834 JOURNAL OF FORESTRY 



Foley informs us that the base of its composition is arsenic, and that 

 Atlas A is used by railroads in the U. S. A. as a track weedicide. One 

 interested in the chemical can write for particulars to Chipman Chem- 

 ical Engineering Company, Liberty street, New York, N. Y. 



Rock Elm 



The following notes were made by E. H. Frothingham during a re- 

 cent trip into northern Shawano and southern Langlade counties, Wis. : 



There has been some doubt as to whether the commercial rock elm 

 was identical with the true rock elm or cork elm {Ulmus racemosa) ; 

 it has been suggested that most of it was simply a dense wooded form 

 of the white elm {Ulmus Americana) . It would seem that the latter 

 suggestion is the more nearly correct; but this dense wooded form of 

 elm has characteristics which entitle it to recognition as distinct from 

 white elm, or at least from the commercial "soft elm." 



On this trip I talked with Mr. Louis Kemnitz, who has had large 

 experience in getting out rock elm timbers for the British Government, 

 and with Mr. Peter O'Connor, woods foreman for the Yawkey-Bissell 

 Lumber Co., who has had a long term of service in the- woods in this 

 region. I went into the woods on the Menominee Indian Reservation 

 with Mr. Kinney, of the Indian Forest Service, and was shown stand- 

 ing "rock elm" trees and the slash from trees which had been cut and 

 logged out by Kemnitz. In the Yawkey-Bissell holdings near White 

 Lake, Langlade county, Mr. O'Connor showed me logs and timber of 

 both "rock" elm and "soft" elm, and pointed out the difference between 

 them. None of the trees I saw had the characteristic corky twigs of 

 Ulmus racemosa. 



Mr. O'Connor identified my description of cork elm with what he 

 called the "shaggy twig elm," or "river elm," and said that this elm was 

 formerly much used for cant hooks and axe handles because of its 

 toughness. He said that this tree is entirely distinct from "rock elm." 

 It is smaller, both in height and diameter ("a river elm is pretty good 

 sized when over a foot in diameter"), and tapers more at the top. It 

 is even smaller than slippery elm. It is found on river flats. There 

 IS considerable of it around Wausau, and he has seen some on the Wolf 

 River, near New London, but there is none, or practically none, in the 

 region under discussion (Shawano and Langlade counties), which is 

 said to be the best "rock elm" territory in Wisconsin. When "rock" 

 elm is referred to in the following notes, therefore, it is undoubtedly not 

 cork elm ( Ulmus racemosa) . 



