Plant Family Classification

Recently I have been busy researching and writing all manner of plant related areas and have developed a new realization of how plants are connected from the past to the present, and from one part of the world to another, just as we are. Until now, it never occurred to me that the mums on my porch are possible direct descendants of one, on another porch, in another country long ago or that someone in a distant country may be watering their own pot of mums.

 

 Certainly being inspired by my garden has led me on some unexpected paths. Even in reading about many of the common plants I have written about, the Asteraceace family keeps popping up. With my curiosity peaked, I began to look at the connections between plants and have discovered the scientific classification of all living things. While we humans are on another branch… all life on this planet is a part of the tree!

Perhaps my condensed version of plant classification will interest you to read on and provide you with a basic understanding of plant names you see printed everywhere.

 Classification

Taxonomy, from the Greek words “taxis” or arrangement and “nomia” which means method, is the name given to the academic method of classifying all living things. This method groups organisms that share characteristics and gives each group a name. Then the scientific community has placed these groups in a hierarchy based on their order of importance, which shows where that group fits in the big picture.

The biological classification is very complicated once you delve in to it, but on a simple level it gives the relative connection between organisms or plants. To do this, it uses taxonomic ranks, including, among others (in order from most inclusive to least inclusive): Domain, Kingdom, Phylum, Class, Order, Family, Genus and Species. Living things are classified into five kingdoms that are Prokarya, Animalia, Plantae, Fungi and Protoctista. Of course we are far down the Animalia branch, just as the plants in our gardens are down in the Plantae branch, but today I am checking out plant classification while leaving the humans being…

 

 

 

 

Read more at Buzzle: http://www.buzzle.com/articles/classification-of-living-things.html

Plant classification beginnings

 

Aristotle to Pliny the Elder:

Historical records reveal that early forms of organism classification begin with Aristotle (Greece, 384-322 BC) who began some of the first recorded plant studies. One of his students named Theophrastus (Greece, 370-285 BC) continued the work and wrote a publication classifying 480 plants including Crocus and Narcissus which are still used today. Pliny the Elder (Rome, 23-79 AD) wrote a 160-volume work which described a large number of plants even giving some Latin binomial names.

 

 Pre-Linnaean plant taxonomists:

While many learned scientist worked on plants worldwide, I found that records stated that no significant taxonomic works replaced the ancient texts for approximately 1500 years as the visual and physical means were exhausted. With the development of the early optical systems such as magnifying glasses and microscopes, classification began in earnest again, as the structure of organisms could be studied in detail.

 

early compound light microscope

 

 

Globally the botanists and other scientists worked on studying plants and classifying them. I could find no females listed although I am certain they did exist. Instead, I have included only a sampling of the male botanists who impacted the taxonomy of plants through the years.

Andrea Cesalpino ( Italy, 1519–1603),  wrote a book  that described over 1500 plant species, including two large plant families Asteraceae and Brassicaceae which are still in use today.

 

 

 

 

 John Ray (England, 1627–1705) wrote a large number of significant taxonomic works with information and classifications of over 18,000 plant species.

Gaspard Bauhine (Switzerland 1560 m-16624)in his work Pinax, proposed two name classification of over 6000 plants.

In the same time frame, the next major taxonomic works were produced by  Joseph Pitton de Tournefort (France, 1656–1708), which included over 9000 species in 698 genera. History states that these works specifically influenced one young student Swedish student named Carolus Linneaus.

 The Linnaean era:

Carolus Linnaeus( 1707-1778) became a botanist who led the field on plant classifying. He published major works and fully put in to place the binomial naming system that had begun with his predecessors.

 

Many of his works, including the largest publications Species Plantarum ( The Species of Plants 1753) and Systema Naturae were translated to English making them more accessible to the scientific world. In fact, Erasmus Darwin, grandfather of Charles Darwin, translated many of Linnaeus’s published works. Even today, before naming a new plant discovery, Linnaeus’s work is used as the reference point to ensure any name chosen for it, has not been previously used.

The Binomial System:

Based on the largest system of plant identification groups, plant tags in nursery pots would need to be huge! Certainly each plant belongs to a Family, whose name always ends in “aceae”. All members of a particular family share certain groups of characteristics that are not found in other families.

For example, looking up Family names such as – Rosaceae (rose family) or Liliaceae (lily family) provide information and understanding of all the plants in that family. Examples of this information would include data on the plants requirements to grow, the physical characteristics, seed information and more found below the family classification, comes the two levels that make up what is known as the Binomial System.

Whether aware of it or not, most gardeners worldwide are  familiar with the Binomial System as commonly displayed on nursery stock plant tags .Until I looked in to classifications, I knew of Genus and Species,  but generally referred to plants by what is their “common name”. The biggest drawback here is that there are many common names for any one plant. According to one article I read, the White Lily and marsh marigold both have over 200 common names.

Thankfully, the scientific community uses the more precise Binomial system in naming of a plant and for further understanding of the characteristics of the group that plant is classed in. While this system was introduced by several men, it was to Carolus Linneaus who is credited with permanently ensuring the advancement of this system. Expressed in Latin, the twodivsions are the genus and the species.

 

 

Genus:

Each plant family is further divided in to groups of plants that are more closely related, with from one genus to as many as 950 genera (plural). The first part of the binomial system is the genus and it always starts with a capital letter.

 

Species:

Each genus is further subdivided into species. This is the second word in a plant’s botanical name and begins with lower-case letters. Most genera contain two or more species that share most characteristics and reproduce by seed with minor variations. In addition members of a species do not usually interbreed successfully with members of a different species. Species names begin with lower-case letters.

 

Genus and Species name selections:

There are many ways these names were determined, including choosing a name to honour the person who discovered the plants, a famous person they admire or even the country the plant originated from. One good everyday example of this is the Coffee Plant. The official genus name  comes from one aspect of the plant…its use as a beverage….so it is named after Coffea, the Latinized form of the Arabic word for beverage. The species name of Arabica, was given as the plant was thought to have originated in Arabia. So now anywhere in the word you see a plant with the botanical name, Coffea Arabica, you would find the same unique plant.

 

Coffea arabica

 

For the scientific community these classifications ensure that any further identification and research across the world, is connected and all information shared applies to the same plant no matter where it is located. Still plant classification can be difficult as some species in nature closely resemble another, there is interbreeding that produces subspecies and hybrids even in the wild.

 

Subspecies, Variety:

If there is a third word, or short form such as subsp, ssp., or var., in a plants botanical name, that indicates a subspecies or variety.  While these terms are not interchangeable to a botanist, to regular people it means the plant has most characteristics of their species with a slight difference such as in flower color or leaf size. These plants can interbreed to form fertile seeds that will grow in to identical plants.

 

Cultivar: (horticultural variety or clone)

A cultivar is a plant or group of plants propagated by careful breeding for some desirable characteristic. Their name is usually the genus name with the species, followed by the cultivar name in quotation marks.  One example we see regularly are popular ornamental garden plants like roses ,camellias, daffodils, and azaleas where cultivars are deliberately bred for colour and form .Even the vast majority of the world’s food has been cultivated and selected for resistance to disease, improved yields and flavours.

 

Hybrid:

This is a distinct plant resulting from a cross between two species, subspecies, varieties, cultivars, strains – or any combination as well as between two plants belonging to different genera. While some hybridization can occur in the wild, usually it is done deliberately by horticulturalists trying for an effect, such as those trying to hybridize African Violets that produce a blue flower. Unfortunately often hybrids cannot produce fertile seeds or if seeds are produced they grow the stronger strain or plant used. Once I had an odd annual hybrid plant thet was a lime green instead of its usual white and the plants began to revert even before seeds were produced.

Strain:

Many popular annuals and some perennials are sold as strains that are usually the result of breeding and deliberate selection for a certain characteristic like height or flower colour. Again those characteristics can easily disappear in the next generation of the plant, especially if left to pollinate naturally.

http://theseedsite.co.uk/families.html

From the plant world’s point of view classification has gone from B.C. era where studying was done by sight, scent and physical characteristics to DNA studies which are used in Genetically Modifying plants. But, as far as gardeners are concerned whether it be annual, perennials, vegetables or trees and shrubs, how they adorn out gardens and life our spirits is the most important thing.

From garden centres and green house, plants come in all shapes and sizes no matter where in the world we are. The tags generally contain information on each one, certainly the genus and species name, which has more history and information attached to them than we realized. Now when I buy a plant I can almost imagine someone in their country garden on the other side of the world… reading the same plant’s tag !

 

2 thoughts on “Plant Family Classification

    • Hi Banele Shiba

      I am haapy to have been of help to you.Classification is an interseting area and I learned a great deal while researching the subject.You are most welcome and if You have any further questions I would be glad to help.
      Linda

Leave a Reply

Your email address will not be published. Required fields are marked *