THE ROCK ELM OR CORK ELM 



THE very striking peculiarity which distinguishes the Cork Elm from the other 

 native species is clearly shown in the tree pictured on the plate, as well as in the 

 branch from which the leaf-bearing twig arises. The peculiar corky ridges upon 

 the secondary branches give the tree a very different appearance from that of any other, 

 and enables one always to distinguish this species with ease and certainty. The tree is 

 especially likely to be found along high river banks or in rather dry, rich soils, and is irreg- 

 ularly distributed throughout a rather limited range, extending from Quebec and Onta- 

 rio on the north, south through parts of New England and New York to New Jersey, and 

 west to Wisconsin, Nebraska, and Missouri. According to Professor Sargent it is most 

 abundant in Michigan and Ontario. 



In its best estate the Cork Elm will bear comparison in size and dignity with the 

 noble American Elm, although it lacks some of the grace of the latter species. The tree 

 occasionally reaches a height of a hundred feet and a trunk diameter of three feet, although 

 generally it is much smaller. The grayish bark of the trunk is marked by numerous ver- 

 tical fissures, between which are many large, loosened scales. The winter buds are hairy, 

 resembling in this respect those of the Slippery Elm. 



In regions where the tree is abundant the wood is used for a great variety of manu- 

 facturing purposes, it being heavy, hard, close-grained and weighing forty-five pounds per 

 cubic foot. On account of the valuable qualities of the wood the species is sometimes 

 called the Hickory Elm, and on account of the fact that it often grows upon rocky ledges 

 it is sometimes called the Cliff Elm. 



Like the other members of the genus the Cork Elm blossoms very early in spring, 

 before the leaves push out, but unlike the other species the blossoms are borne in distinct 

 racemes, a fact which led to the technical name, Ulmus racemosa. These racemes shortly 

 develop into the hairy fruits represented in the upper left-hand picture of the plate, these 

 fruits being somewhat larger than those of the American Elm and smaller than those of 

 the Slippery Elm. 



This species has been rather extensively planted for shade and ornament in cities 

 along the Pacific coast. It proved to be of rapid growth and desirable except for the fact 

 that it sent its roots long distances in search of water and from these roots there came up 

 numerous suckers that were difficult to destroy, especially when the tree itself had been 

 cut down. A writer in The Garden Magazine says that on account of gardens ruined by 

 these suckers the Cork Elm is no longer planted. 



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