Forestry 280 Features of Woods 28-47
#28: Red Oak Quercus rubra Wide, oak-type ray Latewood Pores Earlywood Pores
#29: White Oak Quercus alba LW Pores Ray EW Pores Tyloses Banded Parenchyma
#30: Live Oak Quercus virginiana Semi-ring to diffuse porous; growth ring boundaries may be difficult to detect Broad, oak-type ray Aggregate ray Narrow rays also present
#31: American Chestnut Castanea dentata Structure similar to oaks, but no wide, oak-type rays Typically lower in density than oak Tyloses often found “Flame-shaped groups of LW pores”
#32: American Elm Ulmus americana Single row of EW pores LW pores in “wavy bands” (“ulmiform”)
#33: Slippery Elm (or Red Elm) Ulmus rubra EW Pores often in “several” rows (2-6) WOW! Look at those ULMIFORM LW PORES!
#34: Rock Elm Ulmus thomasii Earlywood Pores: Small and indistinct in intermittent, single row “A single interrupted row separated by smaller pores”
#35: Hackberry Celtis occidentalis Heartwood Color: Cream, light brown or light grayish brown w/yellowish cast Earlywood: More than one pore wide (akin to Slippery Elm) Latewood: Pores in wavy bands!! (Hackberry is in the Ulmaceae, or elm family)
#36: Red Mulberry Morus rubra LW Pores are in “nestlike groups”…sometimes forming concentric, interrupted bands – but not nearly so pronounced as in the elms. Loaded with tyloses! But, some samples have few to no tyloses…
#37: Osage Orange Maclura pomifera LOADED WITH TYLOSES: “USUALLY COMPLETELY OCCLUDED” LW pores in nested groups that form distinct concentric bands
#38: Kentucky Coffeetree Gymnocladus dioicus Nested LW pores more isolated, sometimes coalescing EW Pores in 1-few rows; open (no tyloses)
#39: Honeylocust Gleditsia triacanthos Looks a lot like Coffeetree – Don’t separate!! Note the heartwood color of #38 & 39
#40: Black Locust Robinia pseudoacacia Pores often completely occluded with tyloses Note LW pore pattern!
#41: White Ash Fraxinus americana Avg. SG: 0.60 Heartwood Color: Light brown or grayish brown Sapwood Color: Creamy white Pore Distribution: Ring-porous Earlywood: 2-4 pores wide; pores mod. large, surrounded by lighter tissue Latewood: Pores solitary and in radial multiples of 2-3 Tyloses: Fairly abundant Rays: Not distinct to eye, but clearly visible w/hand lens
#42: Black Ash Fraxinus nigra Avg. SG: 0.49 Heartwood Color: Grayish brown to medium or dark brown Sapwood Color: Creamy white Pore Distribution: Ring-porous Earlywood: 2-4 pores wide; pores large, surrounded by lighter tiss. Latewood: Pores solitary and in radial multiples of 2-3; not numerous Tyloses: Fairly abundant Rays: Not distinct to eye, but clearly visible w/hand lens
#43: Catalpa Note heartwood color Note lw pore patterns Tyloses “variably abundant”
#44: Butternut Juglans cinerea Avg. SG: 0.38 Heartwood Color: Medium or cinnamon brown, often w/uneven streaks of color, fluted growth rings Pore Distribution: Semi-ring-porous Pores: Earlywood pores fairly large, decreasing to small in latewood, solitary or in radial multiples of 2 to several Tyloses: Moderately abundant Parenchyma: Short tangential lines of banded parenchyma visible w/hand lens Rays: Fine but visible
#45: Black Walnut Juglans nigra Avg. SG: 0.55 Heartwood Color: Medium brown to deep chocolate brown Pore Distribution: Semi-ring-porous Pores: Earlywood pores fairly large, decreasing to quite small in outer latewood, pores solitary or in radial multiples of 2 to several Tyloses: Moderately abundant Parenchyma: Short tangential lines of banded parenchyma visible with lens Rays: Fine, visible but not conspicuous w/lens
#46: Hickory A True Hickory: Shagbark Hickory Carya ovata Note the “fishnet” (or “lace-like”) pattern in lw, formed by intersection of the fine rays and banded parenchyma True hickories are ring-porous
#46: Hickory - Pecan Hickory Carya illinoensis Pecan hickories are semi-ring porous…this looks like a poor example! (See next slide) What are these diagonal, whitish lines???
#46 - Hickory, Carya, spp. Pecan Hickory True Hickory
#47: Tanoak Lithocarpus densiflorus Wood is DIFFUSE porous The wide rays are “aggregate rays” that tend to be irregularly-spaced on the cross-section
Acknowledgement Photomacrographs by Zach Kriess Supplemental photomacrographs (those with white text showing scientific name) courtesy of the USDA Forest Service, Forest Products Laboratory