ANNUAL REPORT, 1942 17 



eradication of diseased trees is under the direction of the State Department of 

 Agriculture which has cooperated also in the entire program. The infection of 

 trees in the southwestern part of Berkshire County and Westfield, Massachusetts, 

 apparently does not indicate direct spread of the disease between these two regions 

 within the State, but rather the introduction of the disease into the State at two 

 separate points, presumably from a commcn source in the extension of the in- 

 festation radiating from the area around New York City. 



In order to protect disease-free 'elms, concerted effort has been directed toward 

 the elimination of freshly cut elm wood. At present this procedure is the most 

 practical control that can be employed effectively in checking the spread of the 

 disease. Since the disease fungus is virtually a prisoner within an affected tree, 

 it cannot spread significantly except as it is carried from a diseased to an unin- 

 fected tree by a vector. The best evidence indicates that the smaller European 

 elm bark beetle, Scolytus multistriatus Marsh., is the principal carrier Insect. 

 This insect invades the bark of weakened trees or freshly cut elm wood, where 

 eggs are laid in galleries engraved between the bark and wood. Upon emergence, 

 the beetles feed on healthy elm twigs and in this manner may facilitate fungus 

 infect'on of healthy trees if the feeding beetles come from galleries in diseased 

 wood. The beetle is now known to occur in Springfield, West Springfield, and 

 Westfield in Hampden County, and widel> in Berkshire County, in addition to 

 the originally known eastern Massachusetts section of infestation which has 

 been enlarged to include most of the area east of Worcester County. 



The prompt destruction by burning of all freshly cut elm wood which is well 

 suited for infestation by bark beetles is urged upon all agencies and Individuals 

 whose work brings them into contact with it, unless there is complete assurance 

 that the bark will be removed immediately after the wood is cut or other provision 

 is made for the consumption of any fungus- free wood as fuel in cooperative agree- 

 ments. Tree wardens, foresters, arborists, fire wardens, highway departments, 

 state departments, and public utilities have cooperated generously in aiding in 

 this practical method of protecting disease-free elms. As in the case of all diseases 

 of plants, however, unbroken continuity of the program is most essential. 



Other Tree Problems. Sixty-three diseases of thirty-four species of trees, in- 

 cluding nine diseases of elm, were identified from approximately 300 specimens 

 and inquiries received during the year. The Cephalosporium wilt of elm was re- 

 ported from 4 municipalities in which no previous cases of the disease had been 

 reported, making a total of 177 cities and towns in which the disease has been 

 found in Massachusetts. The fungus, Verticillium sp., was isolated from several 

 species of woody plants, but no specimens were received from municipalities not 

 included in the total of 96 reported for 1941. 



Following an extended period of wet weather early in the growing season, leaf- 

 inhabiting fungi caused considerable damage to foliage. Trees throughout 

 Massachusetts were affected. 



A nonparasitic disease of white pine, commonly known as needle-blight, In 

 which needles of the current season discolor to varying degrees beginning near 

 the tips, was rather prevalent both on ornamental trees and in plantations. 



At the request of the Massachusetts Tree Wardens' and Foresters' Association, 

 a report on wartime municipal tree programs was prepared, and subsequently a 

 survey of tree diseases and other defects was made, with a view to outlining a 

 program for tree protection and the prevention of damage by defective trees .to 

 persons and property. Current miscellaneous activities included the preparation 

 of parts of the program of the annual Five-day Short Course for Tree Wardens, 

 the compilation of a progress report, revision and publication of a manuscript 

 on a Peridermium of northern hard pines, the discussion of the control of wood- 



