Keys

Artificial analytical constructs for identifying plants.

The identification, nomenclature, and classification of plants are the domain of plant taxonomy, and one basic responsibility of taxonomists is determining if the plant at hand is identical to a known plant.

• The dichotomous key provides a shortcut for identifying plants that eliminates searching through numerous descriptions to find one that fits the unknown plant.
  
  
• A key consists of series of pairs (couplets) of contradictory statements (leads). Each statement of a couplet must “lead” to another couplet or to a plant name. Each couplet provides an either-or proposition wherein the user must accept one lead as including the unknown plant in question and must simultaneously reject the opposing lead. The user then proceeds from acceptable lead to acceptable lead of successive couplets until a name for the unknown plant is obtained. For confirmation, the newly identified plant should then be compared with other known specimens or with detailed descriptions of that species.
  
  
• Keys are included in monographic or revisionary treatments of groups of plants, most often for a genus or family. Books containing extended keys, coupled with detailed descriptions of each kind of plant (taxon), for a given geographic region are called manuals or floras, though the latter technically refers to a simple listing of names of plants for a given region.
  
  

• Key to New Mexico Penstemons ... Read More

• Revised Penstemon Key of the Great BasinClick here to read or download this key, new from Noel Holmgren June2008. Based on Volume IV of Intermountain Flora of 1986

• Key to the Penstemons of the Siskiyou Mountains by Ginny Maffitt