360 ' EXPERIMENT STATION EFCORD. [Vol.43 



St n 'I lift lis up to and including 1 oz. to 1 gal. of water did not injure the trees. 

 On the basis of their results, one peacli grower in New Jersey, wlio has 3,()00 

 6-.vear-()ld trees located on silt loam soil, has treated his orchard for 3 seasons 

 with sodium cyanid, applying 0.75 oz. to 1 gal. of water to each tree in Sep- 

 teniiter or October. During the season of 1919, 1 oz. of dry sodium cyanid per 

 tree was applied. As a result the orchard to-day is in excellent condition and 

 the peach borers have been greatly reduced. 



The author fotmd that 1 oz, treatments (liquid or granular form) of sodium 

 c.vanid will kill fi-om 75 to 90 per cent of the larvae in 5- to 10-year-old trees. 

 The granular or dry sodium cyanid is as efficient as the liquid (1 oz. to 1 gal. 

 of water) and nuich easier to apply. One-half oz., and in many cases 0.75 oz., 

 treatments for 5- to 10-year-old trees will not kill a sufficient number of larvfe 

 to constitute a practical control. Vigorously gi-owing peach trees 5 to 10 years 

 of age have not been injured by 1 oz. treatments when the applications were 

 made in May, June, September, or October. Also healthy trees 2 to 4 years 

 of age have not been injured by 0.5 oz. treatments. In the liquid treatments a 

 trough was dug about the tree 2 to 4 in. deep and the liquid was poured into 

 the trough so that it came in contact with the tree. In the dry treatment, fine, 

 granular sodium cyanid was used, sprinkled in the trough about the tree. The 

 greater part of tlie sodium c.yanid would be an inch or two away from the tree. 



Chrysanthemum midge, C. A. Wetgel and H. L. Sanford (U. S. Dcpt. Agr. 

 Bui. 8SS (1020), pp. 25, pis. 2, fl{l>^. 2). — The chrysanthemum midge {Diinihronn- 

 myUi hypogwa (F. Low), a European insect, was first recorded from the I'nitetl 

 States by Felt in 1915 (E. S. R., 34, p. 251), since which time it has been re- 

 ported as injurious from widely separated localities in this country and 

 Canada. Its injury is caused by the larvfe, which upon hatching out from eggs 

 deposited by the adult female on the surface of tender tips and new growth, 

 bore their way into the tissues, thereby giving rise to galls on the leaf, stem, 

 and flower head of the crysanthemum plant. The galls are cone-shape<l and 

 generally project obliquely from the surface, the length of the gall when fully 

 developed beipg about one-twelfth of an inch. When the leaf is affectetl, the 

 galls usually occur on the upper surface, a slight swelling often being observed 

 on the opposite or under side of the leaf. 



The 1915 report of its occurrence in this country was based upon an infes- 

 tation found by R. II. Pettit, of the Michigan Station, in large chrysanthe- 

 nuim houses at Adrian, Mich. Its occurrence at Ottawa, Canada, was reported 

 by Gibson in 1916 (E. S. R., 88, p. 358), and Essig recorded its occurrence in 

 California the same year (E. S. R., 36, p. 59), where it is thought to have 

 occurred for 15 years. 



The first severe infestation brought to the attention of the Bureau of Ento- 

 mology was on chrysanthenuims in greenhouses at Philadelphia in April, 1917, 

 the entire stock having been infested, causing a total loss to the gi'ower. Dur- 

 ing the same year, other florists reported a total loss of their stock of chrysan- 

 themums valued at several thousand dollars. A survey conducted by the 

 Imreiiu in Indiana, Illinois, and IMichigan during the months of November and- 

 December, 1918, in which greenhouses of 33 florists were visited, showed this 

 section to be one of the centers from which the pest was being distributed over 

 the United States, it having been found established in 8 of the 33 places 

 visited. 



While the species has been recorded from central and southern Europe as 

 seriously injuring the common white or oxeye daisy (Chrysanthemum leiican- 

 Ihcmum), as well as C. corynibosum, C. atratnm, C. jciponirum, and C. mijconis, 

 its dependatious in North America are confined to practically all of the com- 

 mercial chrysanthemums, both the single and pompon varieties. Attempts to 





