There are nearly 700 characters presented in an organised way. To make this easier, the Expert also includes an extensive help system, and a Library of queries already listed that answer common questions. Great care has been taken to include plants from right across Australia. In future versions of REX, it is intended to add more plants, and to add plants from particular areas eg rainforests, rangelands. Although there are more WA plants in the database than from other States, this accurately reflects the relatively large number of plants used from Western Australia.
Trees are the image for rural revegetation, and shrubs attract the attention of gardeners.
REX has tried to expand interest in different growth forms by including plants from trees to grasses and ferns. Many understorey plants are in the shrubs and smaller plants in the REX database. Several relevant plant characters include values in nature habitat, wildlife food supply, and nesting habitats. For some plants, there is more information available because they have been widely used and recognised. REX builds pages on each plant that only presents the fields with known information.