2 BULLETIN 1223, U. S. DEPARTMENT OF AGRICULTURE. 



the native elm also produces wood which is particularly valuable in 

 the making of vehicles, baskets, crating, etc. 



The European elm scale infests all species of elm, having become 

 such a very disagreeable and harmful pest that in many eastern 

 localities these trees are no longer recommended for planting. In 

 the West the scale insect is not so widely distributed, nor are many 

 of its eastern associates present, so that in spite of the elm scale the 

 tree is still recognized as one of the best for shade. 



Fortunately, the scale in America infests only elms and is not a 

 pest on fruit or other shade trees, as are many of the aggressive 

 scale insects. 



HISTORY. 



This insect was first noted in the United States in 1884, when 

 Charles Fremd found it infesting elm trees in his nursery at Rye, 

 Westchester County, N. Y. It had undoubtedly been imported 

 from Europe, where it has been known for nearly 200 years. It 

 was next reported by Professor Comstock from New York City, 

 where he had found it rather abundant in the winter of 1886-7. A 

 few months later John G. Jack sent specimens to the United States 

 Bureau of Entomology from slippery elm growing at Cambridge, 

 Mass. In 1888 it was found at Washington, D. C, infesting elms 

 on the grounds of the Department of Agriculture and also in two 

 localities on the streets of the city. 



Up to this time it had not been positively identified, but the nest 

 year Dr. L. O. Howard made a thorough study of the insect and 

 identified it as the European elm scale {10). , 3 



A few' years later this scale insect was found to have invaded the 

 western part of the United States. In 1894, Alexander Craw (#), 

 of the California State Board of Horticulture, reported that during 

 the previous season E. M. Ehrhorn had noted the European elm 

 scale upon elms at Stanford University, California. The next year 

 Mr. Hillman, entomologist of Nevada, reported it from Reno, Nev., 

 and in 1906 A. L. Melander (16), entomologist of Washington, 

 stated that it had been in Spokane, Wash., for several years. 



From time to time it has been reported from one State or another 

 until it is now known to occur in 27 States besides the District cf 

 Columbia. 



SYNONYMY. 



As early as 1738 this scale was known in Europe, at which time 

 Reaumur (18) figured the female in all its stages and gave its 

 natural history, but failed to give it a name except that of "pro- 

 gallinsecte " of the elm. 



The first name given to it was Coccus ulmi by Linnaeus (1J/., p. 265) 

 in 1761. In 1875, Signoret (19, p. 21) removed this insect from the 

 genus Coccus and erected a new genus, Gossyparia, with ulmi as 

 the type. The specific name ulmi was retained until recently, when 

 it was discovered that it rightfully belonged to another insect named 

 Coccus ulmi Linnaeus (IS, p. 455) in 1758, since removed to the 

 genus Lepidosaphes. Consequently the next specific name used for 

 the European elm scale, spurius, applied to it in 1^78 by Modeer 



8 Numbers in parentheses (italic) refer to Literature cited, p. 18. 



