Ask Mr. Smarty Plants

Your points are well-taken.  We do not willfully exclude Mexico in our databases, although it may seem that we do.  In fact, that we don't include more information about Mexican native plants species in our databases is a source of great frustration for us.  The absence of information on our website about Mexican native plant species is a function of two factors. 

First, for technical reasons only those species that have been assigned a plant code by USDA Plants can be included in our databases (e.g. LUTE is the plant code for Lupinus texensis (Texas bluebonnet)).  The USDA plant codes are at the heart of our databases.  Since many Mexican species have not yet been assigned a USDA plant code, we cannot yet include them in our databases.  One seemingly obvious solution, to simply assign our own codes to Mexican species, would be a workable short-term solution, but would result in chaos in our databases at a later date when USDA does get around to assigning their own plant codes to them.

The second factor, is simply the lack of detailed information about Mexican native plant species.  Researchers, including some at the University of Texas, are currently working hard to catalog and describe all of the Mexican plant species, but much of that work is yet to be published.  Where we do have information and a USDA plant code for a species native to Mexico, we include it in our databases.  Future upgrades of the NPIN databases will include much more information and functionality for Mexican native plant species.

Regarding the second part of your question, we believe that the most appropriate plants for Austin, Texas are those that are native to Austin, Texas, whether or not they also happen to be native to northern Mexico, Seattle, Vermont or anywhere else.  That is the essence of our message; try to use plants native to your own area - whatever that area is - when landscaping.  Our databases includes information about plants native to Seattle, Vermont and the Rocky Mountain region, as a resource for people living in those areas and also for people interested in the plants of those areas.