Open the program by clicking on the KEY TO SPECIES button or double-clicking on the Intkey icon  .


The top row of icons (outlined in red below) give you general options.



 Clicking on the book icon gives a table of contents with the following links: About CD (brief information); General Information (detailed information about CD and general arctic botany); Using the key (instructions on how to use this program); Accessing Descriptions (instructions on how to access the descriptions and illustrations without keying out the species); Hints on Using Intkey (with reference to the DELTA help page); Implicit characters (default character states); Acknowledgments; Bibliography (all references in the text plus additional sources of information); Contacts (contact information as of 2007).


 "Include accepted species and subspecific taxa" button reduces the number of taxa listed in the right-hand window to those that occur in the Canadian Arctic Archipelago for which data are available that would allow identification, i.e, species, subspecies, and varieties. The program opens with these taxa chosen as default.


 ”Include all the taxa” button. This taxon set also includes more inclusive taxa such as families and genera. Keying is usually not done with this setting because some taxa do not have data for keying and others are inclusive of taxa below so that keying will not lead to a single taxon.


  “Display character and taxon numbers“ button on the tool bar turns on numbers beside both the list of characters and taxa, which may be useful for finding a particular character or taxon (to turn numbers off, click File>Advanced mode / Settings>Display>Numbering>Off. To return to Normal Mode, click File>Normal Mode).


  “Help” button on extreme right-hand side. For more help press this button and then any active button.





We will key out a plant found in the Arctic and also further south: Fireweed (Chamerion angustifolium).



Use the left-hand window for keying. In the window is a list of “Best/Available Characters.” The program defaults to showing the characters in the best order to separate the taxa in the database. Since we have flowers, we can start with “stamens (number).” If you had only fruit, you could start with choosing “fruit (type).”  NOTE: If a different character appears than the one you chose, this is a dependent character. You will need to answer an initial more general question (usually related to whether the feature is present) before you will be allowed to answer the question that YOU have asked about the feature.




If you have any uncertainty about the definition of a character, click on Notes. Notes contains definitions and other information about characters and their states. Otherwise, enter the number of stamens (8 in this case) and press OK.



The next list will have the available characters listed in order to best separate the remaining taxa (listed on the right). Since the plant has bright pinkish petals, we can pick “petals (colour)” next.



Since it is difficult to tell whether the petals are pink or purple we can choose both states by clicking on the picture or the state. The character state box will turn black when the state is selected. Press OK.




After choosing petal length 20 mm and aerial stems erect, you will come to the following window:



Double-click on the species name or click on the information icon   to get the Taxon Information window. Click on the Help button for more information on checking identifications. If you need to correct a character state, click on the character in the Used Characters box and a window will appear to allow you to change the value.




Double-click on Full description to show the text describing the species. If no information is given when a heading is clicked (e.g., indigenous knowledge), this means it is not available. Double click on an illustration to bring up an illustration. For example, “Close-up of inflorescence” brings up the following photo and caption:



Our picture matches our plant, so the identification is successful.

Scroll down the list of illustrations. The map is always at the end. To see all the available illustrations as thumbnails, click on the “multiple images” button at the bottom. Each thumbnail image can be maximized, reduced, and closed using the Windows toolbar. Note that double-clicking on an image will also close the image window. To close all windows go to the main toolbar, select Window, and click on “close all.”




Information on additional buttons in the Character-Taxon toolbar


*  The “find text in characters” button allows you to search for a character instead of relying on the “Best Characters.” Click on the binoculars icon in the left-hand window, and enter the name or part of the name you seek. Click "find" and the relevant information is highlighted in blue. The window also gives the number of hits. You may choose to do this if your plant has a striking character such as obvious stolons or if the characters at the top of the “Best Characters” list are not available or easily observed.




    The “restart identification” button prepares the program for a new identification.


*        The “best order” button is on by default. The characters are presented in the ”best order,” that is, the character that best divides the database into nearly equal portions is presented at the top of the available characters window.


    The “natural order” button arranges the characters in the available characters window in the order in which they appear in plant descriptions, starting with the nomenclature, then roots, stems, leaves, flowers, fruit.


   The “set error tolerance” button allows one to increase the “error tolerance” for an identification. The default value is zero. Clicking on it gives the option of increasing the “error tolerance”, which allows a defined number of mismatches (1, 2, 3..) before taxa are eliminated. This can be helpful if you are unsure about scoring certain characters or believe you have made a mistake in identification.


   The “use a subset of characters” button gives access to a list of character sets (e.g. leaves, petals), mostly related to plant parts. Click this button and then a keyword relating to the kind of character you wish to focus on (e.g., petals).


   The “differences between taxa” button. Highlight two or more taxa of interest, then click on this icon. A window opens with a list of the characters in which the taxa differ.


  The “use a subset of the taxa” button allows one to focus on a smaller group of plants (e.g., ferns, grasses) for identification. Highlight the names of the taxa in the subset of choice, e.g. all the Equisetum taxa. A window appears. In this window choose “selected” to reduce the number of taxa to those selected, then continue keying.





Advanced Mode is used for more sophisticated interactive identifications. The program opens in Normal Mode. To go to advanced mode choose “File“ in the toolbar and highlight the option “Advanced mode.” Many more options for approaching an identification appear. Decimal numbers that appear at the left-hand side of the character list when “best order” is chosen indicate how good each character is at separating among the remaining taxa. The “best order” uses these numbers plus character reliability values incorporated in the data.


Information on these commands can be found under Help > Commands, and more detailed information on them is available in the User’s Guide to Intkey (Dallwitz, Paine and Zurcher 2000), available at the Delta home page under the heading User Guides).


Additional buttons


  “Separate a given taxon” button. Highlight a species, then click on this button to cause the characters to be ordered in the best order for separating that species from all others.


  “Set match” button. See below under Toolbar: Settings.



Toolbar: Queries


Describe This is used to compare the character states present in a limited number of taxa. For example, highlight the species of Equisetum. Click on “selected“ to choose just these taxa. If you know that these taxa differ in characters relating to the “aerial stems“ choose that character, click OK, and a list giving the characters of the aerial stems of the selected taxa appears. The data is presented in order of taxon.


Differences This is a useful option to use during the identification process. It streamlines the information given to the characters in which the taxa differ. It is presented in order of character followed by the information on this character for various taxa. It is often most useful in focussing on characters useful in an identification. e.g.,


40. Aerial stem ridges

3. Equisetum arvense


5. Equisetum scirpoides


6. Equisetum variegatum


41. Aerial stem ridges

3. Equisetum arvense

 (2) the same number as that of the leaf teeth at each node

5. Equisetum scirpoides

 (1) twice as many ridges as there are leaf teeth

6. Equisetum variegatum

 (2) the same number as that of the leaf teeth at each node


Toolbar: Browsing

Characters This option gives the same information as the  “use a subset of the characters” button.

Taxa The window that opens allows for selecting all, remaining, or accepted species or subspecific taxa.

Find  This command is similar to pressing the binocular button, to find either characters or taxa. The output is more detailed, and includes common names and nomenclature.

Information  This is another way of accessing the information that is readily available from the information  button.



Toolbar Settings

For the purposes of doing identifications a useful option under this heading is


Set and the option Match =  “Set Match” button





“Match” compares how the data recorded for a taxon “matches” a character. The data may be “inapplicable” (the plant is a grass and does not have conventional petals), “unknown” (not recorded or implicit for that taxon), or recorded as “overlapping” in one of more states of a character (for example petal colour might be recorded as white or yellow).




The window opens with the options highlighted:  “inapplicables,” “unknowns,” and “overlap”

When these options are highlighted, any taxa to which these “match“ options apply for a character remain in the list of taxa available for an identification.


For example:

If the character “petals (colour)“ is used and “yellow“ is selected with the above match setting 84 taxa remain listed in the taxon window.

If “Match“ is set as exact, only the taxa that have been recorded as being yellow only are listed in the taxon window, and the number is reduced to 49 species.

Not Enough Characters to Complete an Identification

In some circumstances, there may be insufficient characters for identification. For example, if your specimen is incomplete, there may be no characters that separate the remaining taxa, but there may be other reasons why an identification is not successful.

(1) The specimen information that you have entered may be too broad. You can find out which characters separate the remaining taxa by selecting all the remaining taxa, and pressing the “differences“ button in the “taxa“ toolbar.

(2) Characters that are generally considered inappropriate for use in identification (for example, number of chromosomes) have set “reliabilities“ set to zero. This prevents the characters from appearing in the “Best Characters“ pane. You can find out whether such characters separate the remaining taxa by selecting all the remaining taxa, and pressing the “differences“ button in the “taxa“ toolbar. If a useful character is found, you can access it by first pressing the “natural order“ button in the “characters“ toolbar.

(3) It may be that the taxa really cannot be separated by the comparative information in the database. Information in the “taxon information” window (accessed by selecting/highlighting a taxon and either clicking  or double-clicking on the taxon name). The information may include explanatory supplementary information and/or references in the discussions in addition to the comparative information from the database.


Do you want to add the data set you have just used to the index?

If you have copied the CD to your computer, you will be asked this question. Answer “yes” and click OK, which will add a small file index.ind that will prevent this question from appearing again. You may also answer “no”; if you answer no, this question will appear every time you use the program on your hard drive.