Plant Identification
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For the neotropics there is Gentry’s A Field Guide to the Families and Genera of Woody Plants of Northwest South America (1993), which very successfully breaks the ice for a biodiverse area at a mostly generic level, without getting bogged down in all species-level details.
Although bordering on the latter type, we exclude from our definition of field guide the following types of more academic book. There are family-level treatments where one or two genera or species are given as examples, to be used in university or secondary school systematics classrooms or field trips in conjunction with specimens carefully selected by a teacher. In addition, there are keys and other guides to the families of vascular plants that cover all of the tropical regions, but which require fertile material and the dissection of flowers to succeed. Finally, there are many other student texts ranging from simple (such as Heywood, 1993) to the more academic (Geesink et al, 1981). Keller (1996) is considered in Chapter 7.
Case study 4.4). Different versions are also produced by the UK Field Studies Council; fold-out cards, each on one theme, are aimed at schoolchildren (see, for example, Edmonson, 1997).
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Another approach is to produce one card per species, such as the 67-species guide to aquatic plants, held together with a metal post, by Ramey (1995). This type of format apparently has untapped potential for biodiversity problems for reasons outlined in the discussions of modular guides in Chapter 5.
A set of laminated cards covering the same species as a typical field guide need be no different in information content. Card guides are a relatively new innovation; but since their main innovation is in the access method, we discuss these further in Chapter 5.
Electronic guides
Electronic media are fundamentally and positively affecting the manner of publication of some botanical information, both in terms of interactive internet guides, including self-assembly field guides that can be printed for field use based on the species and information you want in your guide, and applications with multi-access keys, potentially self-published on the internet. Again, because the new spirit of these guides is in the access method rather than information content, we discuss them in Chapter 5.
Plant names and botanical publication 87
BOX 4.13 FIELD GUIDES TO INCOMPLETE SETS OF SPECIES
‘Incomplete set’ implies that not all of the plants defined by observable characteristics in the title are included. A Field Guide to the Medicinal Shrubs of Java would probably be an incomplete set as a field guide because ‘medicinal’ is not something that you can usually observe on a plant, and not all shrubs are included. Most, if not all, field guides to functional groups such as ‘medicinal’, ‘timber trees’, ‘poisonous’, ‘edible’ or ‘useful’ and certainly ‘rare’ plants are incomplete sets, as were the old herbals.
Field guides written for incomplete sets (see the section on ‘Listing the species according to subjective criteria’ in Chapter 3) present special problems if identification has to be conclusive in the field, although a high proportion of the potentially eligible plants in the field are ignored in the guide:
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If your guide is to an incomplete set, ensure that either identification from scratch is not important or, if it is, enough information is included to distinguish confusable species missing from the book from those illustrated and described within it. Otherwise, users will find plants in the field that are not in the book but look like ones that are, and then tend to assume the name of the similar species is correct. There is a strong tendency for this type of mistake, especially when users keen for an answer do not realize how similar related plants can be. This problem may be made worse because common names are quite often the same for similar species.
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If verification of names is important, rather than identification from scratch, then obviously the local name indexing will have to be researched and implemented fully.
You will still need to be aware of the confusable species and make clear how to distinguish them.
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Try to include pictures and diagnostic text to help distinguish the included species from all the most similar ones in your area, including those that are otherwise missing from the book.
YOUR FIELD GUIDE WITHIN THE SPECTRUM OF TYPES
Your choice of guide format involves choosing an access method, format and arrangement of the information in your guide, as well as the type of information. At this stage, you may already be in a better position at least to choose the broad type of field guide you want to make, and this will determine some of its features. You might find it helpful to think about and discuss this polarity as an early step in designing your field guide, not forgetting the vast range of possibilities in the spectrum between the extremes:
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Do you need a ‘shallow guide’ – a short-term, attractive guide to stimulate interest, to be a souvenir to sell for profit, or to draw eco-tourists to an area? These are cheap and relatively easy to plan and make, and can often be designed as a fold-out pamphlet or card rather than a bound book. Simple ones, perhaps with 20 to 50 of the most glamorous species, can be planned and made in under three person months.
However, they will probably not help serious biodiversity assessment greatly, or facilitate many other benefits from the plant community, or do much to stimulate botanical knowledge of the area. These are the fast food of the field guide world, designed for rapid consumption, on a modest budget, with less attention to the long-
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CASE STUDY 4.4 CHICAGO FIELD MUSEUM RAPID COLOUR GUIDES
Robin Foster with Corine Vriesendorp, Chicago Field Museum The Rapid Field Guides initiative is a desktop operation run by four people part time and is subsidized by grants. A few thousand people have obtained copies. The main focus is Latin American students. We sell many at neotropical congresses, at the equivalent of US$1.50 or US$2 per laminated sheet, depending upon the country. This covers the cost of materials, which at one point we calculated to be US$1.35 per sheet, but certainly doesn’t cover labour and shipping. When I make trips to these countries I usually carry a suitcase full and give them to an outlet (for example, the Herbario Nacional in Ecuador), and they sell them with proceeds going to a student research fund. Since we don’t make any money, there is no profit to give to the outside authors. Although I’ve told them they could have 100
copies free and they can sell them if they want, there has been no expression of any interest in making money from this.
So far, even though I’ve hawked them door to door at bookstores in Quito, and tourist outlets for the Machu Picchu guides in Cusco, there hasn’t been any response, even though at the latter they said they could sell them for US$10 each and I was willing to provide them at US$3 each. I might have to have an agent in each place. I am looking into having them printed in-country; but getting the printer cartridges for these inkjets is a problem. If one had real commercial potential, maybe we could afford to do runs of a thousand or more on higher-end commercial machines. There are some 130+ guides with 700+ pages available, and I would guess maybe 8000–10,000 species pictured. If I have the pictures ready with the appropriate dimensions and size, and I know the flora pretty well or have a list given to me, I can certainly do a one-page guide in a couple of hours, a 40-page guide in maybe a week. And we can print and laminate a few hundred pages in a day.
But there are all these other variables, especially with outside authors, in getting the images ready and identified: getting the images to Chicago; scanning slides, negatives, or prints, or adjusting pre-scanned or digital camera images; data-basing the images, etc.
Photoshop improvements are usually less than a minute per image. Checking names can slow things down (for example, Cubans are often using many plant names that haven’t been updated since the 1950s). I am getting a backlog of guides to be produced. If I dedicated my time to it, I guess I could do 100 or more different guides in a year, which averages s
omething like two per week.
term nutrition or development of the mind. They can still benefit biodiversity through publicity and livelihood creation. There are several possible themes for such guides, and there are few universal recommendations beyond what we have said in Chapter 3. It is often only important to make your guide as attractive and stylish as possible.
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Do you need a deeper, more technical guide, such as the pragmatic or tree Floras or field monographs? You do if accuracy is really important and a proper understanding of at least part of the flora is highly desirable. Either the regional Flora is too hard to use or is impractical. Or there is no usable Flora because it is incomplete, decades out of date or non-existent. Such a guide is harder to justify on short-term economic grounds, unless subsidized by a development agency or implicitly subsidized in terms of the time for which you and your collaborators are already supported. Here are some related issues for technical guides:
Plant names and botanical publication 89
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With a technical guide, think long-term education, not only short-term identification. Design your guide to stimulate learning, not only as an identification aid.
This is easy to forget when testing drafts. Do not expect that users will immediately pick it up and identify all species accurately on day one; but it is important that they are at least intrigued.
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Do not underestimate the time and communication that will be involved in getting the nomenclature sorted out and in integrating your guide with the long tradition of botanical literature for your region. The more out of date or out of range the nearest Flora is, the greater this element of your team’s task will be; 100 to 200 species per author year might be a reasonable estimate.
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Do you need something in between the simplest and the most technical – perhaps guides that help people to ensure that they are talking about the right species before using, eating or cultivating it, without drowning them in too much spurious information? Or do you need a sophisticated tourist guide? These may be biodiversity guides with an eye on identification or confirmation of identity; or they may be dedicated identification guides with corners cut to broaden the audience. These are neither very technical (because of the audience) nor superficial (because they need to be accurate with respect to some of the information at least). As with all compromises, the results in terms of accuracy, economics and so on may well fall between those outlined for the first two options:
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These intermediates are the guides where the decisions on accuracy, coverage, usability and price will tend to involve compromise, and where your users’
detailed advice on information content and format is so critical, perhaps much more so than in the more technical guides (where fundamental rules of science will limit choices) and in simpler guides (where the whole guide will be much simpler anyway and a book designer might have the most to say).
Better than choosing one or other of these options, why not choose more than one?
Make the most of the potential synergy between different types of guides, between short-and long-term benefit.
In other words, diversify rather than compromise in your guide production plans.
Here are some examples:
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Produce small, local, cheap ‘shallow’ colour guides based on your more technical one. Having prepared all of your illustrations, corrected all your names and so on, why not publicize the bigger project by producing shallow guides almost as advertisements? Make posters for schools; postcards, with the book title on the back; booklets for sale to tourists; mini-guides to difficult or important groups; and/or trail guides to small areas, all capitalizing on the same set of information and materials. Perhaps one commercial output could subsidize a longer-term one. Cheaper educational guides with fewer species, showing the important principles of plant identification or introducing users to the commoner plants, might encourage some students to grow into a full user of your larger technical field guide.
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In some highly seasonal vegetation, where there are many visitors all year round, you may consider a dry season guide to trees based on bark and flowers, and a wet season one based on leaves.
90 Plant Identification
BOX 4.14 LEUCAENA GENETIC RESOURCES HANDBOOK
Colin Hughes
It is relatively easy to justify spending resources on specialist identification tools – including field guides – for groups of small numbers of species in economically important plant groups (for example, eucalypts, pines and forage legumes), particularly for difficult groups and groups with high species diversity in a small area. Specific identification tools for species of a single genus – Leucaena – are justified by wide cultivation, breeding programmes and environmental impacts that involve several species and artificial or spontaneous hybrids. Many cases of previous misidentification in these arenas have hindered forestry or agroforestry practice and research.
Having previously prepared a taxonomic monograph on the genus over many years, The Genus Leucaena : A Genetic Resources Handbook was made for more practical users (Hughes 1998a, 1998b). Identification is dealt with in Chapter 5 of the handbook.
Identification tools include a morphological glossary, spot identification characters, composite plates illustrating character variation (leaflets, glands, pods, flowers and bark), a tabular summary and a dichotomous key. With hindsight, I can see many ways of improving the user friendliness of the chapter – for example, by including all species in all composite plates comparing flowers/glands/pods, etc., rather than just illustrative of overall diversity; standardizing species order in these plates; and better cross-referencing and navigation aids for the different options within the chapter.
Full drawings of all species to allow verification of identifications are included in the same handbook. I used a combination of photos and line drawings. Line drawings from the monograph were easy to reformat for identification. Taking more photos in the field would have been advantageous.
‘Hiding’ the identification chapter within the larger book has pros and cons. Many potential users, and even readers, do not realize it is there. Many people wanting to identify Leucaena species might not think to look there. A stand-alone identification guide would make the task easier. Limited distribution and availability of the handbook (1200 English and 350 Spanish copies have been distributed/sold and are now essentially gone) is a problem.
A web version is planned that seems likely to be much more accessible, useful and permanent. I am also considering a Lucid-style e-key on the web as a better alternative.
For the taxonomic monographer, production of a variety of more user-friendly identification tools is straightforward, easy, quick and incurs minimal extra cost – one week for a group of this size. This is because the author knows the plants well and because of the availability of illustrations. However, assembling all of the other information (on uses, silvi-culture, ethnobotany, seed storage and pretreatments, as well as conservation) was much more time consuming and entailed approximately six months of work.
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If you have used a database to keep track of details of your species, or you have developed a digital picture library, consider using this database to make a web- or CD-based interactive guide. A website of your field guide can only increase your catchment of interested plant identifiers, provide a site for corrections, perhaps for a subsequent edition, and increase awareness of the plants or forest of your interest.
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Annotated checklists might provide an interim and publishable target output for a project. ‘Modular guides’, which we discuss further in Chapter 5, also offer a steady trickle of outputs rather than waiting for one end product.
5
Identification:
Keys and other access methods
William Hawthorne
INTRODUCTION
Plant identification is the process of estab
lishing a recognized name for a particular plant or specimen. Ruling out the ‘ask someone else’, and potential automated methods such as DNA barcoding (see Box 5.1), there are two paths or methods to identification in terms of how we think:
1 identification through recognition apparently involves the instantaneous, (‘holistic’
or ‘gestalt’) appreciation of many parts of the plant at once; 2 identification through analysis is the rule-based method, involving a conscious sequence of considerations about individual characteristics, or ‘characters’.
BOX 5.1 AUTOMATIC IDENTIFICATION
Automated methods for plant identification have been discussed seriously for a decade or more, although they have had virtually no impact yet on fieldwork and still remain a topic for research. The currently fashionable topic is that of DNA barcoding, whereby small fragments of DNA of existing species would be sampled and registered on a DNA barcode database. Identification would then involve rapid sequencing of DNA from unidentified plants, an increasingly cheap and rapid process although not yet very field friendly. This approach has apparently more chance of providing a realistic tool for automated identification in the next decade than those that attempt to analyse plant morphology, such as leaf shape (see Box 6.7, page 133). The internet has many references to these cutting edge topics, new ones appearing regularly – for example, see the BioNET archive on computer-aided taxonomy (www.bionet-intl.org/) for references on these and many relevant subjects.
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BOX 5.2 DO YOU KNOW HOW YOU RECOGNIZE COMMON OBJECTS?
Consider how you identify your close relatives or friends. You probably recognize them without consciously thinking how. If you had to write a field guide with which others could identify them, you would have to think about what features characterize each of them.
Experts – such as scientists, farmers or herbalists – recognize their plants apparently with just a moment’s thought; but learners usually have to struggle with rules and conscious attempts to memorize facts. Confronted by a plant at the limits of their expertise, experts are like learners and have to think more analytically: ‘It can’t be A because it’s in a swamp, so it must be B.’