Identification Tips

 
1. Become familiar with the specimen
2. Choose the appropriate characters
3. When you have addressed all the obvious characters …
4. Always skip a character that you are unsure about
5. When selecting states, if you are uncertain of the correct choice
6. If you end up with no taxa remaining
7. Do not assume that you will end up with a single taxon remaining
8. Once you have a potential target taxon, check the associated information

This is a short 'best practice' guide to allow you to make the most of the advantages and flexibility of AusGrass and of the Lucid software under which the interactive key runs. Of course, no two identifications will be the same, and you will need to be flexible in your approach. However, taking note of the suggestions below may help, especially if you are new to Lucid or other interactive keys.

This section is especially important if you are familiar with using printed identification keys in books, but are new to interactive keys. AusGrass gives you the choice of using either a dichotomous key (which is essentially the 3rd edition of Bryan Simon's A key to Australian grasses, a popular printed key) or a Lucid interactive key. An interactive key like AusGrass works in some ways like a printed key but in other ways is quite different. Lucid keys are a type of interactive multi-access key (also called a random-access key). While the questions (couplets) of a printed key need to be answered in a fixed order, in Lucid you can address any character at any time. One of the big advantages of this is that you need not get 'stuck' by being faced with a question that you cannot answer – if this happens, simply find a question that you can answer. It is important to use this feature, and not to dwell overlong on a character that is difficult to answer.

This raises another important advantage of a random-access key. There is no need to have a complete specimen to be able to identify it using the AusGrass interactive key. Of course, the more complete your specimen, the more likely you are to be able to identify it quickly and accurately. The vegetative characters of grasses are notoriously 'plastic', so identification may not be possible without flowering material.

You will usually find it useful to proceed with an identification using the following steps.

1. Become familiar with the specimen.

Briefly reviewing the characteristics of your specimen before you start will make it easier as you proceed through the identification. Also, some plants possess unusual or distinctive features – using these may enable the specimen to be keyed out in very few steps. As you become increasingly familiar with the grasses you will come to know many of the characters, and you will know where to find them in the key.

2. Choose the appropriate characters.

Not all characters in AusGrass have equal discriminating power – some are better than others, depending upon where you are in the identification process. Therefore, choosing the appropriate character is important in getting you most quickly to the 'right' answer. The problem is, of course, that unless you are familiar with the grasses it is often difficult to know what characters are appropriate to use in particular circumstances. Fortunately there is some assistance available to you in this regard. When you first start AusGrass you will see 23 (Best and Simplest) characters listed in Characters Available. These characters are generally easy to score and have been selected for their strong discriminating power under most circumstances. By answering as many of these questions as you can you will normally reduce the list in Taxa Remaining markedly. For further assistance on character selection see Which characters should you use?.

3. When you have addressed all the obvious characters, ask Lucid to suggest the best remaining character.

The Best menu option will cause Lucid to assess which of the remaining characters will best reduce the list in Taxa Remaining. Using one or other of these Best characters would give you the most efficient next step. When using AusGrass it is sensible to run Best using the All set of characters after you have answered as many questions as you can on the default Best and Simplest character set. You do not have to use the first character suggested by Best, look through the list till you find one you are comfortable answering.

4. Always skip a character that you are unsure about.

The easiest way to go astray with an identification is to guess at a character that you are unsure about, either because you don't understand the character or because the character is not clear on the specimen. One of the great advantages of an interactive key is the ability to skip characters – use this feature. Also, become familiar with the notes which are provided to help you understand characters and character-states.

5. When selecting states, always choose multiple states if you are uncertain of the correct choice.

Lucid allows you to choose multiple states from one character. These states will be connected with an or link, and Lucid will search for all taxa with state A or state B. If you are unsure which of two or more states your specimen has, then choose them all. That way, you can be sure that your target species will remain in Taxa Remaining. (Note, however, that choosing all the states of a character is equivalent to not choosing the character at all, since no taxa would be removed from Taxa Remaining.)

6. If you end up with no taxa remaining, review your chosen character-states and delete any that you are dubious about.

An empty Taxa Remaining list means that no taxon in AusGrass matches the selection of character-states that you have made. This may be because you have found a new species, or because we have made an error in coding the data. However, it is most likely that you have made a mistake in one or more characters. If you are dubious about any of your choices try deleting the states that you are unsure about to see what effect it has. One or more taxa may move back into Taxa Remaining. In difficult cases, you may need to 'play' with the key, adding or deleting character-states progressively to try and find the best matching taxon.

7. Do not assume that you will end up with a single taxon remaining.

Some taxa are very hard to differentiate, except by using difficult or obscure characters. Even after you have addressed all the characters that you can, you may still have a short list of taxa remaining instead of just one. If this happens you may be able to proceed further by reading the description that is provided for each taxon, or by scrolling through the drawings of them. You may also be able to proceed with the dichotomous keys provided as part of the AusGrass package.

8. Once you have a potential target taxon (or small group of taxa), check the associated information to see if it matches.

Getting a possible name of a taxon from AusGrass is not the end of an identification. You may have made errors, or you may have a species that is not in the key. In these cases, the key may have provided you with the wrong name. Always check the accessory information for the taxon (or taxa), namely, the descriptions and images.

As this is the first release of this package and the data has not been completely checked for accuracy the possibility exists for some of the data to be incorrect. Therefore feedback to the compilers of this key will be appreciated where data errors are suspected to occur.

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