Historically, plant suitability has been defined in qualitative terms like drought tolerant, acid tolerant, disease resistant, etc. To more accurately determine what plants are sited to what areas, quantitative tolerances must be defined (how much water is needed, how low a pH can be tolerated, what temperature minimum can be survived, etc.). This section provides information on what factors are important, how the quantitative characteristics have been defined, and what values have been assigned to the species contained in our database.

Please note, this is an iterative process. Factors will be revised, added, and delted as more knowledge is gained. Quantitative values will be refined as new data is provided and as maps are revised according to expert local knowledge.

If you'd like to help with the process, please contact us at webmaster@forages.oregonstate.edu