Plant Renaming

Botanical names can change and evolve over time. The main reason for a change is due to a taxonomic reclassification where the plant is considered (at the time) to be more appropriately located elsewhere.

One example that can be used to show how a plant has been reclassified since it was originally credited to Carl Linnaeus as being the first person to describe it as Couch Grass.

Common Couch grass
1: Triticum repens L.
2: Agropyron repens (L.) Beauv.
3: Elymus repens (L.) Gould
4: It has also been classified as Elytrigia repens (L.) Desv. ex Nevski, but the current name used in the UK is Elymus repens (L.) Gould (See Clive Stace (2019) 'New Flora of the British Isles', 4th Edn).

Authors
a: L. = Carl Linnaeus (other spellings are: Carl von Linné, Carolus Linnaeus), Swedish botanist, 1707 - 1778
b: Beauv. = Ambroise Marie Francois Josep Palisot de Beauvois, French botanist, 1752 - 1820
c: Gould = Frank Watton Gould, US botanist, 1913 - 1981
d: Desv. = Nicaise Augustin Desvaux, French botanist, 1784 - 1856
e: Nevski = Sergei Arsenjevic Nevski, Russian botanist, 1908 - 1938.

Reclassification sequence
This plant was reclassified into a different genus in accordance with Beauvois's suggestion, then placed into another after Gould; lately it was reclassified in some systems according to earlier suggestions of Desvaux and Nevski. However, within the UK Couch grass is currently classified as Elymus repens, unless it is considered to be more suited to another genus, in which case it would be reclassified again.