DENDROLOGY WOOD ANATOMY LAB IV 

I.  The first part of this exercise will acquaint you with fundamental anatomical features of
gymnosperm wood. The numbers in (# DEMO) following each feature below refers to the slide number 
in the box labeled Angiosperm Wood Demos.  The numbers in [brackets] refer to the specimen numbers
in the wood identification collection.  You will find the on-line help in the Angiosperm Wood component 
of the MUDES of use during this exercise.

PLEASE RETURN ALL SLIDES TO THEIR APPROPRIATE SLOTS AND BOXES WHEN YOU ARE DONE VIEWING THEM. 

Specific objectives for you to strive to master include:  a)  What section (transverse X, radial
longitudinal R, or tangential longitudinal T) is best to use in assessing a particular character
state?  Hints are provided via abbreviations in the outline below.  b)  What are the features
associated with each character that will permit you to classify the state of that character? 

GROWTH RINGS

Variation in vessel size within a growth ring

 	Ring porous Quercus (DEMO 2) X [14]
 	Semi-ring porous Prunus (DEMO 1) X [9]
 	Diffuse porous Nyssa (DEMO 3) X Acer [4]

VESSELS

Pattern of aggregation

 	Exclusively solitary  Eucalyptus (DEMO 4) X Quercus [14]
 	Radial groups of 2-4 Carya [19]
 	Radial groups of 4 Amyris (DEMO 5) X Ilex [6]
 	Radial or oblique Castanea (DEMO 6) X [16]
 	Tangential arrangement Ulmus (DEMO 25) X [11]
 	Pore clusters  Gymnocladus (DEMO 26) X Platanus [7]

Perforation Plates

 	Perforation plate simple  Castanea (DEMO 6) RT [16]
 	Multiple perforation plate Liriodendron (DEMO 7) RT [12]
 	Sclariform plates with > 20 bars Liquidambar (DEMO 23) X [8]





Pit and wall details

 	Spiral thickenings  Magnolia (DEMO 8) RT [10]
 	Pits minute Betula (DEMO 9) R [13]
 	Pits opposite or scalariform Liriodendron (DEMO 7) RT [12] or Magnolia (DEMO 8) RT [10]
 	Pits alternate Betula (DEMO 9) RT [13]

Lumen features

 	Tyloses abundant Quercus alba (DEMO 10) XRT [15]

Metric features

    Count the number seen in a 10X objective field:

 	Fewer than 5/sq. mm Carya illinoensis [19]
 	Fewer than 20/sq. mm
 	20-40/sq. mm Soft Maple [4]
 	More than 40/sq. mm Fagus [17]

    Tangential diameter.  Determine this feature using wood samples:

 	< 50 microns - Not visible to naked eye. Ilex [6]
 	50-99 microns - Larger pores barely visible to naked eye. Soft Maple [4]
 	100-200 microns  - Visible to naked eye Betula [13]
 	> 200 microns - Distictly visible to naked eye. Carya illionensis [19]

OTHER ELONGATED AXIAL CELLS

 	Fibers Diospyros (DEMO 12) XRT Fraxinus [1]
 	Fiber tracheids Diospyros (DEMO 2) R Carya [18]
 	Vascular Tracheids Quercus (DEMO 10) XR [14]
 	Vasicentric Tracheids Quercus (DEMO 10) XR [14]
 	Spiral thickenings Ilex (DEMO 13) RT [6]

RAYS

 	Commonly > 1 mm high  Ilex (DEMO 13) T [6]
 	Aggregate rays Robinia (DEMO 16) T
 	Two distinct widths Quercus (DEMO 10) T [14]
   



 
    Degree of seriation.
 
 	Exclusively 1-seriate Populus (DEMO 14) T Tilia [3]
 	Commonly 2-3-seriate Fraxinus nigra [2].
 	Commonly 4-10-seriate Ilex (DEMO 13) T [6]
 	Commonly > 10-seriate Platanus (DEMO 15) T [7]
   
    Type of marginal cells.

 	Homocellular Populus (DEMO 14) RT Betula [13]
 	1-3 marginal rows Ochroma (DEMO 17) RT Liriodendron [12].
 	4-9 marginal rows Nyssa (DEMO 3) RT Ilex [6]
 	10 or more marginal rows Gleospermum (DEMO 18) RT

    Metric features.

 	Commonly < 4/mm Platanus (DEMO 15) XT [7]
 	4-12/mm Castanea (DEMO 6)  XT [16].
 	Commonly > 12/mm (NA)
 	Ray parenchyma - vessel pits > 10 micrometers Weinmannia (DEMO 19) R Castanea [16]

AXIAL PARENCHYMA  

    Use polarized optics to facilitate identification.

 	Apotracheal Lithocarpus (DEMO 20) X Juglans cinerea [21]
 	Diffuse Malpighia (DEMO 21) X Juglans cinerea [21]
 	Paratracheal Castanea (DEMO 6) X [16]
 	Vasicentric Weinmannia (DEMO 19) X Ulmus [11]
 	Aliform or confluent  Maclura (DEMO 22) X Fraxinus [1]
 	Rare or absent Liquidambar (DEMO 23) X [8]
 	Banded Maclura (DEMO 22) X Fraxinus [1]
 	Bands 1-seriate Platanus (DEMO 15) X [7]
 	Bands > 4 seriate Robinia (DEMO 16) X
 	Bands > 6/mm Carya illinoiensis (DEMO 24) X [19]
 	Marginal/zonate Fraxinus (DEMO 25) X [1]

II.  Keying woods.  The second part of this exercise will give you practice in applying what
you mastered in the first section.  Using what you have learned relative to character state
assessment identify the "unknown" angiosperm specimens 1-21, using the wood and XRT
slide samples that are provided and the Angiosperm Wood component of the MUDES.

   ALL WOOD SAMPLES AND WOOD XRT SLIDES MUST BE REPLACED IN THE
                   EXACT POSITION FROM WHICH YOU OBTAINED THEM!. 


ULTIMATE OBJECTIVE:  YOU WILL BE ABLE TO IDENTIFY  21 KINDS OF HARD
(ANGIOSPERM) WOOD EITHER BY SIGHT OR MICROSCOPIC IDENTIFICATION.