164 JOURNAL OF THE ARNOLD ARBORETUM [vol. ii 



NOTES ON NORTH AMERICAN TREES. VHP 



C. S. Sargent 



Robinia Pseudoacacia L. in Illinois and Indiana. 



Illinois is one of the states in which the Black Locust has usually been 

 considered to have been naturalized and not indigenous. The elder 

 Michaux, however, included it in the list of plants which he collected 

 "au long du Mississippi" on October 9, 1795 (see Journal of Andr6 Mic^h- 

 aux, 1787-96, p. 124). On the ])rcvious day Michaux had arrived "au 

 P^ort Cheroquis autrement nomine par les Americains Fort Massac." 

 This was on the Ohio River in Massac County, Illinois, in what is now 

 a State Park and the nearest point to Fort Massac on the Mississippi 

 River is in wliat is now Alexander County, Illinois, a considerable dis- 

 tance to have been covered at that time in one day. In commenting on 

 Michaux \s discovery of the Rol)inia in southern Illinois Dr. Robert 

 Ridgwny, the distinguished ornithologist, who for many years has studied 

 the trees of southern Illinois, writes, — "Now at the time of Michaux's 

 visit it is impossible that any tree could have been established there 

 through naturalization. There were no white inhabitants in the country 

 except a f<nv French (mostly hunters and traders) at Kaskaskia and at a 

 very few other ])laccs, and these came from the north where Robinia does 

 not grow. The Black Locust is common in the hilly district (Ozark 

 Uplift) of the southern counties and I have no doubt it is indigenous there. 

 In other parts of southern Illinois, however, it is unquestionably an intro- 

 luced and naturalized species, having been planted by the early settlers 

 from Kentucky, Ohio, etc., about their homes. Even now it is rarely 

 if ever seen in the woods except in the Ozark region where it grows inter- 

 mingled with other forest trees." 



It is probable, loo, that the Black Locust was indigenous in southwest- 

 ern Indiana as it was included in tlie list of "vegetables growing indigen- 

 ously near the Wabash, between Vinccnnes and Fort Harrison," seen by 

 David Thomas in 1816 and printed on pp. 22^-24 of his Travels through 

 the Western Country in the summer of 1816. 



Robinia neomexicana A. Gray. Gray based his description of this 

 plant on a specimen collected in May, 1851, on '*dry hills on the Mem- 

 l)res" by Dr. George Thurber. The leaflets arc oblong-elliptic and acute, 

 and are finely pubescent below. The petiole and rachis of the leaves 

 are j>ubescent and partially covered with slender minutely glandular 

 hairs which are more abundant on the calj'x of the flower. The fruit 

 hu^ not been collected apparently at the type station, Init a cluster of 



( 



pods collected by II. II. Rusby in 1881 at Mangos Springs in the same 

 locality shows that it is slightly stellate-pubescent and entirely destitute 

 of the stout glandular-hispid hairs which have been ascribed to it and 



^ For part \'1I ncc p. 112. 



