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THE KINGDOM

(UNIT 1)

Lesson 1 CLASSIFICATION OF AND THE PLANT NAMING SYSTEM

Aim Describe the classification of higher plants. Name the main plant groups; outline their characteristics and life cycles.

BOTANICAL/HORTICULTURAL NOMENCLATURE

Plants are generally given two different types of names: common names and scientific names.

Common English language names usually given to plants by amateur gardeners as a Names descriptive, easy-to-remember tag. Many plants have more than one common name, and sometimes the same common name can be given to several quite different plants. This, along with the fact that there is no real control over common names, makes them inaccurate and unreliable for plant identification.

Scientific Based on the Latin language, these names often seem more complex than Names common names at first glance; however, they have a system to them which can make plant identification much easier. The system of scientific naming is strictly controlled and coordinated by botanists throughout the world. Scientific names should always be used in preference to common names. Much of the Latin in scientific plant names will describe certain characteristics about a plant, thus, knowledge of Latin can be of help when studying plant names but it is not essential.

The Binomial System

The scientific plant names, which you see in books or on plant labels in a nursery, usually consist of two words. This is called the binomial naming system:

e.g. Azalea indica Azalea indica

The first word is the name of the plant. The second word is the species name of the This word starts with a capital letter. plant. In general, this word starts with a lower- case letter. There are exceptions to this rule - some people capitalise the first letter of a species name where a species has been named after a person or country. However in recent years this is no longer the accepted way to write a species name and now all species name irrelevant of whether it is a name or not start with a lower case letter.

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When writing a scientific name of a plant, it is conventional to either italicise or underline both words in the name e.g. Azalea indica or Azalea indica . (Italicising is more common.)

Botanical Classification

In the scientific system, plants are classified by dividing them into groups, which have similar characteristics. These groups are then divided into smaller groups with similar characteristics. The smaller groups are divided again and, so, the division of group to sub-group and sub-group to further sub-groups goes on, until finally you have only one type of plant in each group.

The two major groupings of organisms are kingdoms: the plant kingdom and the animal kingdom. Following this, the main levels of divisions of plants are:

All plants are divided into PHYLA (singular: phylum) Phyla can be divided into DIVISIONS Divisions are divided into CLASSES Classes are divided into ORDERS Orders are divided into FAMILIES Families are divided into GENERA (singular: genus) Genera are divided into SPECIES Species are sometimes divided into VARIETIES

Although there are many levels of division, the main ones we work with are at the lower end of the divisional scale: family, genus, species and variety/sub-species.

Horticultural Phyla The main plant phyla we are concerned with in horticulture are:

• Anthophyta (i.e. angiosperms). This group includes all plants that produce , e.g. eucalypts, , lettuce, grasses. They are seed-bearing plants.

• Coniferophyta (i.e. gymnosperms - ). This includes all plants that produce cones, e.g. , cypress, junipers. They are naked seed-bearing plants.

• Pterophyta (i.e. ). This includes plants that reproduce by spores rather than seeds.

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Other phyla include such things such as mosses, fungi, bacteria and algae.

Anthophyta is divided into two classes:

1. Dicotyledonae . In these plants the first to appear from a germinating seed are in a pair (two leaves appear at once). In general, the veins in the leaves of dicotyledons are reticulate not parallel (e.g. pea, eucalypt). Dicotyledons (commonly called dicots) also tend to have a taproot with lateral branches, as opposed to a fibrous system.

Note: Reticulate venation is when the main veins on the leaves branch out; with smaller veins arising from the larger ones.

2. Monocotyledonae . In these plants the first to appear when a seed germinates is a single leaf. In general, the veins in the leaves of are parallel to each other extending up the leaf (not spreading). Monocotyledons (commonly call monocots) also tend to have a fibrous root system, as opposed to a taproot with lateral branches. Grasses, irises and orchids are examples of monocots.

SELF ASSESSMENT Perform the self assessment test titled ‘Self Assessment Test 1.1’. If you find yourself getting the answers wrong, revise the notes from this lesson and repeat the test.

Plant Families and Species It can be seen above that you can distinguish between dicotyledons and monocotyledons by a couple of very simple characteristics. In the same way, we can usually distinguish which family a plant belongs to by a few basic characteristics. For example: • Lamiaceae family: foliage is perfumed, stalks are four-sided (i.e. square-shaped) and flowers have two distinct lips (e.g. Mint spp.). • Araceae family: leaves are usually heart-shaped and the plants commonly originate in tropical regions (e.g. Philodendron ). • : plants in this family have ‘daisy’ flowers (e.g. ). needs italics • : flowers occur in an umbrella-like head on a single stalk (e.g. Parsley Petroselinum spp.).

You should be able to tell a family name from other types of names by the fact that it will end with "aceae". Genus names do not end in ‘ aceae’ .

For example: Eucalyptus ficifolia

Eucalyptus is the genus, ficifolia is the species The family this plant belongs to is the Myrtaceae family.

3 Sometimes a third word (and perhaps a fourth) is added to follow the species. These words refer to the variety of that particular species.

For example: Acer palmatum var. dissectum Atropurpureum Group

Acer is the genus palmatum is the species dissectum tells us this is a variety of Acer palmatum with dissected leaves. Atropurpureum Group tells us this variety belongs to a group of Acer palmatum var. dissectum that have purple foliage.

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Sub Species Sub-species are a naturally occurring geographical variant of a species – in order it is a taxonomic rank directly below species. Subspecies names are either recognised by the abbreviation subsp. or ssp. (not to be confused with spp. which is explained below).

For example: Acacia terminalis ssp. terminalis

See above: all the words in a plant name that includes a subspecies are in italics - other than the abbreviation for sub-species.

Note: the abbreviated term spp. (meaning: species plural) refers to all the species in that genus and is sometimes used when the writer is referring to most of the species in that genus (i.e. for example Rosa spp. meaning (generically) all species). A writer might say “Rosa spp. are prone to black spot”; they may know that many species are not prone to black spot but because so many are they do not want to write a definitive list. If you see the abbreviated term sp. (species) it means that the writer is referring to a single unknown species within a known genus e.g. “I saw a beautiful plant – a Rosa sp.”

Hybrids, Varieties and Forms You may be confused by the difference between hybrids, varieties, forms and . A hybrid plant is one which has resulted from two different species cross breeding. The parent plants are almost always in the same genus. Most hybrids are deliberately bred by humans, although some occur in nature where the distributions of the two parent species overlap. For example, Eucalyptus ‘Torwood’ is a cross between Eucalyptus torquata and Eucalyptus woodwardii . Sometimes the two plants which have been cross bred are both mentioned and an "x" is placed between them, e.g. Eucalyptus torquata x woodwardii. If a plant is a cross between two genera then it would be depicted (for example) as follows: x Cupressocyparis leylandii

A variety (shown in a botanical name as var.) or form (shown as f) is a particular type of naturally occurring plant in one species. It displays minor variation/s from the typical species for example: a variety may be larger than the typical species plant; a form may have lesser difference e.g. it may have a cream instead of yellow ). A variety (correctly known as varietas) of form (correctly known as forma) do not have parents from two different species, but a hybrid does.

Examples of how to correctly depict variety and form in a botanical name: Gleditsia tricacanthos var. inermis moschata f. alba

Note: variety and form names are written in italics and start with a lower case letter. The abbreviations var. and f. should not be italicised.

Cultivars The word is derived from the words cultivated variety . The accepted meaning of the word cultivar varies somewhat. In general, a cultivar is a group of cultivated plants (bred by people i.e. not a natural variant like a variety or form) that are clearly distinguishable from others by a certain characteristic (for example a certain flower colour, leaf colour or shape etc.). This characteristic must be passed on to the offspring (whether produced sexually or asexually) of the plant for it to be a true cultivar.

In some countries, the word cultivar means the same thing as a variety (but this is not botanically accurate). It is acceptable to refer to a cultivar as a variety when you can easily tell it is actually a cultivar, for example: ‘Joan’. Problems may arise however when you are looking at older texts or referring to old cultivars which may have a Latin name. Modern cultivars now must all be given non-Latin names, whereas older plant cultivars often had Latin names and that makes them hard to distinguish from a variety. So if in doubt refer to all cultivars as those that are specifically bred by 5 human intervention and all varieties and forms as those that are naturally occurring through the intervention of nature.

Examples of how cultivar names should be written – note cultivar names appear within single inverted commas and are not italicised: angustifolia ‘Hidcote’ officinalis ‘Benenden Blue’

Cultivars are named by using rules and guidelines set by International Code of Nomenclature for Cultivated Plants. All other plants (other than cultivars) are ruled by the International Code of Botanical Nomenclature. These rules are revised from time to time to ensure that the confusion surrounding plant names and classification is minimised. Names may also be changed when the International Botanical Congress sits approximately every 6 years - as new evidence comes to light regarding individual plant (DNA testing is becoming a very useful tool in plant identification).

Note: the first name to be validly published for a plant is its ‘true’ name and no other plant can subsequently use that name. ‘Valid’ publication means that the plant name was published according to the rules of the code.

Considerations in Naming Cultivars Firstly the breeder does checks to ensure the plant is a genuine cultivar; a single plant is not considered a cultivar. The breeder must have a group (of a single plant) that is collectively distinct from any other group in that species. They must be uniform in appearance and be stable i.e. retain their characteristics or traits. The breeder will compare the new cultivar to others in the species to ensure that the cultivar is actually new.

Secondly the breeder will make sure that this cultivar is actually worth naming – it must be an improvement on the species. It takes a lot of work and research and a stringent selection process to come up with a viable new cultivar worth naming.

When naming a new cultivar it will have a genus name, sometimes the species name is listed too (although this is not entirely necessary it does give a further clue to the plants origin) and then the cultivar name appears within single (never double) inverted commas, in a language other than Latin and unique within the genus it belongs to. Cultivar epithets that are not within the rules of the code are rejected by the code.

The breeder with register the name with a statutory plant authority - they usually can inform the registering party if the name is already in use. Each authority will have its own codes or rules that the breeder needs to apply with.

SELF ASSESSMENT Perform the self assessment test titled ‘Self Assessment Test 1.2’. If you find yourself getting the answers wrong, revise the notes from this lesson and repeat the test.

6 BOTANICAL FAMILIES OF GENERA

The following lists show some of the most common botanical families and horticultural genera within those families. These are just a sample – there are many others which, no doubt, you will come across in your studies and work, but you may use these lists as a guide to labelling your plant collection specimens. Dicotyledons , Aphelandra, Hypoestes (freckle face), Justicia, Pachystachys, Thunbergia Anacardiaceae Cotinus (smoke bush), Mangifera (mango), Pistacia, Rhus, Schinus (pepper )

Apiaceae Actinotus (flannel flower), Angelica, Daucus (carrot), (sea holly), (Umbelliferae) Foeniculum (), Petroselinum (parsley)

Asteraceae Achillea, Ageratum, Anthemis, Aster, Brachycome, , Chrysanthemum, (Compositae) , Cosmos, , Gazania, Gerbera, (sunflower), Helichrysum, Olearia, Osteospermum, (cone flower ), Santolina, Senecio, (marigold), (dandelion) , Zinnia

Betulaceae Alnus (alder), Betula (birch)

Bignoniaceae Bignonia, Campsis, Catalpa, Jacaranda, Pandorea, Paulownia, Pyrostegia, Spathodea (African tree), Tecoma, Tecomaria

Brassicaceae Alyssum, , Aubretia,, Brassica (cabbage, cauliflower), (Cruciferae) Cheiranthus (wallflower) , Lobularia (sweet alyssum), Matthiola (stock), spp. Nasturtium

Caprifoliaceae Abelia, Kolkwitzia, Lonicera (honeysuckle), Viburnum, Weigela

Caryophyllaceae (carnation), , Lychnis (campion)

Epacridaceae Astroloma, Epacris, Leucopogon Ericaceae Arbutus, Erica, Pieris, Rhododendron

Euphorbiaceae Acalypha, Codiaeum (croton), , Omolanthus, (castor oil plant)

Fagaceae Castanea (chestunut), Fagus (beech), Quercus (oak)

Gesneriaceae Achimenes, Columnea . Gloxinia , Saintpaulia (African violet)

Goodeniaceae Dampiera, Goodenia, Leschenaultia, Scaevola

Hamamelidaceae Corylopsis, Hamamelis (witch hazel), Liquidamber, Loropetalum

Lamiaceae Ajuga, Lavandula (lavender), (), Mentha (mint), (Labiatae) (, ), (), Prostanthera, Rosmarinus (), (lambs ears), Salvia (sage), Westringia

Legumes NB: Strictly speaking legumes have now been split into three families: Mimosaceae, Caesalpinaceae and . At this stage in your study you 7 may, for simplicity, classify all pod-bearing plants as legumes.

(Mimosaceae/ Acacia, Albizia, Calliandra, Mimosa

Caesalpiniaceae/ Bauhinia, Cassia, Cercis, Delonix (poinciana)

Fabaceae) Clianthus, Erythrina (coral tree), Genista (broom), Hardenbergia , Laburnum, (sweet pea), (lupin) Medicago (, lucerne), Phaseolus (bean), Pisum (pea), Robinia , Trifolium (), Ulex (gorse), Virgilia, Wisteria

Magnoliaceae Liriodendron (tulip tree), Magnolia, Michelia

Malvaceae Abutilon, Gossypium (cotton),

Moraceae Ficus (fig), Morus (mulberry)

Myrtaceae Agonis, Angophora, Astartea, Beaufortia, Callistemon, Calytrix, Calothamnus, Chamaelaucium, Eucalyptus, Eugenia, Feijoa, Kunzea, Leptospermum, Lophostemon, Melaleuca, Metrosideros, Micromyrtus, Thryptomene, Tristania, Tristaniopsis, Myrtus, Xanthostemon Nyctaginaceae Bougainvillea, Mirabilis

Oleaceae Forsythia, Fraxinus (ash), Jasminum (jasmine), Ligustrum (privet), Olea (olive), Osmanthus, Syringia (lilac)

Pittosporaceae Billardiera, Hymenosporum. Pittosporum, Sollya

Plumbaginaceae Armeria (thrift), Ceratostigma , (statice), Plumbago

Primulaceae , Primula

Proteaceae Banksia, Conospermum, Dryandra, Grevillea, Hakea, Isopogon, Macadamia, Protea, Stenocarpus, Telopea (waratah)

Ranunculaceae Anemone, , , Delphinium, Helleborus, Paeonia, Pulsatilla, .

Rubiaceae Coffea (coffee), Coprosma, Gardenia, Ixora, Luculia, Pentas

Rutaceae Boronia, Citrus, Coleonema (diosma), Correa, Crowea, Eriostemon, Murraya Rosaceae Chaenomeles (flowering quince), Cotoneaster, Crataegus (hawthorn), Cydonia (quince ), Fragaria (), Geum, Kerria, Malus (), Prunus (almond, apricot, cherry, peach, ), Pyracantha (firethorn), Pyrus (), Rosa (rose), Rubus (raspberry, ), Sorbus (rowan), Spiraea

Saxifragaceae Astilbe, Bergenia, Deutzia, Hydrangea, Philadelphus,

Scrophulariaceae Antirrhinum (snapdragon), Calceolaria, (foxglove), Hebe, Linaria, Nemesia, , Russelia, ,

Solanaceae Browallia, Brugmansia, Capsicum, Cestrum, , Lycopersicon (), Nicotiana (tobacco), Petunia, (, /aubergine) Theaceae Camellia, Gordonia

Verbenaceae , Duranta, Petrea, ,

Vitaceae Cissus, Parthenocissus (Virginia creeper, Boston ivy), Vitis () 8

Monocotyledons Agavaceae ,

Amaryllidaceae , Anigozanthus (kangaroo paw), Clivea, , (daffodil, jonquil),

Araceae Acorus, Alocasia, Anthurium, Arum, Caladium, Calla, , Monstera, Philodendron,

Arecaceae Palms: Acanthopheonix, Archontophoenix, Caryota, Chamaedorea, Cocos, Howea, Livistona, Phoenix, Rhapis, Sabal, Trachycarpus, Washingtonia

Bromeliaceae Bromeliads

Cyperaceae (sedge) , (papyrus)

Poaceae The grasses, corn, , (Graminae) Crocus, Dietes, Dierama, Freesia, , Ixia, Sparaxis, Watsonia

Liliaceae (, , garlic, ), , Chlorophytum, Crocus, Hemerocallis, Hyacinth, Dracaena, Kniphofia (red hot poker), Lachenalia, , Liriope. Tulipa, (grass tree)

Marantaceae Calathea, Ctenanthe,

Orchidaceae Orchids: Brassia, Calanthe, Cattleya, Cymbidium, Dendrobium, Epidendrum, Oncidium, Phalaneopis, Spathoglottis, Vanda

The Cymbidium orchid is a The Camellia is a dicotyledon monoctyledon

SELF ASSESSMENT Perform the self assessment test titled ‘Self Assessment Test 1.3’. If you find yourself getting the answers wrong, revise the notes from this lesson and repeat the test.

9 PLANT GROWTH AND LIFE CYCLES

The life cycle of a plant indicates how long a plant takes to grow, flower and set seed.

Plant Life Cycles

Annual plants complete their entire life cycle in one season. This is why they are called annuals - they grow, flower, set seed and die in one year.

Biennial plants are similar, except their life span carries over two consecutive growing seasons. They grow leaves and other vegetative parts in one season then become dormant during the non- growing season. In the following growing season, they flower, set seed and die.

Perennial plants live for longer than three years. They can grow, flower and set seed many times over. In the case of many herbaceous perennials, the plant may re-grow new stems. The stems of woody perennials may live for many years, as tree trunks do.

Ephemeral plants survive for only a few weeks and may complete several life cycles in one season.

Stages of Plant Development Plants have 5 distinct phases of development during their life cycle:

1. Embryonic growth (seed) – the growth and development of the seed within the parent plant and the seeds subsequent germination. 2. Juvenile (vegetative) stage – following germination the plant increases in size as the cells enlarge and differentiate to form stems, leaves and . In many woody plants, this stage is characterised by the plant’s inability to form flowers. Cuttings taken from plants in the juvenile phase have a high ability to form adventitious roots (a root that growths from places other than the primary root). Some plants have markedly different foliage during the juvenile phase. 3. Adult mature (reproductive) stage – this phase is marked by the formation and development of the sexual organs – the flower buds, flowers, fruit and seed. Cuttings taken from plants in the mature phase have a reduced (or no) ability to form adventitious roots. 4. Senescence – the decline of the plant due to physiological change (due to the decline of cell division and ) or environmental stress or pathogenic (disease) attack. 5. Death.

Plant phase changes have implications for horticulturists. Plant propagators need to keep stock plants in the juvenile phase for as long as possible, so that cuttings taken from the plants will form roots easily. Plant breeders need mature flowering plants so they can see the results of their breeding programs.

MORPHOLOGICAL CHANGES DUE TO MATURATION

As a plant matures, many changes occur to the plant’s appearance. The following morphological characteristics alter during the various phases of maturation:

• Cuticle becomes thicker on leaves. • may peel or split off. • Leaf shape and thickness may change - heterophylly is where younger leaves are different shapes to the mature leaves. • Phyllotaxis - the arrangement of leaves along the stem. Many plants vary this feature as the plant grows and matures.

10 • Thorniness and orientation – e.g. thorns on juvenile citrus become more upright as the plant matures. • Branch number and pattern may alter. • Shoot growth and vigour - some plants are very vigorous when they are in the juvenile phase but are less vigorous when mature or reproductive. • Seasonal leaf retention and pigmentation, e.g. beeches – the top branches lose leaves while juvenile lower leaves are retained. • Ability to form adventitious roots and buds often decreases. • Partitioning of photosynthesis. • Cold resistance - young may not have good cold tolerance.

TERMINOLOGY

Learn the following definitions:

In relation to annuals: • Half hardy: Indicates plants that will tolerate local conditions with a certain amount of protection.

• Hardy: Plants adapted to cold temperatures or other adverse climatic conditions of an area.

In relation to perennials: • Tender: It means not hardy, i.e. not winter-hardy; the plant in question does not survive winter temperatures – this plant should be thought of as an annual.

• Half hardy: Indicates plants that will tolerate local conditions with a certain amount of protection.

• Hardy: Plants adapted to cold temperatures or other adverse climatic conditions of an area.

SELF ASSESSMENT Perform the self assessment test titled ‘Self Assessment Test 1.4’. If you find yourself getting the answers wrong, revise the notes from this lesson and repeat the test.

PLANT REVIEW WORKSHEETS

With each assignment you will be required to prepare 7 plant review and identification sheets (there should be two plants per sheet) making 14 plants in total per assignment .

When you submit your first assignment, submit your first plant identification sheets at the same time and then submit 7 sheets along with each of your following assignments.

Each plant should be named, described and illustrated.

Naming the Plant Include the common name, scientific name; and the plant family name if possible. If you cannot provide one of these, write a note to the tutor explaining that you attempted to find the information and why you could not.

11 Your tutor will often be able to help at least partly identify the odd unidentified plant; if you submit an illustration and good description (ideally presenting not only a leaf, but also a flower, fruit or seed head),

12 Describing the Plant You should record information that might be important to selecting and using this plant for in horticulture:

• Height: how high can it grow in your locality? • Width: how wide can it grow in your locality? • Flowers: what colour and when does it flower? • Leaf colour, shape, texture: what colour are the leaves when young and when mature? Are the leaves round, feathery, lobed or spiky? Are the leaves fine or coarse textured? • Scent: are the flowers scented? • Animal Attraction: does the plant attract birds, butterflies, bees? If so what part of the plant (flower or fruit)? • Hardiness: is it frost tender? How does the wind affect it? Does it prefer shade or sun? • Culture: are there any special things the plant requires? How hard should it be pruned and how often? Does it need good drainage? How often should it be fertilised? etc. • Pests and Diseases: list any pests and diseases that are particularly bad for this plant. • Maintenance: are there any maintenance requirements for the plant such as pruning or raking fallen leaves in winter?

These descriptions need not be comprehensive. Apart from the plant name, write only 50 to 100 words to describe each plant.

Illustrating the Plant This may be done any of the following ways: a) Submit a photograph or drawing of parts of the plant. b) Send a scan of a photograph or drawing (do not send large graphics files over the internet. Consult your student manual for details). c) Refer to a web site page location where you have found the plant illustrated on the internet. d) Submit a photograph of a pressed specimen (Note : do not send pressed specimens across state or national boarders. To do so may be illegal and in breach of quarantine regulations).

The following website contains a plant directory you can access this site on www.acsgarden.com there are many more sites that also have plant directories you might use.

The followings garden ezine is another valuable resource for both general, and topic specific horticultural information. We suggest you use it frequently. See www.acsgarden.com

A PRESSED PLANT COLLECTION CAN HELP You may decide to also collect and press specimens of plants.

While it is both difficult and may be illegal to send plants to us through the post (due to quarantine regulations); it can be a useful exercise for you to collect and label pressed specimens of plants.

(Note: this is not a compulsory task).

It is a well recognised fact (by most horticultural professionals) that the more you handle plants, the more you are able to identify them.

Plant specimens consisting of a few leaves and perhaps a flower or fruit can be preserved for hundreds of years by a simple technique known as pressing. There are many ways of pressing a plant as outlined below (some being more permanent than others). All basically involved the same general procedure: a) The plant specimen is laid out flat on a sheet of absorbent material such as newspaper.

13 b) A second sheet is placed on top of the plant. c) The plant sandwiched between these two sheets is then placed in a situation where pressure can be applied squeezing all the liquid from the plant tissue (e.g. placed between or in heavy books such as phone books, or placed in a plant press). d) Changing the paper frequently will speed up the drying process, and help reduce the likelihood of your specimens going mouldy. e) After a period of time anything from a week to several months, the plant can be removed and attached to a sheet of paper or card (i.e. mounted). f) The mounted specimen should be stored in a dry situation if it is to be preserved for any length of time. g) If you have problems pressing your plants, or would like further information contact the school and ask us to send out a copy of the booklet 'Pressing Plants'.

14 EXAMPLE OF A PLANT IDENTIFICATION WORKSHEET Plant No. 1. Sketch Or Photo Plant Family......

Genus ......

Species......

Common Name......

How and Where to Plant it......

Height...... Spacing......

Hardiness ......

Appearance ……......

Uses ……......

Culture ......

Pest and Disease ......

Plant No. 2. Sketch Or Photo Plant Family......

Species......

Genus......

Common Name......

How & Where to Plant it......

Height...... Spacing......

Hardiness ......

Appearance ……......

Uses ……......

Culture ......

Pest and Disease ......

NOTE: This is a sample only! Change the format to suit your situation - but make sure you include all the details asked of you. 15

SET TASK 1. Research the definition of the following botanical terms - take notes: • Annual • Biennial • • Ephemeral • • Fruit • Herbaceous • Lignification • Perennial, woody perennial • Semi-deciduous • Semi-evergreen • • Tree

2. Now do some research into the horticultural (rather than botanical) meaning of the terms annual, biennial, perennial. Example some plants are treated differently in horticulture than they are botanically i.e. perennial plant treated as an annual or a biennial; or biennial treated as an annual – why is this done?

3. Draw two diagrams (one of a , the other a dicotyledon), showing the external differences between a monocotyledon and a dicotyledon.

ASSIGNMENT Download and do the assignment called ‘Lesson 1 Assignment’.

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