- Botanical studies organise plants into genera families and species
- Plant families are often very logical and easy to learn
- Using Latin names when describing plants tells you about the plant’s family
What is Botany?
Botany is the study of plants. Botanists collect plants into ‘families’ based on similar characteristics. All members of each plant ‘family’ have similarities in their flower structure and are thought to have descended from a common ancestor. Note that the family names of plants usually end in ‘CEAE’ and are always capitalised when written. For example, the MYRTACEAE family is one of the largest families of Australian plants. The word MYRTACEAE comes from the Greek word ‘Myron’ meaning perfume which refers to the characteristic fragrance of many members of the MYRTACEAE family. Some of the main characteristics of the MYRTACEAE family are:
- leathery leaves which are dotted with transparent oil glands
- hard, woody fruits capsules which open at the top to release many tiny seeds.
Each ‘family’ is further divided into a number of ‘genera’ and these genera further divided into ‘species’ which have more similar genetic characteristics. Some of the genera in the MYRTACEAE family include Eucalyptus, Melaleuca and Leptospermum. Ultimately each group of plants which appear to have the same structures are given the same name and no two different species may have the same name. The Eucalyptus genera has more than 600 species. A couple of local species include Eucalyptus camaldulensis (River red gum) and Eucalyptus leucoxylon (SA blue gum). This system of classification and naming of organisms is used for all living things all over the world e.g. humans are Homo (genus) sapien (species).
The use of Latin and Greek words ensures consistency of names regardless of the language of the user. The common name often derives from a feature of the plant, e.g. Grey box relates to the colour and type of bark, River red gum relates to where the tree prefers to grow and the colour of the timber. Common names for birds are often formed in the same way e.g. Yellow-tailed black cockatoo and Red wattlebird. Many people find common names a lot easier to remember but common names are not always useful for telling us about the family or ancestry of an organism. For example ‘Kangaroo thorn’ does not tell us that this plant is a type of Wattle or Acacia. Common names can sometimes vary between botanists and publications. Occasionally two different species may be given the same common name or there may be more than one accepted common name for the same plant. This can be a problem if we are trying to work out precisely which plants should be growing in a particular area. Using the botanical name ensures that there is no confusion about which species is being discussed.
Monocot or Dicot?
Botanists use many attributes of plants to assist them in identification. In South Australia we have mostly flowering plants, or angiosperms. Of the gymnosperms, or non-flowering plants there is only one, the CUPRESSACEAE which includes the native pine genus, Callitris.
The first step used to identify flowering plants (angiosperms) in almost any plant identification book ever published, is to determine whether the plant is of the class DICOTYLEDONEAE or MONOCOTYLEDONEAE. This subdivision is based on whether the embryo (seed) of the plant will sprout one or two cotyledons (leaves) when it germinates.
How to Distinguish Monocots and Dicots
Monocots (short for ‘monocotyledon’, ‘one leaf’) are flowering plants, with one vertical grass-like baby leaf. They include local indigenous plants such as Common vanilla lily, Garland lily, Kangaroo and Wallaby grasses, as well as orchids, bamboo and palm trees (including bananas). Most of the world’s cereal crops such as wheat and barley are also monocots.