1. Section 6 Dendrology: The Scientific Study of Trees

2. Chapter 19 Classification and Anatomy of Trees

3. Dendrology The scientific study of trees is known as Dendrology
Anatomy: study that examines structure of an organism
Arrangement and relationship of organs/parts to other organs
Physiology: the branch of biology that deals with the life functions and processes of living organisms

6. Tissue Systems of Tree Tissue systems perform specialized functions
Ground tissue system: much of material in plant leaves, roots, stems, fruit
Vascular tissue system: moves nutrients
Dermal tissue system: protects against loss of fluids
Meristem tissue: rapidly dividing, causes plants to grow

7. Tissue Systems of Tree (Continued)
Organ: several tissues that function as single unit
Vegetative organs
Reproductive organs

8. Vascular Tissue
Xylem: water-conducting woody tissue carrying nutrients from roots to stems to leaves
Important components of xylem:
Tracheids and vessel elements, once they become dead and hollow
End-to-end vessels: more efficient than tracheids
Vessel element: A hollow tube where nutrients pass

10. Vascular Tissue (Continued)
Phloem: vascular tissue located in the interior layer bark, stems and roots.
Sugars flow from high concentration to low concentration

11. Annular Rings
Annular Rings consist of new later of woodt xylem tissue that has been deposited each year. (determine age, conditions, weather)
Spring wood
Often a smaller darker ring
Summer wood
Larger and lighter color
More favorable
growing season

13. Dendrochronology

14. How old is this tree? (Core 1)
6. How do the banding patterns of the two cores compare?

17. Cambium-located between the phloem and xylem that contains a dividing mass of cells.
Vascular Ray-transport dissolved materials across the woody section (xylem) between the phloem and the pith.
Pith- is located in the center of the stem and primarily stores plant food.
Heartwood- older xylem filled with tannins bums and resins, which becomes darker in color and no longer conducts water.
Sapwood-lighter colored wood through which water still moves.

18. Dermal Tissue System
Dermal tissues protect plants from loss of fluids and keep harmful microorganisms out of the cells
Epidermis: protective outer layer of cells of leaves, stems, flowers, seeds, and roots
Cuticle: The waxy material covering plants

19. Plant Tissues

20. Dermal Tissue (Continued)
Meristem: rapidly dividing mass of cells that causes plants to grow
Apical meristems: at ends of branches, twigs, roots
Cambium layer: between phloem and xylem layers of roots and stems
When a cell in the cambium divides one cell remains until it divides again. The other cell becomes part of the xylem or phloem tissue.
Cell division increases diameter of stem or root (Xylem)
Forms vascular rays that transport materials across woody section of stem

21. External Parts of Tree Leaf
Petiole: point of attachment to tree
Vascular tissues for transporting nutrients to leaf cells
Blade
Midrib: gives shape, distributes nutrients
Spines: function like midrib
Veins: distribute material to and from leaf cells
Margin: useful for tree identification

24. Taproots and Fibrous Roots
Trees have either a taproot system or a fibrous root system
A taproot system has a primary root that grows much larger and deeper than the other roots
A fibrous root system does not have a large dominant root
Primary root branches out just below the soil surface and the main roots are near the same size

25. Taproots and Fibrous Roots (Continued)
Many trees have taproots during the seedling stage, but in some species, the taproot gives way to a fibrous root system as the tree matures

26. Root Systems

27. Anatomy of Tree Root
Plant roots: specialized organs that anchor trees in soil and transport nutrients and water into plant
Fungi that attach to a plant’s roots, dissolve nutrients making it available to the plant
Epidermis: protects root, absorbs water and nutrients, includes root hairs
Root hairs- increase surface area for water and minerals absorption.

28. Secondary Root Tissues
Secondary tissues develop from meristem tissue, or vascular cambium, and provide secondary growth
Secondary xylem and secondary phloem add thickness

29. Basic Parts of Flower Female flower parts constitute pistil
Stigma: pollen receptor
Ovary: produces egg cell; seed forms in ovule
Style: connects stigma to ovary
Male flower parts compose stamen
Anther: pollen grains develop here

30. Basic Parts of Flower (Continued)
Filament: connects anther to receptacle or base of flower
Petals: color attracts pollinators
Sepals: leaflike, protects flower

31. Anatomy of a Flower

32. Perfect (bisexual flowers)- Containing both male and female reproductive flowering parts.
Imperfect Flowers- Some broad leaf trees are unisexual male (staminate) and female (pistillate) Flowers.
These may be born on the same plant like oaks and hickories or on separate trees as in hollies. A few trees have both perfect and imperfect flowers intermixed

33. Tree Types Gymnosperms bear seeds in cones
Pines, spruces, cedars
Slow movement of dissolved plant materials through tracheid cells
Angiosperms produce seeds inside ovary, or fruit
Plant materials transported rapidly through tracheid and vessel elements