Understanding Plant Classification

Plant taxonomy or classification is the science of naming organisms and placing them in a hierarchical structure each level being given a name.

All living things were traditionally placed into one of two groups, plants, and animals. This classification may date from Aristotle ( 384 BC- 322 BC)

In this blog, I am going to focus on the labels that come with plants or in books to help educate you on what all the “latin” means. I will continue part 2 of this article and break it down even further.

The order as a distinct rank of biological classification having its own distinctive name (and not just called a higher genus (genus summum) was first introduced by the German botanist Augustus Quirinus Rivinus in his classification of plants that appeared in a series of treatises in the 1690s. Carl Linnaeus was the first to apply it consistently to the division of all three kingdoms of nature (then minerals, plants, and animals) Naturae.

What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. The listings are changing often as more study and research is done.

” Dear King Phillip Came Over For Good Soup”

Does this quote sound odd? when it is it is used to memorize taxonomic classification it will make sense. This is a listing of the 8 levels of classifications for plants.

Dear=Domain

King=Kingdom

Phillip=Phylum

Came= Class

Over=Order

For= Family

Good= Genus

Soup= Species

Here is a quick explanation of each classification. They rank in importance in this order.

DOMAIN– also dominion, super kingdom, realm, or empire, is the highest taxonomic rank of organisms in the three-domain system of taxonomy devised by Carl Woese et al. in 1990. There are 3 agreed groups at this level, the Archaea, Bacteria, and Eukarya domain. * See the next blog #2 for more in-depth study on these.

KINGDOM– is the second highest taxonomic rank. Kingdoms are divided into smaller groups called phyla. Traditionally, some textbooks from the United States and Canada used a system of six kingdoms while textbooks in Great Britain, India, Greece, Brazil, and other countries use 5. The six are: Eubacteria, Archaebacteria, Protista, Plantae, Fungi, Animalia * see blog #2 for more in-depth study.

PHYLUM – in botany the term division has been used instead of phylum. The 4 categories are Chlorophyta, Bryophyta, Pteridophyta and Magnoliophyta

CLASS – is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank.

FAMILY – A family may be divided into subfamilies that share a common attribute. Plant families are separated according to structural differences in flowers, fruit, seed

GENUS – used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus.

SPECIES A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behavior, or ecological niche.

So to review a label for a plant in a guide book the label can be explained as follows.

1. The Kingdom is Plantae- or Kingdom of plants

A clade, also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. In the case of this listing, it has 3 listings that describe its features.

2. Tracheophytes- refers to the water-conducting cells called tracheids that show spiral bands.

3. Angiosperms refer to a plant that produces seeds enclosed within a fruit.

4. Monocots- refers that the seed typically contain only one embryonic leaf or cotyledon

5. Asparagales- it is a listing in the lilioid monocots

6 Asparagaceae- it is the family of asparagus

7. Agavoideae- a group of well-known desert and dry-zone type of plants

8. Agave is the plant name

So the next time you look at an Agave plant, giggle to yourself that it shares a botanical line with asparagus. The breakdown had a lot of terms which can be overwhelming but remember when these terms were first created Latin was the verbiage used in that time period. Most garden enthusiasts use common names, not Latin names.

Remember to stay tuned for article 2 where I will break down the list even further.