/ Sphaerophysa Salsula, new to North America 



E. J. Alexander 



While driving along the highway in southern Colorado the 

 past August 27, near the town of Monte Vista, a bushy growth 

 bearing racemes of orange flowers drew the writer's attention. 

 I'pon examination, it was seen that the plant was a legume with 

 inflated papery pods. Now, as orange- flowered legumes are ex- 

 ceedingly rare in the North American flora, manuals were at 

 once searched for the plant's identity. There seemed to be 

 nothing even related to it recorded, so specimens were made and 

 seed collected for future examination. 



Recently, in looking over the specimens and making a more 

 complete check, the plant still could not be matched with any- 

 thing known in North America. In thinking over the various 

 leguminous genera with orange flowers, Colutea came to mind — 

 there might be an herbaceous species of that woody Asiatic 

 genus. Again a blank was drawn, so Bentham & Hooker's 

 Genera Plantarum was consulted, and it was plainly indicated 

 that the plant belonged in the sub-tribe Coluteae. It being highly 

 improbable that an Antipodean plant could have established 

 itself in temperate North America, the Asiatic genera were 

 examined, and the plant was soon identified beyond doubt as 

 Sphaerophysa Salsula (Pall.) DC, native of northern and cen- 

 tral Asia, the genus merged by some botanists with Swainsona, 

 a strictly Australian genus. In either case, the discovery of this 

 plant adds a new genus and species to the North American 

 flora, but its source in that locality is a matter of conjecture. 

 In that section, the highway and railroad run parallel for some 

 miles, separated by a 100-foot strip of ground filled with grass 

 and weeds, a logical situation for an introduced plant. Sphaero- 

 physa grows in that strip of ground, in at least a half dozen 

 colonies scattered over as many miles, and always within ten 

 •feet of the highway. 



The plant is about three feet tall, gregarious, in general ap- 

 pearance much like an erect Astragalus, the stems arising from 

 underground, woody rootstocks. The leaves are alternate, 5-7 

 cm. long, with 9-19 elliptic to obovate leaflets 5-10 mm. long, 

 the pairs subopposite. The entire plant is closely strigose- 

 puberulent except for the upper surface of the leaflets and the 



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