Wood Anatomy Lecture V

Axial Cells Derived from Fusiform Initials of Angiosperm Cambium

I.  Vessel Elements
     A. Thick Walled
     B. Cylindrical, connected end to end
     C. Dead at maturity
     D. CW:lumen ratio -> smallest
     E. Bordered pits & perforation plates
     F. Primary function
          1. Transpiration of water & dissolved elements

II. Tracheids
     A. Thick Walled
     B. Elongate
     C. Dead at maturity
     D. CW:lumen ratio -> small
     E. Bordered pits
     F. Primary function
          1. Transpiration of water & dissolved elements
               in sapwood
          2. Waste storage in heartwood

III. Fiber-tracheids
     A. Thick Walled
     B. Elongate (can be septate)
     C. Dead at maturity
     D. CW:lumen ratio -> intermediate
     E. Small bordered pits with slit-like canal that extends
          beyond circular chamber 
     F. Primary function
          1. Transpiration of water & dissolved elements
               in sapwood
          2. Structural support
          3. Waste storage in heartwood

IV. Libriform Fibers
     A. Thick Walled
     B. Elongate (can be septate)
     C. Dead at maturity
     D. CW:lumen ratio -> large
     E. Slit pits  
     F. Primary function
          1. Structural support
          2. Waste storage in heartwood

V. Axial Parenchyma
     A. +-Thin Walled
     B. Rectangular with long vertical axis 
     C. Living cytoplasm at maturity
     D. CW:lumen ratio -> smallest
     E. Simple pits
     F. Primary function
          1. Food and/or waste storage
          
Ray Cells Derived from Ray Initials of Angiosperm Cambium

I. Ray Parenchyma
     A. +-Thin Walled
     B. Geometry
          1. Procumbent = rectangular longitudinal axis
               horizontally oriented in radial direction
          2. Marginal = rectangular longitudinal axis
               vertically oriented in radial direction 
     C. Living cytoplasm at maturity
     D. CW:lumen ratio -> smallest
     E. Simple pits
     F. Primary function
          1. Radial transport of water, elements, food
          2. Food and/or waste storage
Wood Anatomy Lecture VI

Variations in Angiosperm Wood Anatomical Characters of Taxonomic
Use

I.  Variation in vessel size within a growth ring
     A. Ring porous
     B. Semi-ring porous
     C. Diffuse porous

II. Pattern of vessel aggregation
     A. Exclusively solitary
     B. Radial groups of 4
     C. Radial or oblique
     D. Tangential arrangement
     E. Clusters

III. Perforation Plates
     A. Simple
     B. Multiple
     C. Number of scalariform bars

IV.  Pit and wall details of vessel elements
     A. Spiral thickenings
     B. Minute pits
     C. Opposite or scalariform pits
     D. Alternate pits
     E. Vestured pits

V. Vessel element lumen features
     A. Abundant tyloses
     B. Tyloses sclerosed
     C. Deposits or gum

VI. Metric features
     A. Number of vessels in transverse view
     B. Tangential diameter (not applied to ring porous)

VII. Other Dead Axial Cells
     A. Fibers
     B. Fiber-tracheids (Distinctly bordered fibers)
     C. Tracheids
     D. Spiral thickenings
     E. Septate

VIII. Axial Parenchyma Patterns
     A. Absent or rare
     B. Apotracheal
          1. Diffuse
          2. Diffuse-aggregate
          3. Concentric
     C. Paratracheal
          1. Scanty
          2. Vasicentric
          3. Aliform
          4. Aliform confluent
          5. Banded
               1. 1-seriate bands
               2. 2- to 4-seriate bands
               3. > 4-seriate bands
               4. Bands closely spaced (>6/mm)
     D. Marginal/Boundary
     E. Storied

IX. Ray Features seen in tangential view
     A. Long = > 1 mm high
     B. Seriation
          1. Exclusively 1-seriate
          2. 2- or 3-seriate
          3. 4 to 10-seriate
          4. > 10-seriate
     C. Aggregate rays
     D. Rays of two distinct widths
     E. Metric features (can use transverse sections)
          1. < 4/mm
          2. 4-12/mm
          3. >12/mm

X. Ray Features seen in radial view
     A. Homocellular = only procumbant cells
     B. Heterocellular = marginal cells
          1. 1 to 3 marginal cell rows
          2. => 4 marginal cell rows
     C. Bi- or tri-seriate parts narrow