CHECK LIST OF FOREST TREES 49 



Yucca brevifolia Engelmann. 17 Joshua-tree. 



Range. — Southwestern Utah to California (to the western and northern 

 borders of the Mohave Desert.) 



Note ox nomenclature. — Formerly designated as Yucca arborescens (Torrey) 

 Trelease; at present also as Clistoyucca brevifolia (Engelmann) Rydberg. 



names in use 



Tree Yucca (Calif.). TToshua-tree (Utah, Ariz., N. Mex.). 



Yucca Cactus (Calif.). Joshua Yucca. 



The Joshua (Utah). 



Yucca elata Engelmann. 18 Soapweed. 



Range. — Southwestern Texas to southern Arizona; northern Mexico. 

 Note on nomenclature. — Formerly designated as Yucca constricta Buckley, 

 and as Yucca radiosa (Engelmann) Trelease. 



NAMES IN USE 



Spanish Bayonet and Spanish Sotol (Ariz.). 



Dagger. Southern Yucca. 



(Tex., N. Mex., and Ariz.). Soapweed. 



DIC OTYLED OlS T ES 

 Family CASUARINACE^ 



CASUARINA Forster 



Casuarina equisetifolia Forster. Beefwood. 



Range. — Native of tropical Asia and Australia. Naturalized in southern 

 Florida and Keys; also in the West Indies. 



NAMES IN USE 



Beefwood. Swamp Oak, Australian Oak. 



Ironwood. Australian Pine. 



Polynesian Ironwood. Horsetail-tree. 



She Oak. Horsetail Beefwood (hort.). 



Family JUGLANDACE^ 

 JUGLANS Linnaeus 



* Juglans cinerea Linnaeus. Butternut. 



Range. — -Southern New Brunswick to Delaware and on the Appalachian 

 Mountains to Georgia and Alabama (headwaters of Black Warrior River, Win- 

 ston County); westward through Ontario and upper peninsula of Michigan 

 to eastern South Dakota, eastern Iowa, southeastern Nebraska, central Kansas, 

 southern Missouri, and northern Arkansas. 



17 Trelease (Missouri Botanical Report 1902, 41) proposes for this tree the genus Clistoyucca, designating 

 the Joshua-tree as Clistoyucca arborescens (Torrey) Trelease. Britton and Shafer (North American Trees, 

 150, 1908) have followed Trelease in maintaining this name. 



IS Britton and Shafer (Opus cit., 152) have taken up for thus species Yucca elata Engelmann (1882), which 

 is based on Yucca angustifolia elata Engelmann (1873), while 0. S. Sargent (Manual Trees of North 

 America, 124, 1905, ed. I) maintained for this plant Yucca radiosa Trelease, which Is based on Yucca angus- 

 tifolia & radiosa Engelmann (1S71). The latter trinomial is the oldest combination applied to this yucca, 

 and were it not for a rule of nomenclature now observed the binomial Yucca radiosa (Engelmann) Trelease 

 (1892), derived from it, would be the oldest and therefore preferable name. Under the circumstances, how- 

 ever, Yucca elata Engelmann (1882) should be maintained. Sargent (Op. cit. ed. 2, 117, 1922) has lakeD 

 up the lattei Dame for this plant. 



