Therophyte

Therophyte is a category of Raunkiær's system. It refers to plants of which only the seeds last in the unfavorable season. The term is composed of etymus whose origin is the Greek terms θερος (théros), summer, and φυτών (phytón), plant.

Due to their size, therophytes are classified into macrotherophytes and nanotherophytes. They are also distinguished by the period of the year in which they vegetate: winter therophytes (for example, Senecio vulgaris or Phaseolus vulgaris), and summer (Amaranthus deflexus) .

Therophytes are common in desert climates and Mediterranean climates, with mild winters and dry summers, during which absolute vegetative rest can be an advantage. They are also frequent in ruderal environments (road edges, suburban waste dumps, etc.) which are unstable environments, in which it is an advantage not to build long-lasting vegetative apparatus. On the contrary, in the high mountains therophytes are very rare, since their populations need to produce seeds and new plants every year to perpetuate themselves, and it is likely that a particularly rigorous year will prevent the flowering or germination of a species, which would mean his disappearance from the place.