DENDROLOGY WOOD ANATOMY LAB III - Conifer Wood Features & Identification I. The first part of this exercise will acquaint you with fundamental anatomical features of gymnosperm wood. You may wish to review these features on your own - feel free to do so. The numbers in (parentheses) following each feature below refers to the slide number in the green box labeled Gymnosperm Wood Demos. The numbers in [brackets] refer to the specimen numbers in the brown wooden XRT wood identification slide collection. You will find the on-line help in the Gymnosperm Wood component of the MUDES of benefit during this exercise. PLEASE RETURN ALL SLIDES TO THEIR APPROPRIATE SLOTS 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? The NUMBERS in the following outline refer to feature numbers in the softwood datasheet. NA implies that you will not encounter this feature in your study of our selection of North American woods. GENERAL FEATURES Spring to summer wood transition in growth rings 1. Growth rings indistinct (NA). 3. Latewood conspicuous eg. hard pines (DEMO 2) X [29] Other general features are best determined by inspection of solid wood samples and application of common sense. 2. Heartwood colored Juniperus Wood Block [22] 4. Distinct odor Juniperus Wood Block [22] 5. Distinct taste Taxodium Wood Block [24] 6. Greasy Taxodium Wood Block [24] 7. Dimpled grain (NA) LONGITUDINAL TRACHEIDS 8. Pits alternate (NA) 9. Pits > 1 seriate, opposite Pseudotsuga (DEMO 14) R [27] 10. Tori scalloped (NA) although we will show you an example of strap like extensions of tori in feature 51 Tsuga (DEMO 12) R. 11. Spirals in earlywood Pseudotsuga (DEMO 14) RT [27] 12. Callitroid thickenings (NA) LONGITUDINAL PARENCHYMA 13. Parenchyma present Chamaecyparis (DEMO 8) XRT Juniperus [22] 14. Parenchyma abundant Chamaecyparis (DEMO 8) XRT Juniperus [22] 15. Parenchyma end-walls nodular Taxodium (DEMO 10) T [24] RAY TRACHEIDS 16. Ray tracheids present (Larix, smooth not dentate) (DEMO 4) R [26] Dentate Ray Tracheids 17. Minute Picea (DEMO 7) R [25] 18. Average Pinus resinosa (DEMO 11) R 19. Reticulate Pinus echinata (DEMO 2) R [29] RAY PARENCHYMA Horizontal Walls 20. Thin Taxodium (DEMO 10) R [24] 21. Unpitted Taxodium (DEMO 10) R [24] 22. Well pitted Picea (DEMO 7) R [25] Other features 23. Indentures Taxodium (DEMO 10) R [24] 24. Wall corners thickened Sequoia (DEMO 9) T [23] 25. End walls nodular Pseudotsuga (DEMO 14) R [27] 26. > 30 cells high Sequoia,Taxodium (DEMO 9,10) T [23,24] 27. Crystals present Abies (DEMO 15) R CROSS-FIELD PITS 28. 1-3 Pinoid Soft pines (DEMO 1) R [28] 32. 1-6 Pinoid Hard pines (DEMO 16) R [29] 29. Piceoid Picea (DEMO 7) R [25] 30. Cupressoid Chaemaecyparis (DEMO 8) R [22] 31. Taxodioid Taxodium (DEMO 10) R [24] RESIN DUCTS 33. Normal vertical Pinus (DEMO 1) XRT [28] 34. Traumatic (NA) 35. Horizontal Pinus, Pseudotsuga (DEMO 1,14) XRT [28,27] 36. Thick epithelial cell walls Pseudotsuga (DEMO 14) XRT [27] RESIN DUCTS Number of epithelial cells / horizontal canal T 37. 5-6 Pseudotsuga (DEMO 14) T [27] 38. 7-12 Larix (DEMO 4) T [26] GEOGRAPHIC REGIONS 39-44,46-49 (NA) 45. North America Time, resources, and scope of objectives limit this class to consideration of woods endemic to the continent of North America. That's not to say that there are not plenty of woods worthy of your attention outside the scope of this class, we simply do not have the time or money to investigate them. PIT DETAIL 50. Notched pit borders Sequoia (DEMO 9) R [23] 51. Tori extensions Tsuga (DEMO 12) R II. Keying woods 1. Use the Gymnosperm Wood Component of the MUDES to identify specimens [22] through [29] in the wood identification collection. ULTIMATE OBJECTIVE: YOU WILL BE ABLE TO IDENTIFY 8 GENERA OF SOFT (GYMNOSPERM) WOOD BY EITHER SIGHT OR MICROSCOPIC IDENTIFICATION BY THE END OF THIS LABORATORY EXERCISE.