ACACIA 



width apart : sometimes gently avoiding the pores : red : very 

 many, crowded, 9-14 per mm. 



Rings. Clear (prominent with lens in the black wood only) : 

 boundary, a poreless zone and a line of contrast between the 

 coarse ground-tissue of the inner and the dense outer wood of 

 the ring. 



Soft-tissue. Encircling the pores and in well developed 

 rings, joining them up to oblique, wavy lines. 



Pith. " Small, lobed (rund-eckig) of brownish or yellowish- 

 red cells " (86). 



Radial Section. Pores, fine scratches visible chiefly in the 

 dark wood. Rays just visible as fine red flakes. 



Tangential Section. As the Radial, but the rays need the 

 microscope, and the rings are fairly evident especially in the 

 dark wood. 



Type specimen authenticated by the Forest Officer to the 

 Government of Natal. Rhus does not much resemble the 

 other genera of the same order. 



No. 51. ACACIA. Robinia Pseudacacia. Linn. 



Plate IV. Fig. 36. 



Natural Order. Leguminosea. 



Synonyms. R. fragilis Salisb. Pseudacacia odorata. Moench. 



Alternative Names. False Acacia. Locust. Yellow Locust : 

 Black Locust : Red Locust in U.S. America (49). Virginische 

 Schotendorn (68). 



Sources of Supply. Europe. British Isles. North America. 



Physical Characters, etc. Weight 36-52 lbs. per cu. ft. Hard- 

 ness Grade 5, compare Ash, Elm. Smell and taste none when 

 dry : "like green bean-pods when fresh felled" (87). Burns well 

 with much crackling, embers glow in still air but soon die out. 

 Solution with water and alcohol, olive- yellow. 



Grain. Coarse, open and sinuous. Surface lustrous and 

 satiny : the ground-tissue bright, the pores and rays dull. 



Bark. Thin, J~| inch, deeply fissured : shining when young : 

 stringy, laminated bast within. 



Uses, etc. Posts, tree-nails, ribs of vessels, turnery. In France, 

 " chairs, furniture, joists, spokes, rungs of ladders — almost 

 incorruptible — stronger and more durable than Oak" (78). 

 "Elastic and of a vertical resistance one-third greater than 

 Oak — the best wood for spokes — more valuable than Oak, 

 Elm, or Ash "(69). "Very durable in contact with the ground 

 — shipbuilding, posts, works of construction — preferred to all 

 others for tree-nails " (106). Note. — As this tree grows as fast 

 as the Beech, and as its timber is so valuable, it is worthy of 



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