Ask Mr. Smarty Plants

Mr. Smarty Plants visited the Texas-North Central Recommended page to find only Echinacea angustifolia (Black sampson) and Echinacea purpurea (Eastern purple coneflower) listed.  E. purpurea has both "Eastern purple coneflower" and "purple coneflower" listed as its common names.  Echinacea pallida (Pale purple coneflower) also has another common name listed—"pale coneflower", but E. pallida isn't on the Texas-North Central Recommended list.  So, I'm not exactly sure what you are asking.  Are you asking if we have the wrong common name associated with E. purpurea?  Should "purple coneflower" be used as the common name for E. pallida?  If that is what you are asking, there is an authority that dictates what the appropriate scientific/botanical/Latin names should be—the International Code of Botanical Nomenclature is the authority that sets the rules—but, for common names there is no authority.  The common names are determined by people who live in the region where the plants grow.  If the plant occurs over a large region, it's almost guaranteed to have more than one common name, especially if the language of the regions are different (e.g., Pluchea odorata (Saltmarsh fleabane or sweetscent) has the common name of "Santa Maria" in Mexico but its botanical name is Pluchea odorata everywhere).  To complicate things even more, common names can refer to two (or even more) totally different plants.  An example for this is Smilax pumila (Sarsaparilla vine) which also has the common names of "wild sarsaparilla," "dwarf Smilax," and "dwarf greenbrier."  This plant is in the Family Liliaceae (Lily Family).  Not only is Aralia nudicaulis (Wild sarsaparilla), which shares the same common name as Smilax pumila, a completely different plant, it is even in a completely different family—the Family Araliaceae (Ginseng Family).  So, if you are asking if we have given the common name "purple coneflower" to the wrong plant, who can really say for sure?   Some people may call E. pallida "purple coneflower" while others call E. purpurea by that name.

Now, it is possible that you are asking if E. pallida should be on the Texas-North Central Recommended list instead of E. purpurea.  You can see by the Texas distribution maps from the USDA Plants Database for each (E. pallida and E. purpurea) that neither is widely distributed over North Central Texas.  E. pallida does have a slightly larger distribution, but they have both been cultivated and grow well there.  According to Joe Marcus, at the Wildflower Center:

"The lists were compiled of native plant species that are both native to a given area and can be found in the nursery trade.  So while Echinacea pallida is known to occur in North Texas, the list compilers could find no nurseries in that area that offered it for sale."

This, no doubt, is why they included E. purpurea and E. angustifolia, but not E. pallida.

Finally, if you are questioning the fact that there are two common names by E. purpurea, then I will point out that many of the plants on the list have multiple names.  For instance, E. angustifolia (Black Sampson) is also called "Black Samson echinacea" and "Narrow-leaf Coneflower."