R2101 - Plant classification Flashcards
Know the characteristics and the naming of the main groups of plants and their life cycles.
1.1 What is a conifer?
- Mostly evergreen
- Perennial woody plants with secondary growth
- Cones and naked seeds
- Needle-shaped or scalelike leaves
1.1 Name 2 examples of a conifers
Pinus spp. (Pines)
Cupressus spp. (Cypresses)
1.1 What are the characteristics of a flowering plant?
- Evergreen and deciduous
- Herbaceous and woody
- Flowers and enclosed seeds
- All life cycles.
1.1 Describe a Monocotyledon or Monocot.
Seed - has one cotyledon (part of the embryo within seeds that form the first leaves when the plant germinates)
Roots - Fibrous roots ( thin, moderately branching roots growing from the stem)
Stem - Vascular bundles carrying water and nutrients up and down the stems are scattered randomly
Leaves - Long narrow leaves with parallel veins
Flowers - Floral parts in multiples of 3
1.1 Describe a Dicotyledon or Dicot.
Seed - has two cotyledons (part of the embryo within seeds that form the first leaves when the plant germinates)
Root - tap roots ( a long straight tapering root growing vertically downwards and forming the centre from which subsidiary rootlets grow)
Stem - the vascular bundles that carry water and nutrients up and down the stems are arranged in a neat ring
Leaves - broad leaves with veins forming a network
Flowers - floral parts in multiples of 4 or 5
1.2 Why are botanical plant names important?
- Stability over time
- Common names are different from place to place, change over time and are often ambiguous
- Uniqueness to a species
- Internationally understood, allowing plant identification and communication
1.2 What does genus (genera plural) mean?
- A group of individuals within a family which have characteristics in common
1.2 What does species mean?
- Basic unit of classification
- Group of individuals with the greatest mutual resemblance
- Abilty to breed amongst each other
1.2 Describe the binomial system of naming plants.
- Binomial means two names.
- First part GENUS (plural genera)
- Second part specific name, and refers to the SPECIES
- There may be one species in a genus or hundreds
1.2 How are binomial names written?
Using an italic script, with the Genus name given a capital letter, the specific name is NEVER given a capital letter.
1.2 Give 3 examples of binomial names.
- Myosotis sylvatica
- Cyclamen coum
- Fatsia japonica
1.2 What is a cultivar?
A selection made from a species and propagated vegetatively (not by seed) so that every individual is identical.
1.2 How are cultivars written?
Cultivar names come after the Genus and species and are enclosed within ‘inverted commas’ and written in regular script.
1.2 Give 3 examples of cultivar names.
- Nigella damascena ‘Miss Jekyll’
- Cosmos bipinnatus ‘Rubenza’
- Hedera helix ‘White Ripple’
1.3 What are the 5 stages in the life cycle of a plant?
- seed
- juvenile
- adult
- senescence
- death
1.3 Describe the seed stage.
- Germination occurs at correct temperature, when enough water and oxygen are present (some seeds also require light)
- a root grows downwards to access water
- shoots grow upwards above ground to harvest energy from the sun
- leaves form
1.3 Describe the juvenile stage.
- plant increases in size as cells enlarge and differentiate to form roots, stems and leaves
- in some plants leaves are larger and different in shape to the adult plant
- non-reproductive stage; no flowers, fruit or seeds
1.3 Describe the adult stage.
Reproductive phase where the plant produces flowers, fruit and seeds.
1.3 Describe the senescence stage.
- follows maturity as plant growth deteriorates
- herbaceous perennial occurs in above ground growth
- annuals the entire plant
1.3 Describe the death stage.
- annual’s life cycle is over in one season ending in death
- perennial’s roots survive through winter
1.3 Name some reasons why life cycles of plants are significant to horticulture.
- Understanding what to plant and when; so the desired growth is reached at the preferred time
- When lifecycles are understood they can be manipulated to produce new plants at a desired stage. E.g. juvenile round leaved growth of eucalyptus is desirable to the floristry industry so it’s coppiced to produce a continual output of juvenile growth
- Fundamental for planning planting schemes
- Cost effective - planting from seeds is much cheaper than mature plants
1.4 Define the botanical term annual with 2 examples.
A plant that completes its life cycle in one growing season
- Limnanthes douglasii
- Nigella damascena‘Miss Jekyll’
- Cosmos bipinnatus‘Rubenza’
1.4 Define the horticultural term annual with 2 examples.
In the horticultural world many naturally perennial plants may be grown as annuals and replaced after their first season of growth.
Pelargonium zonale Rudbeckia hirta ‘Cherry Brandy’
1.4 Define botanical the term biennial with two examples.
A plant with a life cycle that spans two growing seasons.
- Angelica* sylvestris
- Digitalis* purpurea
1.4 Define the horticultural term biennial with two examples.
In the horticultural world many naturally perennial plants may be grown as biennials and replaced after their second season of growth.
- Alcea rosea (Hollyhock)
- Erysimum cheiri (Wallflower)
1.4 Define the botanical term ephemeral with two examples. SV SM
A plant that has several life cycles in a growing season and can increase in numbers rapidly.
- Senecio vulgaris*
- Stellaria media*
1.4 Define the botanical term perennial with two examples.
A perennial is a plant that lives more than two years. The term is also widely used to distinguish plants with little or no woody growth (secondary growth in girth) from trees and shrubs.
Alchemilla mollis
Aster amellus ‘King George’
1.4 Define the horticultural term tender perennial with two examples.
A tender perennial is a perennial grown in a place where the winters are too cold survive outside, so they are brought indoors during the winter.
Gazania ‘Tiger Stripes’
Pelargonium‘Mabel Grey’
1.4 Define the horticultural term half hardy annual with two examples.
A half hardy annual is an annual sown under protection early in the season then planted out.
- Cosmos bipinnatus ‘Rubenza’
- Tropaeolum minus (Nasturtium)
1.4 Define the horticultural term hardy annual with two examples.
A hardy annual can survive some frosts and can be started from seed outside in spring, before the last frosts of the year.
- Calendula officinalis (pot marigold)
- Nigella damascena (love-in-a-mist)
1.4 Define the term shrub with two examples.
A woody plant generally smaller than a tree. Shrubs have multiple stems emerging from one base near ground level. They can be deciduous or evergreen.
- Buxus sempervirens
- Cornus alba ‘Bloodgood’
1.4 Define the term tree with two examples.
A tall woody plant with a single stem or trunk that branches at height. Trees can be deciduous or evergreen.
- Acer campestre
- Quercus robur
1.4 Define the botanical term herbaceous with two examples.
- lack persistent above ground growth
- do not form woody stems
- Annual: 1 year life cycle - Limnanthes douglasii
- Biennial: 2 year life cycle - Digitalis purpurea
- Perennial: Living for more than 2 years - typically dying back in autumn to ground level or underground resting buds, starting into growth again in spring - Alchemilla mollis
1.4 Define the botanical term woody with two examples.
- Divided into trees and shrubs
- Shoots are durable and survive over a period of years
- Deciduous and evergreen
- Quercus robur (oak tree)
- Buxus sempervirens (box shrub)
1.4 Define the botanical term evergreen with two examples.
- Retains leaves in all seasons
- Leaves of evergreens usually are thicker, darker green and more leathery than those of deciduous plants
- Hedera helix ‘Saint Agnes’
- Taxus baccata
1.4 Define the botanical term semi-evergreen with two examples.
A plant that retains some of its leaves through the year but may shed most leaves under severe weather conditions such as extreme cold or drought.
- Lonicera japonica ‘Mint Crisp’
- Dryopteris cycadina
1.4 Define the botanical term deciduous
A plant that sheds all of its leaves at once, often at the end of the growing season.
- Acer campestre
- Quercus robur
