Plant Taxonomy

1. Plant Taxonomy Scientific Classification of Plants By: Stephen Edwards, Johnny Jessup & Scott Robison Agriculture Teachers/FFA Advisors

2. Goals • Define Plant Taxonomy • Discover why plants are classified through the binomial naming system • Order plants in each of the classification sections

3. What Is Taxonomy? • Taxonomy is the science of classifying and identifying plants using scientific names

4. Why Use Scientific Names? • Scientific names are necessary because • Same common name are used for two different plants • More than one common name are used for the same plant • Sweetgum or Liquidamber?

5. Carolus Linnaeus • Swedish botanist Karl von Linne came up with the idea in the mid-18th century with a system that would give each species of plant its own name • His system is called the binomial system

6. Binomial System • The system uses two words for the full name • The system is based on the Latin language, since Latin is the language that is used worldwide by scientists • To propose his new idea, Linne changed his name to its Latin form, Carolus Linnaeus

7. Genus • In the scientific name, the first name is the genus • All plants in the same genus have the same type of reproductive structures • The genus is always capitalized • Examples of genera • Cornus – dogwood Acer - maple • Quercus – oak Ilex – holly • Magnolia - magnolia

8. Species • The second word, when combined with the first word is the species • Species are able to reproduce sexually to end up with the same characteristics in their offspring • The second word is usually descriptive of the plant in some type • The second word, or specific epithet is always lower case

9. Examples of Specific Epithets • Large showy flowers – grandiflora • Red – rubrum • White - alba • Flowering – florida • From Japan - japonicum • From America – americana • Dwarf- nana

10. Quick Review • Using your previous notes what are the common names of the following species • 1. Acer rubrum • 2. Quercus alba • 3. Cornus florida • 4. Magnolia grandiflora

11. Variety or Cultivar • Variety is a variation of a plant that is found in nature and that can be reproduced through sexual propagation • Cultivar is a “cultivated variety” and cultivated by man for a specific reason. They are usually asexually propagated

12. Writing Varieties • Varieties are written with a var. Following the species name, then the variety. Varieties are italicized • Sanseveria trifasciata var. Laurentii

13. Writing Cultivars • Cultivars are written in single quotes following a species name. They are not italicized • Ficus elastica ‘Decora’ • Cultivar= cv.

14. Plant Hierarchy • Plant classification can be broken down in the plant hierarchy system • All plants, from one cell organisms to the tallest trees are in the plant kingdom • All members of the plant kingdom are autotrophs, meaning that they can produce their own food. Plants do this through photosynthesis

15. Plant Hierarchy General • Kingdom • Division • Classes • Orders • Families • Genera • Species Specific

16. Plant Divisions • The Plant Kingdom is broken down into many divisions. The four most important are • Thallophytes • Bryophytes • Pteriophytes • Spermatophytes

17. Thallophytes • No true stems, leaves, or roots • Either one cell or a mass of cells. No form/function • Examples include Algae and Lichens

18. Bryophytes • Lack a vascular system for the transportation of water • Examples include Mosses and Liverworts

19. Pteriophytes • Non-seed vascular plants • These plants reproduce through spores, not seeds • Examples include ferns and club mosses

20. Spermatophytes • The Spermatophyte Division is the division that we work the most with in Horticulture • These plants produce seeds • This division is divided into two sub-divisions • Gymnosperms • Angiosperms

21. Gymnosperms • Cone Bearing Plants

22. Angiosperms • Fruit Producing Plants

23. Subdivision Angiosperms • Angiosperms are divided into two classes • Monocotyledon • Dicotyledonous

24. Monocotyledon • One-seed leaves • Examples include Lilies, Palms, Corn, and Grass

25. Dicotyledon • Two seed leaves • Examples include most of the broadleaf plants

26. Class Breakdown • Classes are broken into Orders • Orders are broken into Families • Families are broken into Genera • Genera are broken into Species • Species can be broken into varieties or cultivars

27. Kingdom Division Classes Orders Families Genera Species Plant Spermatophyte Magnoliopsida Rosales Fabaceae Cercis Cercis canadensis Example of a Class Breakdown - Redbud

28. Cercis canadensis - Redbud

29. Plant Characteristics

30. Identifying Plants • Physical characteristics are used to identify plants which include…. • Life Cycle • Form • Foliage Retention • Plant Parts • Use & Location

31. Life Cycle • Annuals • Plants that complete their life cycle in one year. • Biennials • Plants that complete their life cycle in two years. • Perennials • Plants that live more than two years.

32. Growth Habits • Trees • 20’ or taller • Shrubs • Less than 20’ • Vines

33. Columnar Spreading Weeping Round Oval Pyramidal Growth Forms

34. Spreading Columnar Weeping Growth Forms

35. Round Pyramidal Oval Growth Forms

36. Foliage Retention • Deciduous • Loses leaves during the dormant season. • Not necessarily winter, may be summer for some plants • Evergreen • Keeps leaves and remains green year-round.

37. Deciduous vs. Evergreen

38. Plant Parts – Leaf • Arrangement • Shapes • Color • Vein Pattern • Form – Simple or Compound • Margin • Surface

39. Leaf Arrangement – Simple

40. Leaf Arrangement – Compound

41. Leaf Shape

42. Vein Pattern • Pinnate • Palmate • Parallel • Dichotomous

43. Leaf Margin

44. Glabrous Pubescent Villous Tomentose Scabrous Glaucous Rugose Glandular Leaf Surface • There are 8 common leaf surfaces.

45. Leaf Surface – Glabrous • The surface is smooth, not hairy.

46. Leaf Surface – Pubescent • Short, soft hairs cover the surface.

47. Leaf Surface – Villous • Long, straight hairs cover the surface.

48. Leaf Surface – Tomentose • Covered with wool-like hair.

49. Leaf Surface – Scabrous • Covered with short, prickly hairs.

50. Leaf Surface – Glaucous • Covered with a bluish-white waxy substance.