Today’s Agenda
                                                                                                                            ◦ History of Plant Taxonomy
                                                                                                                            ◦ Plant Classification
                                                                                                                            ◦ Scientific Names
                                                                                                                            ◦ Leaf and Flower Characteristics
                                                                                                                            ◦ Dichotomous Keys
                     Plant Identification
                     Heather Stoven
                        What do you gain                                                                                     Looking at plants more closely
                        from identifying 
                        plants?  Why is it                                                                                   ◦ How do plants relate to each other?  How are they 
                        important?                                                                                             grouped?
                         •  Common disease and 
                            insect problems
                         •  Cultural requirements
                         •  Plant habit
                         •  Propagation methods
                         •  Use for food and 
                            medicine
                          Plant Classification                                                                               Plant Classification
                           Group each plant into a specific category                                                              Group each plant into a specific category
                                       Maple                      Spiraea                                                                      Maple                  Spiraea
                                    Viburnum                    Crabapple                                                                   Viburnum                 Crabapple
                                    Apple tree                      Ash                                                                     Apple tree                   Ash
                                      Daylily                   Geranium                                                                      Daylily                Geranium
                                      Tomato                     Poinsettia                                                                   Tomato                 Poinsettia       TREES
                                        Oak                       Pepper                                                                        Oak                    Pepper
                                 Weeping willow                     Mint                                                                 Weeping willow                 Mint
                                      Petunia                   Euonymus                                                                      Petunia                Euonymus
                                                                                                                                                    OS-Plant ID.ppt, page 1
                     Plant Classification                                                          Plant Classification
                         Group each plant into a specific category                                      Group each plant into a specific category
                                   Maple              Spiraea                                                     Maple             Spiraea
                                 Viburnum           Crabapple     Ornamental                                    Viburnum           Crabapple
                                 Apple tree            Ash                                                      Apple tree            Ash         Edible
                                  Daylily           Geranium       Flowering                                     Daylily           Geranium
                                  Tomato             Poinsettia       Plants                                     Tomato            Poinsettia     Crops
                                    Oak               Pepper                                                       Oak               Pepper
                              Weeping willow           Mint                                                  Weeping willow           Mint
                                  Petunia           Euonymus                                                     Petunia           Euonymus
                                                                                                   Carolus Linnaeus
                     Plant Taxonomy                                                                The Father of Taxonomy
                    ◦ Identifying, classifying and assigning                                       ◦ Swedish botanist
                     scientific names to plants                                                    ◦ Developed binomial 
                    ◦ Historical botanists trace the start of                                        nomenclature
                     taxonomy to one of Aristotle’s students, 
                     Theophrastus (372-287 B.C.), but he didn’t                                    ◦ Cataloged plants based on 
                     create a scientific system                                                      natural relationships—primarily 
                    ◦ He relied on the common groupings of                                           flower structures (male and 
                     folklore combined with growth: tree,  shrub,                                    female sexual organs)
                     undershrub or herb                                                            ◦ Published Species Naturae in 
                    ◦ Detected the process of germination and                                        1735 and Species Plantarum in 
                     realized the importance of climate and soil                                     1753
                     to plants
                                                                                                                                     Photo: University of California at Berkley
                    ◦ Then, along came Linnaeus….
                    Plant Classification Pyramid                                               Generally Accepted Classification Units 
                    Kingdom                       Plantae                                      for horticulturists and gardeners
                    Monera, Protists, Fungi and Animals
                    Division (Phylum)
                    12: based mostly on reproductive                                               Family
                    characteristics (Angiospermae)
                    Family                                                                             Genus
                    Several hundred                                                                       Species
                    named
                    Genus
                    Species
                    An estimated 370,000 named
                                                                                                                      OS-Plant ID.ppt, page 2
                       Family                                                                                 Family names end in“aceae”
                       ◦ Group of closely related genera                                                       Caprifoliaceae–Honeysuckle family 
                       ◦ Similar structure and appearance                                                        including Honeysuckle, Snowberry, Weigela
                         ◦ Seed pod/fruit       Plants are classified based                                    Fabaceae–Pea family 
                         ◦ Flower parts         mainly on these characters
                         ◦ Leaf arrangement                                                                      including clover, Locust, mimosa, lupine
                                                                                                                 and vetch 
                       ◦ Cultural practices (i.e., the care of the                                             Oleaceae–Olive family
                        plant) generally follows family lines
                                                                                                                 including  Ash, Forsythia, and Privet
                       Remember our friend, Carl?                                                             What’s with the Latin?
                       ◦ Linnaeus simplified scientific names by                                              When Linnaeus published his first books
                        designating one Latin name to indicate the                                               oLatin was the language of science in Western Europe 
                        genus, and one as a "shorthand" name for the                                             oHe followed this trend using Latin and Greek names
                        specific epithet
                                                                                                               Spelling is universal, worldwide
                                          Binomial                                                                 o Pronunciation depends on 
                                  nomenclature!                                                                        local language and dialect
                        Scientific Names:                                                                    Scientific Names:
                        Binomial Nomenclature                                                                Binomial Nomenclature
                       ◦   The names are composed of two parts
                                                                                                             ◦ Species: the basis of the binomial system of 
                                       1. Genus                                                               nomenclature
                                       2. Specific epithet                                                   ◦ a difficult word to define, a population of 
                          Family: Bignoniaceae                                                                individuals within a genus that are capable of 
                                                                                                              interbreeding freely with one another
                                Catalpa speciosa
                                   Western Catalpa
                                Genus               Specific epithet
                                            Species
                                                                                                                                  OS-Plant ID.ppt, page 3
                        Genus and Species                                                                                       The specific epithet can give us 
                                                                                                                                hints plant about the plant:
                                                                                                                                ◦ Specific epithet: the second word in a scientific plant 
                                                                                                                                  name, not capitalized and usually an adjective used to 
                                                                                                                                  describe size, color, leaf shape, growth habit, origin of the 
                                                                                                                                  plant or to commemorate a person. 
                             Equus ferus                                    Equus africanus asinus                                 ◦ Cotoneaster horizontalis
                             caballus – 64                                  - 62 chromosomes                                       ◦ Coreopsis gigantea
                             chromosomes
                                                                                                                                   ◦ Clerodendrumthomsoniae
                                                                                                                                   ◦ Godetiagrandiflora
                                                                                                                                   ◦ Cistus x purpureus
                                                                                                                                   ◦ Chionanthusvirginicus
                                              Mules Equus asinus x Equus caballus – 63 
                                              chromosomes - sterile
                          Scientific Names:                                                                                       Participation question
                          Binomial Nomenclature                                                                                   Which name is written correctly?
                           ◦   Correct spelling                                                                                       Red maple:
                               •   Genus and specific epithet names are always 
                                   underlinedor in italics.
                               •   Genus is capitalized                                                                                   1. Acer rubrum 
                               •   Specific epithet is not                                                                                2. Acer Rubrum
                                   capitalized                                                                                            3. acer rubrum
                                         Fraxinus americana                                                                               4. Acer rubrum
                          Participation question                                                                                  Scientific Names:
                          Which name is written correctly?                                                                        Binomial Nomenclature
                              Red maple:                                                                                             ‘sp.’ = species (singular)                      Do not italicize 
                                                                                                                                     ‘spp.’ = species (plural)                       or underline.
                                  1. Acer rubrum
                                  2. Acer Rubrum                                                                                     For example
                                  3. acer rubrum                                                                                     ◦   Prunussp. –Refers to a definite plant in 
                                  4. Acer rubrum                                                                                         the Prunus genera of unidentified species.
                                                                                                                                     ◦   Prunus spp. –Refers to all of the species
                                                                                                                                         in the Prunus genus.
                                                                                                                                                           OS-Plant ID.ppt, page 4