HortBotany
Lesson Plan 2
Classification & Nomenclature
References: Acquaah: Horticulture; Principles and Practices
Schooley: Introduction to Botany
KINGDOM
PHYLLUM or DIVISION (-phyta)
CLASS (-opsida)
ORDER (-ales)
FAMILY (-aceae)
GENUS
SPECIES
VARIETY/
CULTIVAR
The Evolution of Taxonomic Schemes
Linnaeus
1735
2 kingdoms
Haeckel
1866[1]
3 kingdoms
Chatton
1937[3]
2 empires
Prokaryota
(not treated)
Copeland
1956[5]
4 kingdoms
Monera
Whittaker
1969[7]
5 kingdoms
Woese et al.
1977[8]
6 kingdoms
Woese et al.
1990[9]
3 domains
Eubacteria
Bacteria
Archaebacteria
Archaea
Monera
Protista
Protista
Protista
Fungi
Fungi
Plantae
Plantae
Plantae
Animalia
Animalia
Animalia
Protista
Vegetabilia
Animalia
Plantae
Animalia
Eukaryota
Eukarya
-2-A popular scheme (Whittaker, 1969) includes 5 kingdoms:
Kingdom Monera:
* comprised of bacteria. Bacteria are small, unicellular
organisms.
*prokaryotes; cells have no membrane around the
nucleus and no distinct organelles.
*heterotrophic or autotrophic.
*bacteria are the most numerous of any
living organisms.
*bacteria species are incredibly diverse; inhabiting hot
sulfur springs, glacial ice, and the ocean floor.
*bacteria are the most ancient of all organisms.
*many bacteria, like E. coli and Salmonella, cause
diseases. Others are harmless and several perform
useful functions.
Kingdom Protista:
*unicellular, multicellular, or colonial.
*eukaryotes; cells have a membrane around the nucleus
and distinct membrane-bound organelles.
*heterotrophic or autotrophic.
*essentially a home for the “left-over” organisms that
couldn’t be classified elsewhere.
*this kingdom includes:
a) many algae.
b) slime molds.
c) protozoa.
d) sponges.
*organisms as diverse as giant sea kelp and amoebas
fall into this kingdom.
Kingdom Fungi:
*filamentous eukaryotes.
*heterotrophic.
*many important plant diseases are caused by fungi.
*many feed on dead and decaying organisms.
Kingdom Plantae:
*multi-cellular eukaryotes.
*autotrophic organisms that can photosynthesize.
*photosynthesis is the ultimate source of virtually all the
earth’s oxygen.
Kingdom Animalia:
*multi-cellular eukaryotes.
*heterotrophic organisms that ingest their food.
*includes everything from insects, to frogs, to humans!
-3-
Some terminology to know:
Any organism like a plant, a person, or bacteria for example can be referred
to as being a prokaryote or eukaryote. The definitions follow…
Prokaryotes: primitive organisms, usually consisting of a single cell, which
has no membrane-bound nucleus and no distinct cellular organelles. Bacteria
are prokaryotes.
Eukaryotes: single or multicellular organisms whose cells have a distinct,
membrane-bound nucleus and distinct cellular organelles. Organisms in the
Kingdom Protista, fungi, plants, animals and people are eukaryotes.
Autotrophic: any organism that can manufacture it’s own food is said to be
autotrophic. For example, plants can make sugars from carbon dioxide and
water using a process called photosynthesis. Plants are autotrophic.
Heterotrophic: any organism that requires organic substrates to get its
carbon for growth and development. In other words these are organisms that
have to eat or “absorb” other organisms to survive. All animals are
heterotrophic, as well as fungi and many bacteria.
Vascular Plants: are plants that have xylem and phloem. Xylem is the water
conducting tissue in plants and phloem is the food (sugar) conducting tissue in
plants.
Non-vascular Plants: are plants like the Liverworts and Mosses, which lack
vascular tissue.
Seed Producing Plants: are plants in the Angiosperm and Gymnosperm
divisions that produce true seeds.
Non-seed Producing Plants: are plants like the Club Mosses, Horsetails and
Ferns that propagate themselves by spores rather than seed.
-4- What follows is the complete classification of Spiraea nipponica
‘Snowmound’, commonly known as Snowmound Spiraea:
Kingdom:
Division:
Class:
Order:
Family:
Genus:
Specific Epithet:
Species:
Cultivar:
Plantae
Magnoliophyta
Magnoliopsida (Dicots)
Rosales
Rosaceae
Spiraea
nipponica
Spiraea nipponica
‘Snowmound’
The need for learning scientific names:
1) The present system of scientific nomenclature is not perfect and is
constantly revised.
2) A species of plant may have many common names, but it will have only one
scientific name. Common names can vary from one region of the country
to the next.
3) Scientific names are universal and are recognized around the world. Many
horticultural products are listed and sold only by their scientific names.
4) Consider the species Euonymus europaeus which is also known by the
following common names:
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
Arrow-beam
Prick-timber
Prickwood
Cat-tree
Pegwood
Pincushion-shrub
Shiver-wood
Witchwood
Louseberry
Butcher’s prick tree
Gatten tree
Spindle tree
-5-
5) Also, consider the confusion over the tree commonly known as Red maple.
Red maple is the species Acer rubrum; a tree having green leaves that turn
red in the fall. Many people mistakenly believe Red maple has red leaves
and confuse the plant with the red-leafed cultivar of Norway maple called
‘Crimson King’ (Acer plantanoides ‘Crimson King’).
6) Learning scientific names, while more challenging at first, will pay off in
the long run.
The Species
 Probably the most important and most useful level of classification.
 A 3 part definition:
1) A group of organisms.
2) Sharing a set of common traits or characteristics.
3) That are inheritable (can be passed down from one generation to
the next).
-6-
Alternative Way of Classifying Plants
Classification based upon duration or longevity:
http://extension.oregonstate.edu/mg/botany/index.html
1) annuals: survive for a single growing season (cereal grains, annual
flowers).
a) seed germination.
b) plant growth.
c) flowering.
d) fruit and seed production.
e) plant death.
2) biennials: survive for 2 growing seasons (beets, celery, cabbage, carrots,
and turnips).
First growing season:
a) seed germination.
b) plant growth.
c) plant survives the winter as an underground stem or root.
Second growing season:
a) plant produces new stems and leaves.
b) flowering.
c) fruit and seed production.
d) plant death.
-7-
3) perennials: survive for 3 or more growing seasons.
a) seed germination.
b) plant growth.
c) woody perennials (trees and shrubs) stop growing in late summer, store
food in their roots and stems, and produce buds to survive the winter.
d) herbaceous perennials (Hostas, Daylilies, Bleeding Heart, etc.) do not
have a persistent woody stem. Their stems and leaves die back every
fall. The plant survives the winter as an underground root or stem. In
the spring, when conditions are favorable for growth, new stems and
leaves are produced.
e) both woody and herbaceous perennials will flower when they reach the
adult phase of growth. Most herbaceous perennial plants can reach the
adult growth phase and flower in one growing season. However, trees
may take many years before they reach the adult phase and flower.
After flowering, perennial plants produce fruit containing seed.
f) perennial plants survive for many growing seasons (some trees get to be
hundreds of years old).
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