Tree is used for values that can take on items from hierarchical lists. A good example is Country and City lists. Every Country has a particular set of Cities, so we can say that Cities list is hierarchically subordinated to Countries list. There is no restriction in the number of levels for a field of tree type. For example, you can add third level to the Country/City field for the list of suburbs of each City.

To modify a field of tree type, click edit icon near the field of the 'Tree' type. A tree field modification page will be opened. Enter level IDs and level captions divided by commas in the appropriate fields and click the 'Save' button. To edit values of 'Tree' type, click 'Edit Tree Values' on the edit field info page. To add a new item to the 'Root' items of the tree field, input it into the 'Value' field in the 'Add a New Tree Value' dialog box. To add or edit values to the 'Root' items, first choose the parent item from the list of existing items and click the edit icon. On the 'Edit Tree' page you will see the list of values for the chosen parent item. On this page you can edit tree value, add a new tree value, change the order in the list of existing items, edit existing items or delete them. To import data from .csv or .exl files, click the 'Import data from file' link on the 'Edit Tree' page. 'Import Tree Data' form will be opened. Choose the file you wish to import using 'Browse' button. Choose the format of your file. Enter line from which you want to import data to the 'Start Line' field and click 'Import' button.

By default, fields of this type display as select boxes for each level on the input and search forms.