ROCK ELM; CORK ELM (Ulmus Thomasi, Sarg.). 80 to 100 

 feet. Tall-trunked, rugged, stiff-looking tree with narrow, 

 round head. Bark shaggy on large limbs and trunk, which is 

 gray tinged with red, r*nd irregularly cleft into broad, flat, 

 s^aly ridges. Twigs stiff, pubescent, with warty leaf-scars 

 and lenticels, at length ridged with 3 or 4 uneven, corky 

 idges. Wood like that of preceding species but superior in 

 strength and flexibility. Used for same purposes. Leaves 2 

 to 2-| inches long, oblong-oval, pointed at both ends, scarcely 

 oblique, at base, coarsely saw-toothed, with finer serrations, 

 thick, firm, smooth above, paler, pubescent below, especially 

 on veins. Flowers in drooping racemes, each flower stalked, 

 pubescent, with green calyx tinged with red toward its 

 5 to 7 cleft rim. Fruit clustered, each \ inch long, ovate, 

 flattened, with broad wing encircling the seed. Ripe and 

 wind-sown early in summer. Dist.: Bluffs and dry uplands 

 or low, heavy clay soils, Quebec and Ontario and adjoining 

 states; west to Nebraska and Missouri. Most abundant and 

 finest in Ontario and Michigan. 



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