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Lesson 1 INTRODUCTION - The Why Suggested Tasks: ▼ and How of Names Throughout this course you will be provided with suggested tasks and reading are critical to human existence. They provide much of our food, to aid with your understanding. fuel, building materials, compounds for pharmaceuticals, and they These will appear in the right hand column. Remember: satisfy many other needs. They are an integral part of our environment these tasks are optional. The where they provide ecosystem services such as clean water and more you complete, the more filtered air, as well as a food source for pollinating insects and birds you will learn, but in order to which, in turn, ensure the provision of our crops. Plants also have a complete the course in 20 profound effect on both our physical and psychological wellbeing. hours you will need to manage your time well. We suggest you spend about 10 minutes on each task you attempt, and no more than 20 minutes.

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Suggested Tasks

Before progressing; spend 5 mins to quickly write a list of reasons why you think it is important to be able to English Lavender (Lavandula angustifolia) Because this is the only lavender with identify plants accurately. very low levels of camphor oil; it is the only species able to be used to flavour foods. Get Put the list to one site. the identification of lavender wrong, and you may be ingesting unsafe levels of camphor oil. You will refer to it again later.

Why Name Plants? a dramatic and potentially fatal effect on us or anyone who we advise. For The immense significance of plants example, “People have died after in our lives has led to a desire to mistaking deadly nightshade fruits, for understand plants. Knowing shared the similar, but non-fatal, black-currants.” characteristics of a plant group, allows us to predict traits of related and even Accurate plant identification is a unknown plants. Mankind has had skill which should be an essential to rely on plants for survival. In fact, requirement for anyone working with around one third or more of all plants plants and especially in horticulture. in cultivation contain toxic chemicals. is the term used to describe If we were to incorrectly identify and the practice and science of naming name plants we may use these plants and classifying any organisms, and in inappropriately, and that could have our case plants. It relies on accurate

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descriptions and rules of nomenclature distinction between types of horticulture to facilitate identification. To attempt is ornamental vs. edible. Within this Learn More ››› to select, grow, and use plants in any grouping though, are many subtypes context without taxonomic skill is at of horticulture, such as ornamental Suggested Tasks best foolhardy, and at worst it can be horticulture, amenity horticulture, outright dangerous. arboriculture, floriculture, and more. Make a list of 5 plants that are poisonous. For each The necessity of understanding correct It’s also important to draw a distinction plant, note down things like plant identification, however, goes far between horticulture, professional what it is used for, they type beyond recognising poisonous or toxic gardening, and gardening. Horticulture of poison, the effects of the plants. Plants are a vital part of societal is a science. It uses research-based poison, how to avoid it etc. infrastructure, with uses ranging from methodology to improve plant growth, Spend up to 15 minutes on the home gardening and landscaping health, propagation techniques, and this task. through to coastal stabilisation, carbon more. Professional gardening is the sequestration, therapeutic use, and professional care of gardens, public If need be, search books more. In accurately classifying and spaces, and other areas. While many or the internet, or have a recognising plants, horticulturalists, professional gardeners are also discussion with a horticulturist agriculturalists, gardeners, and other horticulturalists, their primary activities to compile this list. professionals can work together to better differ: professional gardeners are in everything from cityscapes to food the business of caring for, supervising, production. In short, plant taxonomy is a and improving their environments. Both necessary real-world skill. professions require skill and hard work.

There are also economic reasons Horticulture and professional gardening for being able to identify plants. The are also distinct from gardening or home development of new plant cultivars gardening. Home gardening is the care can be time-consuming and costly, of a garden for pleasure or domestic but it is very important to commercial use (such as a vegetable patch, or horticulture in order to improve ornamentals for pleasure). It is a hobby continually the cultivars available in as opposed to a profession. terms of productivity and quality. Anyone who devotes significant resources to developing a new cultivar needs to be able to establish and prove their commercial rights to that plant in order to obtain fair and profitable gain from their investment. Systems for establishing such rights exist in most developed countries.

It is also important to note that horticulture is a vast and diverse scientific field. Even if you don’t work Cydonia oblonga has the common as a horticulturalist, it’s important to name Quince, but so does the understand there are different types genus Chaenomeles. of horticulture. The biggest modern

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Scientific Vs. can therefore be understood equally by anyone, anywhere, regardless of Vernacular Names their native language. The Latin name A vernacular name is a common or ensures that people are referring to the local name given to plants. These names exact same plant. are widely used amongst gardeners and non-horticulturists. There are advantages to these vernacular names. For example, they are in the local language and thus easier to remember. They are also often descriptive with the description indicating a use or danger. However, there are also drawbacks with common names. They can be very localised and the same plant can have more than one common name for example, the White Waterlily (Nymphaea alba) has many other common names, such as European White Waterlily, Waterlily, and White Lotus. Further confusion is created when Chaenomeles species are commonly the same common name is applied to called Flowering Quinces. So different plants. For example, Nymphaea are Cydonias. Both are in the lotus is also called White Lotus and Rosaceae family. White Waterlily, along with other names like Egyptian Lotus, Egyptian Waterlily and White Egyptian Lotus. Another History example is the common name Quince which is used for both Cydonia oblonga To gain a solid grounding in plant and Chaenomeles species. naming, a little historical background information is helpful. Some common names are the same as the Latin name. For example, plants John Ray in the genus Euphorbia are often referred to by gardeners simply as John Ray (also spelled Wray) was an euphorbias, although they can also be English naturalist who lived between called spurges. Likewise, species in 1627 and 1705. He was one of the the genus Rhododendron are called most important figures in the early rhododendrons, but some of them are development of plant taxonomy. In called azaleas even though they are 1660, he published a catalogue of in the genus Rhododendron! Extreme plants which were growing around confusion can result from the fact that Cambridge in England where he “fritillary” is a common name for both studied his Bachelor’s degree. Over the a bulbous plant and a butterfly. decades that followed he explored plant life throughout other parts of the UK, Scientific names on the other hand are and he continued publishing important all written in the Latin language. They taxonomic works. His most important

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long-term legacy was to establish the importance of distinguishing plants at a Learn More ››› species level and using every part of a plant when grouping them, and not just Suggested Tasks relying on one, such as leaf shape or flower colour. For each of the following plant categories, find one species. Linnaeus Type your chosen species into the search engine and (1707-1778), who was look up images. View the a Swedish botanist and zoologist, is different images to gain an widely regarded as the most significant Fritillary is a common name used for appreciation of variation figure in establishing the scientific the plant genus (Fritillaria) and also for a within the same species. system of taxonomy. type of butterfly. ■■ Grass Binomials Uniformity ■■ Climber Linnaeus achieved his standing largely by formalising the practice of binomial It wasn’t until 1867 at the inaugural ■■ Hedge naming of plants and animals (where bi ‘International Botanical Congress’ means two, and nomial means name). that the first set of rules underpinning ■■ Shrub That is, he used the genus together plant names was officially adopted by with the species name to identify an the botanical world as an international ■■ Fruit tree organism with “two names” e.g. Quercus scientific standard. robur (English Oak) or Rhododendron Spend about 10 minutes on ponticum is the rhododendron from the Deficiencies in this original code led to this task. Pontic Mountains in Turkey. the establishment of a number of other sets of rules. A compromise between His work “Systema Naturae” was first the existing codes was adopted in published in 1735 as a 12 page book 1930 and published as the 3rd Edition and was developed and expanded of the International Rules of Botanical over more than 2 decades until the Nomenclature. More recent editions are 10th edition in 1758 which covered basically modifications of this code. some 7,700 species of plants and 4,400 species of animals. By this Many amateur gardeners make the time, specimens of plants and animals mistake of not using proper identification were being sent from all around the systems. They commonly identify plants world for Linnaeus to catalogue. Many by simply accepting the name on a label other works relating to plant taxonomy when they purchase a plant or the name emerged throughout Linnaeus’s lifetime, they are offered by someone else who some by Linnaeus himself, and some gives them that plant. They may also by others who were heavily influenced identify plants by looking at photographs by Linnaeus’s thinking. The evolution in a book until an image can be matched of taxonomy beyond Linnaeus has with the plant being observed. Such arguably been influenced more by methods may be adequate for some Linnaeus than anyone else. plants grown in a home garden, but

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they cannot be guaranteed as accurate for most plants. Even within the same species there can be tremendous variation in plants which adds to the confusion. For instance, you can find two plants of the same species which have grown to different heights and widths. There may also be variation in leaf shapes and sizes depending on the health and vigour of the plant, and even the colour of the flowers may vary.

The accurate scientific name of a plant cultivar can only truly be determined by scientific examination of the plant. There are two ways to do this:

1) Anatomical based classification - this is the traditional way of identifying plants. It involves closely examining a plant with a hand lens to determine its physical characteristics such as flower structure (e.g. number of petals, inferior or superior ovary etc.), shape of leaves, arrangement of leaves on a stem, the presence or absence of hairs, and The genus Acer produces a dry winged so forth. fruit called a samara.

The genus Zinnia produces a flower head composed of a mass of individual Fruit type is an anatomical feature. The flowers all composed into the one genus Rubus has an aggregate fruit. “composite” head.

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2) Genetic analysis - this is a relatively new method of identification and classification. DNA sequencing is having an impact upon plant taxonomy. Some plants which were previously classified as closely related using traditional anatomical comparisons have been found to be less closely related using DNA comparisons.

Paphiopedilum orchid cultivars can be identified by customs officials in some countries by genetic analysis. The genus Digitalis (Foxglove) produces a flower spike bearing many tubular flowers. With the correct equipment and data, it is also possible to use DNA sequencing to identify plant species. This is achieved using a technique called ‘DNA bar-coding’. For this to work there must be a special stretch of DNA present in every plant in the world. The sequence of this stretch of DNA must vary greatly between species but not vary between the individuals in the same species. Finding this bit of DNA has been elusive for plants and is actually much easier for animals. However, for some groups such as the orchid Paphiopedilum it has been Different plant families will typically achieved. This means that species and demonstrate different leaf characteristics, varieties of “Paphs” can be identified by either is appearance or how they are customs officials even when the plants arranged on the plant (or both). are not in flower – something that was impossible before.

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So far, the only country to have Ranks of Classification - successfully DNA bar-coded its entire KPCOFGS flora is Wales. For many plants, identification by DNA bar-coding is still The main levels of taxonomy in the a very long way off and so, for now at Plant KINGDOM, known as ranks, are least, the tried and tested technique of as follows: hand lens and anatomical description plus identification keys is here to stay! ■■ PHYLA (singular PHYLUM) are divided into CLASSES Ranks and Language ■■ Classes are divided into ORDERS The scientific system uses levels to classify plants by dividing them into ■■ Orders are divided into FAMILIES groups which have similar physical characteristics. These groups are then ■■ Families are divided into GENERA divided into smaller groups with more (singular: genus) similar characteristics. These are divided again, and so on. Therefore, the division ■■ Genera are divided into SPECIES of group to subgroup, and subgroup into further subgroups continues until you ■■ Species are sometimes divided finally have only one type of plant in into SUBSPECIES, VARIETIES, each group. or CULTIVARS.

Centaurea montana alba belongs to the order , the family , the genus and the species montana.

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There are many mnemonic or memory level which most horticulturists start devices which can be used to help you at, and then work down to genus and Learn More ››› to remember this sequence of ranks i.e. species. In fact, it could be argued Kingdom, Phylum, Class, Order, Family, that the only way to gain a reasonable Suggested Tasks Genus, Species which is commonly grasp of plant identification and abbreviated to KPCOFGS. The best culture is to learn plants by their family Choose a plant (any plant). way is to form a sentence using the as well as their genus and species Using the internet or other letters. A simple example is “King Philip names. Familiarisation with plant resources, find out what Came Over For Good Spaghetti”. Of families enables a person with no Kingdom, Phylum, Class, course, you could easily create your prior knowledge of a particular plant Order, Family, Genus and own sentence. to be able to place it in a family and Species it is classified as. For make an educated guess as to its each rank of classification In the scientific system of plant growing requirements, susceptibilities your plant belongs to, classification there are over half a million to environmental factors, possible form research the distinguishing species of plants. But what really is a and shape, and a range of other likely characteristics of that group to species? The classification of plants, characteristics. understand why your chosen like the classification of anything else, is plants belongs to that group. based on the idea of grouping together Plant Phyla things which are similar. Species are groups of individual plants that have The plant phyla we are concerned with a range of similar characteristics and in horticulture are: are capable of freely interbreeding with each other. That is, the pollen from the ■■ Angiosperms - this group includes flower of one plant can successfully all of the plants which produce pollinate the flowers of another, and the flowers e.g. eucalypts, roses, sperm in that pollen can fertilise the egg lettuce, grasses, etc. cells in the ovules of the second plant. This results in a fertile seed which will ■■ Gymnosperms - this group includes germinate and produce a new fertile all plants which produce cones e.g. plant that resembles its parents. It pines, cypresses, etc. should be noted that just because two plants can be hybridised in our gardens ■■ Monilophytes - this group includes this does not automatically make them ferns and horsetails. It is an ancient members of the same species. and large group containing about 12,000 species. They don’t bear Species are grouped together into seeds but instead have spores, collections of species which are fairly usually on the back of leaves. similar. These groups are called genera, with the singular being genus. ■■ Lycophytes - a small group of Genera are grouped into collections spore producing plants such as of genera which have a relatively club-mosses that were much more great similarity to each other. These important in the past are called families. Families are the

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Suggested Tasks

Take a 5 minute walk outside in a garden, park or anywhere else where there are plants. Look for a dicotyledon, and for a monocotyledon. When you think you see one; stop and look at the plant close up, noticing it’s characteristics. Start by looking to see whether leaf veins are parallel or not, but then look at other features beyond that.

Angiosperms – include a wide variety of plants, all which produce flowers

Angiosperms Monocotyledonae - also commonly abbreviated to the ‘monocots’. In these Angiosperms were traditionally divided plants, the first leaf to appear when a into two classes: seed germinates is a single leaf. Veins in the leaves are parallel to each other Dicotyledonae - also commonly and floral parts are in multiples of three. abbreviated to the ‘dicots’. In these Examples include: grass, Iris, and plants the first leaves to appear from the orchids. a germinating seed are in a pair (two leaves appear at once). The veins in the It should be noted that one of the first leaves are not parallel in these plants major changes in plant classification and flower parts are in multiples of two to result from DNA sequencing was or five. Examples include: tomato, pea, the fact that a few of the families in Eucalyptus, maple, Rhododendron, the dicots were taken out of the class. and Banksia. Those that were left are referred to as

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the true dicots, or . Common plants that were removed from the dicots Learn More ››› are the water lilies and the magnolias. Suggested Tasks

Type in the following words into your search engine (or google):

“Videos monocot dicot germinating seed”. Watch a couple of videos that shows you the differences between monocots and dicots. Spend up to 10 minutes on this task.

Gymnosperms include plants that produce cones; but not flowers

Cordyline is a monocotyledonous genus in the family Asaparagaceae

These are dicotyledons. When a Monilophytes do not produce seed, but dicotyledon seed germinates, two usually produce spore on the back of leaves emerge together; with a their fronds. monocot, only one leaf emerges first.

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Plant Families You should be able to tell a family name from other types of names by the fact It can be seen from above that you can that it will end with “-aceae”. Students distinguish between dicotyledons and sometimes confuse the family name monocotyledons by a couple of very with genus, but a genus name virtually simple characteristics. In the same never ends in the letters “-ae” and way, we can usually distinguish which never “-aceae”. family a plant belongs to by a few basic characteristics. For example:

■■ Lamiaceae - the flowers have two distinct lips, the leaves are opposite, the stems are square, and the leaves are often hairy and scented e.g. lavender.

■■ Araceae - leaves are usually heart- shaped, they have tiny flowers on a spike enclosed in a leaf-life bract, and the plants are commonly tropical/ indoor plants e.g. Philodendron.

■■ Asteraceae - they have daisy-like flowers which are in fact a bunch of flowers e.g. Dahlia and sunflowers. Apiaceae - flowers occur in an umbrellalike head on a single stalk e.g. parsley. Family Apiaceae - Dill (Anethum graveolens)

Family Asteraceae - aristata ‘Amber Wheels’ Family Araceae - Caladium

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