# Adding PFTs, Species, and Cultivars

Plant functional types (PFTs) are used to group plants for statistical modeling and analysis. PFTs are associated with both a specific set of priors, and a subset species for which the traits and yields data will be queried. In many cases, it is appropriate to use default PFTs (e.g. `tempdecid` is temperate deciduous trees)

In other cases, it is necessary to define PFTs for a specific project. For example, to query a specific set of priors or a subset of a species, a new PFT may be defined. For example, Xiaohui Feng defined PFTs for the species found at the EBI Farm prairie. Such project-specific PFTs can be defined as `` `projectname`.`pft` `` (i.e. `ebifarm.c4grass` instead of `c4grass`).

Species that are found or cultivated in the United States should be in the Plants table. Look it up there first.

To add a new Cultivar, go to the [new cultivar](https://www.betydb.org/cultivars/new) page: `Cultivar` → `new`.

![](https://3274248152-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LAygTHTsiUBYNnv4HkC%2F-LAygY-Zj6iF0qOparCb%2F-LAygcdUK2JeckTY_slf%2FAddnewcultivar.jpg?generation=1524691538224129\&alt=media)