1506 The Trees of Great Britain and Ireland 



The Robinia has proved very useful in the afforestation of the steppes of Russia 

 and Hungary. The plantations in Hungary,^ mostly pure and growing on light dry 

 soil, covered an area of 70.000 hectares in 1899- These plantations are usually 

 treated as coppice with a rotation of twenty years. Illes^ states that in Hungary, 

 a plantation, fifty years old, produced 8800 cubic feet of timber per acre, the trees 

 averaging 90 ft. in height and 10 in. in diameter. In Roumania, the tree has been 

 used with great success in fixing the moving sands on the Danube, and 5000 to 6000 

 hectares have been planted. ("-J- •) 



ROBINIA NEOMEXICANA, Western Locust 



Jiohnia neomexicana. Gray, in Mem. Amer. Acad. v. 315 (1853); Sargent, SUva N. Amer. iil 43, 

 t. 114 (1892), and Trees N. Amer. 573 (igos)^ Wittmack and Brettschneider, in Gartenflora, 

 li. 649, t. 1385 (1892); Robinson, Flora and Syiva, 1904, p. 57, with coloured plate. 



A small tree, attaining 25 ft. in height and 2 ft. in girth, with thin scaly slightly 

 furrowed bark. Young branchlets densely covered with appressed pubescence, some 

 of which is retained in the second year. Leaflets nine to twenty-three, elliptical, 

 rounded at the base, acute or rounded at the apex, which ends in a long slender 

 mucro ; pubescence as in i?. Pseudacacia ; stipels, ^ in. long, often persistent ; 

 petiolules \ in. long, pubescent. The leaflets are somewhat smaller and bluer in 

 tint than those of R. Pseudacacia. 



Flowers' in short compact glandular long-peduncled racemes; calyx-lobes all 

 acuminate, appressed pubescent ; corolla pink or white tinged with pink ; standard 

 narrow with a yellow blotch on the inner surface. Pod about 3 in. long, glandular 

 pubescent. 



This species differs little in appearance from the common Robinia, but is 

 readily distinguished by the densely pubescent branchlets and the persistent stipels 

 at the base of the leaflets. In winter the branchlets retain some of the pubescence, 

 and are often covered with a glaucous bloom. The stipules become spinescent, as 

 in R. Pseudacacia, but retain traces of pubescence, and are not quite glabrous as in 

 that species. 



This species forms hybrids with R. Pseudacacia, which are described on p. 1500. 



R. neomexicana grows on the banks of mountain streams, and is distributed 



from the valley of the Purgatory river in southern Colorado through northern New 



Mexico to the Santa Catalina and Santa Rita Mountains in Arizona, whence it 



extends northward to southern Utah. It ascends to 7000 feet altitude. 



It was introduced* into cultivation in the Harvard Botanic Garden, U.S.A., in 



1 Cf. 'S>QQ^, Einfilhr. Ausland. Hoharten, 65 (1903). 



2 Quoted by Unwin, Future Forest Trees, 45 (1905). A plantation in France, fifty years old, yielded about 4300 cubic 

 ft. per acre. Cf. Bull. Soc. Forest. Franche-Comti, x. 18 (1 911). 



3 A form with white flowers is said to have been found wild in Arizona. Cf. Mitt. Deut. Dend. Ges. 1911, p. 423. 



* Cf. W. J. Bean, in Card. Chron. xxxv. 229 (1904). It appears to have been introduced on the Continent by Dieck, 

 who states in his catalogue, Neuheiten Offerte Nat. Arb. Zoschen, 1889-1890, p. 13, that he received it from Prof. Sargent. 

 It was soon afterwards obtained from the same source by Sp'ath. 



