Botanical NomenclatureBotanical Nomenclature

Plants may have many common Plants may have many common namesnames

Plants have only one scientific namePlants have only one scientific name Scientific names are universally Scientific names are universally

acceptedaccepted

Binomial System of Binomial System of ClassificationClassification

Invented by the Swedish naturalist Linnaeus in the year 1753

The genus comes first and is always capitalized and italicized

The specific epithet comes after the genus and is always lower case and italicized

The SpeciesThe Species The genus and specific epithet

together form the “binomial” that identifies a species

Example: Cercis canadensis Eastern Redbud

A group of individual plants that have a common set of identifiable characteristics that are inheritable

Species come “true-to-type” from seed

The VarietyThe Variety A group of plants subordinate to the

species; differing from the species in one or more inheritable characteristics

Varieties come “true-to-type” from seed Written in lower case and italicized Two acceptable formats:

Cercis canadensis var. alba or Cercis canadensis alba

The VarietyThe Variety

Cercis canadensis Cercis canadensis var. alba

The CultivarThe Cultivar In ornamental horticulture cultivar

characteristics are, generally speaking, not inheritable

Cultivars, generally speaking, do not come “true-to-type” from seed

Cultivar names are always capitalized and written in single quotations

Example: Cercis canadensis ‘Forest Pansy’has maroon leaves that fade to green

The CultivarThe Cultivar

A single species may have many cultivarsJuniperus horizontalis ‘Blue Chip’Juniperus horizontalis ‘Plumosa’Juniperus horizontalis ‘Hughes’ etc.

It is possible to have a cultivar of a varietyGleditsia triacanthos inermis ‘Skyline’ orCornus florida rubra ‘Cherokee Chief’

Gleditsia triacanthosGleditsia triacanthos

Gleditsia triacanthos Gleditsia triacanthos varvar. inermis. inermis

Gleditsia triacanthos Gleditsia triacanthos varvar. inermis . inermis ‘Skyline’‘Skyline’

The EndThe End