ELMS : CREEPING WILLOW 243 



U. campestris, L. Twigs thick, bristly. Leaves thin, 

 venation hairy, upper surface scabrid, base hardly oblique, 

 margins sharply bi-serrate. Leaves much larger, 8 16 x 

 4 10 cm., especially the terminals, which are often cut 

 into 3 tips. Petiole very short and thick, 3 8 mm., hairy. 

 This is the species U. montana, Sm. 



U. effusa, Willd. Thin glabrous shining twigs. 

 Leaves thin, glabrous or roughish above, hairy beneath, 

 very oblique, sharply bi-serrate. Petiole short, 3 9 mm., 

 pubescent. This is not British, and is the same as U. 

 pedunculata, Foug. 



Numerous other forms have been distinguished, of 

 which only one need be mentioned, var. suberosa, Ehrb., 

 a variety of U. campestris with very corky twigs. 



The leaves of the Beech, usually entire, are oc- 

 casionally sufficiently sinuate-dentate to be looked for in 

 this group. They are oval, glabrous and glossy, and strict- 

 pinnate. See p. 284.] 



(0) Leaves spiral on both long and dwarf 

 shoots. 



* Leaves lanceolate, usually at least 4 times 

 as long as broad, and often much longer. 



t Leaves silky-pubescent, at least beneath. 



Leaves small, at most 16 cm. long, with 

 obscurely serratulate margins, and stipules 

 minute, or obsolete. Small creeper. 



Salix repens, L. Creeping Willow. Small creeping 

 arenicolous bush, with silky-velvety shoots and buds. 

 Leaves very variable, about 25 40 x 58 mm. (1 6 

 cm. x 1*5 15 mm.), elliptic to broad oval or ovate, oblong- 

 lanceolate to linear-lanceolate or even sub-linear. Silvery- 

 silky both sides, or glabrous and dark green above and 



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