54 ERICACEAE. Arbutus. 



1 66. Arbutus Menziesii, Pursh. 

 Madrona. 



Islands of British Columbia, southward through Washington and Ore- 

 gon, near the coast, and through the Coast Ranges of California to the 

 Santa Lucia Mountains. 



A small tree, sometimes 15 to 25 metres in height, with a trunk 0.90 

 to 1.20 metres in diameter, or rarely much larger ; south of San Francisco 

 Bay smaller, often reduced to a low shrub ; hillsides in rich soil. 



Wood heavy, hard, strong, close-grained, checking in drying ; medul- 

 lary rays numerous, conspicuous ; color light brown shaded with red, the 

 sap-wood lighter ; largely used in the manufacture of gunpowder, the bark 

 in tanning. 



167. Arbutus Xalapensis, HBK. 



Southern Arizona, — Santa Rita Mountains, between 4,500 and 7,000 

 feet elevation ; in northern Mexico. 



A small tree, 9 to 12 metres in height, with a trunk 0.45 to 0.60 metre 

 in diameter ; dry, gravelly slopes ; the large specimens generally hollow 

 and defective. 



Wood heavy, soft, not strong, brittle, close-grained, checking badly in 

 drying, susceptible of a good polish ; medullary rays numerous, obscure ; 

 color light brown, tinged with red, the sap-wood lighter. 



168. Arbutus Texana, Buckley. 



Western Texas, Hays and Travis Counties, west to the Guadalupe and 

 Eagle Mountains, and southward, probably into northern Mexico. 



A small tree, 5 to 6 metres in height, with a trunk 0.15 to 0.25 metre 

 in diameter ; dry limestone hills and ridges ; rare and local. 



Wood heavy, hard, close-grained, compact ; medullary rays numerous, 

 obscure ; color brown, the sap-wood lighter, tinged with red ; used in 

 turnery, the manufacture of mathematical instruments, etc. 



169. Oxydendrum arboreum, DC. 

 Sorrel Tree. Sour-wood. 



Western Pennsylvania, south along the Alleghany Mountains to west- 

 ern Florida and the eastern shores of Mobile Bay, west to middle Ten- 

 nessee and western Louisiana. 



A small tree, 12 to 18 metres in height, with a trunk 0.25 to 0.35 

 metre in diameter ; usually in rather dry, gravelly soil. 



Wood heavy, hard, very close-grained, compact, susceptible of a beau- 

 tiful polish ; medullary rays numerous, thin ; color brown tinged with red, 

 the sap-wood somewhat lighter; used for the handles of tools, bearings of 

 machinery, etc. 



