462 NEW EXGLAXD TREES IN WINTER. 



CORK ELM 



Rock Elm, Hickory Elm, Northern Cork Elm. 



Ulmus racemosa Thomas. 



U. Thomasi Sarg. 





HABIT A large tree 50-75 ft. in height, with a trunk diameter of 

 2-3 ft., in southern Michigan, reaching 100 ft. in height with a trunk 

 diameter of 5 ft.; trunk slender, erect, generally continuous into the 

 crown, developing numerous slender rigid branches arising at a wide 

 angle, those below generally strongly drooping near the point of origin, 

 forming a narrow, oblong, round-topped head having somewhat the 

 aspect of a Hickory with short twiggy, generally corky-ridged branches 

 in the interior of the tree. A young tree showing corky-ridged 

 branchlets and an old tree showing a more characteristic habit, though 

 with rather long trunk for the open, are shown in the plate. 



BARK On young trunks more deeply furrowed than in the White 

 Elm, becoming with age flat-ridged, resembling the latter species. 



TWIGS More or less downy, resembling twigs of White Elm but 

 generally developing several irregular thick corky ridges not inter- 

 rupted at the nodes. 



LEAF-SCARS Alternate, 2-ranked, resembling these of White Elm 

 but with bundle-scars generally more than 3 (4-6). 



BUDS Terminal bud absent; lateral buds similar to those of White 

 Elm but longer (about 5 mm. long) narrower, sharp-pointed, scarcely 

 flattened, generally downy. BUD-SCALES with darker and hairy-edged 

 margins. 



PRI ! IT A flat, oval, downy, shallow-notched, winged fruit, with 

 hairy-fringed margins ripening in spring. 



COMPARISONS Tn Hickory-like habit the Cork Elm differs from 

 all our other Elms. The corky ridges on the twigs, moreover, occur 

 on no other native New England Elm. The Winged Elm [Ulmus alata 

 Michx.], a native of the south, is rarely cultivated in southern New 

 England but is not hardy north. It has two opposite thin corky ridges 

 which are abruptly interrupted at the nodes. A variety 9f the English 

 Elm has several corky ridges to the twig which are interrupted at 

 the nodes. The Cork Elm differs further from the White and especially 

 from the Slippery Elm in its narrower buds. 



DISTRIBUTION Dry, gravelly soils, rich soils, river banks. Quebec 

 through Ontario: south to Tennessee; west to Minnesota, Iowa, 

 Nebraska, and Missouri. Occasionally planted as an ornamental shade 

 tree. 



IN NEW ENGLAND Maine not reported; New Hampshire rare and 

 extremely local; Meriden and one or two other places; Vermont rare, 

 Bennington. Pownal. Knowlton. Highgate; comparatively abundant in 

 Champlain valley and westward; Massachusetts rare; Rhode Island 

 not reported native. 



IN CONNECTICUT Not reported native. 



\VOOD Heavy, hard, very strong and tough, close-grained and dif- 

 ficult to split, light clear brown, often tinged with red with thick, 

 lighter colored sapwood; largely used in the manufacture of many 

 agricultural implements, for the framework of chairs, hubs of wheels. 

 railroad ties, the sills of buildings and other purposes demanding 

 toughness, solidity and flexibility. 



