NOTES ON PLANT DISEASES OF CONNECTICUT. 7 J 7 



fourteen towns; Hartford County, seven towns; Middlesex 

 County, two towns; Tolland County, three towns; Windham 

 County, one town; New London County, one town. This 

 makes a total of seventy-two towns, of which only seven are 

 east of the Connecticut River. We have no doubt that a more 

 thorough survey of that region would reveal its presence, in 

 an inconspicuous way, in quite a few more towns. 



This increased distribution in the last three years may indicate 

 that the disease has spread to those new localities, or it may 

 mean that a more thorough search has revealed its presence, 

 and that it has also become more prominent because of the 

 four years of drought that have occurred, beginning with 1907. 

 There are those who believe, however, that unfavorable weather 

 conditions have nothing to do with the prominence of this dis- 

 ease, which they suspect to be a recent importation into this 

 country from Japan. If this theory is true, then we are just 

 beginning to feel the effects of its devastation in this state. 

 Personally, we have not yet found convincing proofs to cause 

 us to change our views expressed in the above-mentioned Report. 

 These views, briefly given, are (i) that the fungus is a native, 

 weak parasite, usually very inconspicuous in its damage, and 

 therefore rarely noticed; and (2) that the unusual winter of 

 1904, by severely injuring chestnut trees, gave it a chance to 

 spring into unusual and sudden prominence, which it has since 

 maintained and even increased by reason of four successive years 

 of drought, that have injured not only chestnuts, but many other 

 trees. 



We do not, and never have, questioned its seriousness. Trees 

 that have been marked in two localities by the botanical and 

 the forestry departments have uniformly showed injury greatly 

 in excess of that indicated when first examined. If our theory 

 is correct, we do believe, however, with the return of several 

 normally wet years the trouble will gradually grow less rather 

 than more conspicuous as it should if weakened vitality of the 

 trees has nothing to do with its development. 



ELM, Ulmus americana. 



LEAF SPOT, Gnomonia Ulmea (Schw.) Thuem. Plate XXXIV. 

 During the summer of 1909 several complaints came to the 

 station of elm trees shedding their leaves where the elm leaf 



