroon, Ghana, Grenada and Oxford. The full details and results will be published elsewhere (see Box 5.7, page 100, and http://herbaria.
plants.ox.ac.uk/VFH for an update on this publication). Briefly, workshops were held to discuss the needs, formats and styles of field guides, and a set of species and image formats were chosen for trial. In each country, 20 to 150 species were selected and a series of comparable ‘guidelets’ made for them. A guidelet is a set of pages or cards with features of a field guide to be investigated by practical field trials (in reality, we would expect many field guides to have more species; but a subset of 20 to 100 species for browsing should be easily filtered by major divisions in a guide). More than one format of guidelet was made for each species to allow the effect of format to be evaluated in a standardized way. We tested guidelets for accuracy (percentage correct in a trial, usually of 20 plants in the field); and we recorded the respondents’ subjectively assessed confidence of answers, usability, beauty and monetary value. Around 1500 respondents and about 30,000 plant person-guidelet events were evaluated. We also compared these attributes in two types of trial.
Most were ‘name that plant’ trials, where users were asked to match a numbered tree to a species in a guidelet. We also conducted species recognition trials, to test whether a picture reliably brings the correct species to mind or could be used to communicate to respondents which type of tree they were to find in a patch of forest.
In Cameroon, at Limbe and around Mount Cameroon, we tested eight formats of guidelet for 19 species of Cola (small trees, many rare or economically important) (see Figure 8.1 and Plate 6, centre pages). Respondents only knew of the species earlier in less than 10 per cent of cases. The formats, from photocopies, dried specimens, drawings and photographs of various types, made little difference to the accuracy – which was generally poor (40–60 per cent) for this difficult genus.
In Ghana we tested one modular format of the guidelet to 125 large tree species in two sizes (see Figure 8.2), mostly with villagers around forests. Prior knowledge was minimal; but after using the guide, accuracy increased to an average of about 80 per cent.
In Grenada, we tested card guidelets in shuffled packs of around 20, containing equal numbers of paintings, drawings and photographs (see Figure 8.3). Each species was in the respondent’s hand only once, in one of the formats. Again, prior knowledge of plants was low. Here we found significant differences in overall accuracy between habitats (averages from 60 per cent for montane forest to 80 per cent in other vegetation types). The slight differences in format were insignificant.
In all test sites, photographs were overall the most successful, with some gain in subjective scores or accuracy for different formats in different subsamples.
The full results are published elsewhere (see Hawthorne et al, 2005, and http://herbaria.plants.ox.ac.uk/VFH for publication details).
Illustration 185
Source: S. Cable, R. Wise & W. D.
Hawthorne
Figure 8.1 Sample guidelet
pages from the formats
tested in the DFID–FRP
Field Guide Project for
Cameroonian Cola
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Note: see Plate 7 for the colour component of each card.
Source: W. D. Hawthorne & R. Wise
Figure 8.2 Sample guidelet pages (A5 or A6) tested in the DFID–FRP
Field Guide Project for Ghanaian large trees
Illustration 187
Note: see Plate 8 for optional colour cards these were compared with.
Source: R. Wise & W. D. Hawthorne
Figure 8.3 Sample guidelets (A6 cards) with drawings of Grenadian plants, tested in the DFID–FRP project
188 Plant Identification
will help to determine the medium of illustration that you need. For instance, a guide to large trees based on slash colour and texture has to be based on colour photographs. If geographical distributions are to be highlighted, then perhaps include maps among your illustrations. We will not discuss mapping further; but you should probably make them directly with a computer geographical information system (GIS), the subject of a whole shelf of books on its own. Some principles of information content are independent of the subject matter, though, including picture scale, arrangement, detail and copyright.
Scale
Many users who are not used to viewing printed images have a problem interpreting scale and perspective. Even for experienced users, illustrators should plan for an appropriate way of helping the eye understand that a picture is a close-up view or far away (see Box 8.1).
In general, we recommend that you select a standard set of different sizes of scale objects for all of your images; scale objects should be of simple shape, recognizable by all your users. Hands, fingers and whole people, with or without added precise sizes, are a reasonable general scale solution, although pure centimetre markers might be better in guides intended for technical users.
Arrangement
You may sometimes want to include all characteristics of a species in one illustration, or you may prefer to separate out particular details, such as pods or seeds, on a special plate for comparison. This task becomes easier with digital imagery, and inappropriate or difficult if you have chosen to use real specimens or photocopies or photographs of them. One of the advantages of an artist’s input to your project is that they will probably have an eye trained to arrange images on a page in an aesthetically pleasing way.
Although we are inclined to idealize plant parts when they are illustrated, it can be more useful to show them as they are usually seen. For instance, leaves of some species are almost always riddled with holes, eaten at the tip or margin.
Detail
Although you may be inclined to make your illustrations with as much detail as possible, too much detail becomes confusing, and the less complicated your images are the easier it becomes to browse many of them quickly:
•
In many cases, silhouettes (see Figure 8.4) may be as useful as more detailed photographs. They can easily be made in many ways.
•
The addition of highly detailed X-ray pictures of venation patterns did not significantly improve the accuracy of identification with line drawings in Limbe, Cameroon (see Case study 8.1).
•
Details are usually best added to drawings in ‘detail boxes’ (or in circles, representing the view through a hand lens). These are easily implemented for digital photographs and enable you to use a low-resolution version of a photograph, with an inset of, for example, part of the venation, with higher resolution. This can be emulated easily on photographs; but it may be clearer to include a second
Illustration 189
BOX 8.1 DEPICTING SCALE
There are six main options for representing scale:
1
Show all at life size. This is appropriate for less experienced users where appreciation of scale depicted by any means fails, and where you have decided it is possible to make the guide work on items such as leaves or parts of leaves. This will seriously limit your choice of subject matter and prevent depiction of detail, but is inevitable if you are using real plant specimens in lieu of illustrations and a reasonable solution if you are using photocopies of specimens. It should be emphasized that people who have never seen photographs can have a very difficult time coming to terms with scale even with very strong visual clues such as elephants and Acacia trees.
2
Show images at various scales and rely on background clues in each to make scale obvious. If you use a black cloth as a background, the weave of the cloth can provide some scale clues for close-up photographs. We can intuitively tell that a photograph of a whole tree on the edge of a forest is not life sized because we have never met trees and forest-like objects that are only a few centimetres tall, and there may be clouds in the sky anyway. The flattening out of shadows or lighting associated with photographs of leaf surface details also seem obviously not to relate to, say, a football pitch-sized area. A mass of yellow flowers on a street tree might be so distinctive that the precise length is not important anyway. In these ways, it may be possible for some images to work without adding explicit scale information. This option seems to apply especially to photographs; similar visual clues are generally missing from drawings.
3
Magnification factor: some technical images have a ‘x 10’ or ’life size’ caption, to inform the users of the scale. We advise against these (unless all pictures are life size) because they become complicated if images are reproduced at different scales – for example, with a photocopier – and because they can be hard to understand anyway.
4
Include a scale bar. A small 1cm line is the standard practice on many technical drawings. These are generally better than the previous type as they are still correct when images are reproduced at different sizes. However, many non-technical users may not be familiar with centimetres or inches.
5
Include a scale object in your pictures. You can substitute for clues that might be naturally present by adding your own. This is standard practice in some photographs, where coins, for instance, are often used. We advise against lens caps (which vary in size and are unfamiliar to many); but matchboxes, biros (especially Bic biros), pencils, disposable cigarette lighters and paperclips are well known to many. Parts of the body such as hands, feet and whole people are useful since they are generally available to the photographer, although this is not much use where a precise scale is needed. For close-up photographs, however, the hand or clutching fingers are useful inclusions as you probably need to hold the specimen still anyway. These can also work well for drawings. Rosemary Wise’s drawings in the field guide to Ghanaian trees and African Acacia (Hawthorne, 1990) use cartoon people to help scale large trees, and pencils in diagrams of leaves.
6
The world’s pencils or people are of very roughly the same magnitude, yet variable in precise size; their usage as a scale object therefore sends the message that the true size of the plant part depicted is approximate due to natural variation. But the pencil or other scale object can still have a precise length or width written where this is important – that is, scale objects can be left as imprecise sizes if the subject of the image is variable in size anyway, or have added dimensions written where the precise length is critical.
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Note: Some compound leaves are complicated and the jargon is mostly unspecific regarding how lobing merges gradually into separate leaflets (2–3 pinnate, with deeply toothed lobes), so it is often better to avoid the jargon and use pictures or icons. These images were made in 45 minutes by scanning a fresh leaf, cleaning up the background, increasing the contrast to make the image more diagram like and reducing the resolution (with edge smoothing).
Source: William Hawthorne
Figure 8.4 Leaf silhouettes created using a scanner photograph (zoomed in) showing the details, with the location of the details indi
cated on the first, especially if the photographs are printed in small sizes (< 4cm across).
Copyright: What can you ‘borrow’ from other artists?
Of course, one of the easiest ways to illustrate your book might be to copy images from Floras, monographs, or the internet. However, under the Berne Convention (see Box 8.2), you can only copy images 50 years after the artist has died, although most countries have extended this term to 70 years. This does mean that you can, in principle, scan and use without permission 19th-century and earlier drawings, although you will probably need to obtain permission from the library where you have found this material, in case there may be more specific restrictions.
It is always advisable to obtain permission to use material found on websites, even if the image seems to be public domain; often, the web artist will be happy for you to do so in exchange for some acknowledgement, particularly if your rendition is a lower resolution version of an original anyway. Ask the publishers and editors of Floras in your area for their opinion on this (liability for getting copyright clearance lies with the author, not the publisher or the person who gave permission to use the work).
Illustration 191
BOX 8.2 COPYRIGHT ISSUES
The Berne Convention is an international copyright treaty signed by 160 countries. The regulations of the Berne Convention are more far-reaching than, for example, US copyright law. The convention requires member states to recognize the moral rights of integrity and attribution. Authors or artists have exclusive rights to translate, reproduce, perform or adapt protected work. As soon as a creation appears in some tangible form (that is, not just an idea expressed in a conversation), it is protected. No notice (for example, the © symbol) is necessary, although it helps legal cases. The correct form for the notice is ‘Copyright
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