26 MASS. EXPERIMENT STATION BULLETIN 327 



ect, and coordinating town projects. The total number of people employed 

 was 530, including scouts, supervisors, laboratory technicians, and ste- 

 nographers. Follow-up work in the laboratory is still in progress. Scouting 

 was done in every town in the State. Some 4,000 diseased specimens were 

 received at the laboratory, requiring the making and reading of 16,000 cultures. 

 Forty-one shade tree diseases were reported, 13 of which were diseases of the 

 American elm. 



The primary purpose of the survey was to determine whether the so-called 

 Dutch elm disease, caused by Ceratostomella ulmi (Swartz) Buisman, was 

 present in the State. This disease was first discovered in Holland in 1919 and 

 within a few years had spread over practically all of northwestern, central, 

 and southern Europe, virtually wiping out the elms in much of that area. In 

 1930, it was discovered in the United States. At that time a few affected trees 

 were found in Ohio and these were promptly destroyed. A much larger out- 

 break was discovered in the vicinity of New York Harbor in 1933. This area, 

 embracing portions of New Jersey, New York, and Connecticut, is about 6,000 

 square miles in extent, with the center at tne tip of Manhattan. Within this 

 area some 10,000 elm trees have been found affected with this disease and de- 

 stroyed because of it. A few isolated cases have appeared in Maryland, 

 Virginia and Indiana. 



The Dutch elm disease is not known to be present in Massachusetts. It has 

 been found, however, at two points within forty-five miles of the southern 

 border — at Old Lyme, Connecticut, and in Putnam County, New York. In 

 southwestern Connecticut, only a few miles farther away, approximately 100 

 trees have succumbed to the disease. 



Proximity of the disease in Connecticut and New York, known entrance at 

 Massachusetts ports of elm burl logs and other elm stock from Europe, and the 

 presence in the State for at least twenty-six years of the principal known carrier, 

 the smaller European elm bark beetle (Scolytus multisiriatus Marsh) furnish 

 ample reason for concern and justification for this survey. 



Prompt destruction of every elm tree found to be affected offers the only 

 hope of eradicating or checking the spread of this disease. Therefore, there 

 should be provision for prompt eradication measures in case the disease is dis- 

 covered in this State. 



While the survey did not result in discovery of the Dutch elm disease, a 

 large amount of significant and valuable data concerning other diseases of 

 shade trees was gathered and an intensive study of this material is in progress 

 in the laboratory. A number of elm diseases similar in effect to the Dutch 

 elm disease were found prevalent and causing heavy damage. Among these, 

 diseases caused by the fungi Cephalosporium sp., V erticillium dahliae Klebahn, 

 and Fusarium sp. were the most frequently reported. 



The entomological phases of this work have been conducted by the Depart- 

 ment of Entomology. 



Monograph of the Genus Pestalotia. (E. F. Guba, Waltham.) This is 

 not an official project and the work has been done entirely on the author's own 

 time. During a leave of absence from April 1 to October 1, 1935, progress ad- 

 vanced to a point warranting the assemblage of material for publication. The 

 preparation of the manuscript is now in progress. 



Testing Plants with Diphenylamine. (L.H.Jones.) This test for nitro- 

 gen deficiency has limitations which are more concerned with the plant under 

 consideration than with the test itself. Thus the base of the petiole may be 



