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More... A description is a list of the characteristics of a plant or group of plants, arranged as a series of characters, e.g. leaf blade shape, each with a character state, such as linear or lanceolate. Knowledge is required of the technical terms for the various parts of the plant, and those for the different forms that each can take. These are often difficult to understand, or can be applied in different ways. Therefore drawings, photographs and glossaries are very helpful to explain and illustrate the various parts and the terms that are applied to them. The many possible characteristics are listed and discussed under morphology. Descriptions (or a much briefer ‘diagnosis’) are first given when a species is published and named. Early descriptions were often very sketchy, and even modern descriptions vary greatly in the depth and breadth of details given. They are usually written by different people, who may have different parts of the plant to look at, or may apply terminology in different ways. Therefore scientific descriptions are eventually modified in a revision of a group of species, or in a broader regional account of plants, known as a flora. At that time the plants are compared more carefully, applying comparative tests to them all together, such as studying their anatomy, chromosomes, or nowadays their DNA. Hopefully revisions and floras should lead to improved descriptions, with the plants organized in groups that reflect natural evolutionary relationships better. Ideally the revised descriptions should have become more directly comparable to each other with time, with terminology applied more consistently and listed in a glossary, and the plants should be adequately illustrated. This may not be for a century or more after species were first described, and as so many bamboos have only been described in the last 100 years or less (fig. 1), the process of refinement of bamboo descriptions is evidently going to take a while yet. To make descriptions even more directly comparable the characteristics can be coded according to strict application of terminology and incorporated into a database, which allows identification and automatic production of descriptions. This has been undertaken for the grass species database at Kew, but the quality of the data produced depends upon the quality of the descriptions from which the data is derived. If the characteristics are only converted from author’s original descriptions, without having a revised flora account or undertaking a satisfactory revision, then there can be many problems when trying to use such data mechanically. The quality of the descriptions in a revision or flora depends upon many factors. These include how much new plant material can be examined, the geographical coverage, how well the work is funded, how much fieldwork is possible, how familiar the authors are with that group of plants, etc. Good international collaboration is often necessary, as plants do not respect international borders, and collections are usually stored in more than one country. Free exchange of plant material on loan is essential for comparison, and good access to literature is also required. This is why it is necessary to have an international network of collaborating botanical institutions, each with collections of dried or living plants, and also exchanged journals, and then rules for publishing and naming plants. Even so, several revisions usually occur over generations and even centuries before a sound and stable system of reliable names and descriptions is produced. International collaboration is usually good, with developed and developing countries exchanging specimens on loan for mutual benefit. Unfortunately in the bamboos there have been many problems in the funding of revisions, leading to superficial work or repetition of earlier, inadequate descriptions without much improvement. A great deal of detailed field and herbarium work is still required. For cultivated plants, less technical descriptions are often published in books and periodicals, along with information on their cultivation. These are usually easier to read than the scientific descriptions, and can sometimes be much better, especially as space is not such a constraint in a book as it is in a brief flora description. However, terminology may be less precise, characters used by horticulturalists for recognizing species often differ from those used by botanists, and descriptions are occasionally taken from plants grown under the wrong name. Descriptions need to be tied very accurately to a particular species name. Scientific publications always aim to be very strict in linking descriptions to the right species, using a formal system of reference to a ‘type’. This adds a whole new dimension to the business of describing plants, covered by the subject of nomenclature, which is a separate and complex area, covered in a later section of this website, which includes information on databases of bamboo names.
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