MAINE AGRICUIvTURAI, EXPERIMENT STATION. 191O. 399 



a recent text-book on plant diseases, the Cylindrosporium dis- 

 ease has been indexed as "Baldwin Fruit Spot" and this leads 

 to more or less confusion. The writers have heard the opinion 

 expressed a number of times that the cause of Baldwin spot was 

 explained by Brooks' study of this fungus. They wish simply 

 to assist in making clear the fact that Brooks recognized and 

 described two distinct diseases and that the disease caused by 

 Cylindrosporium pomi is not the same as the well known Bald- 

 win spot, the characters and occurrence of which were so well 

 pointed out by Jones.* Unfortunately in Jones" account of 

 Baldwin spot he includes the results of Lamson's apparent con- 

 trol of the disease by spraying with bordeaux mixture. Brooks 

 shows, however, that there is every reason to believe that Lam- 

 son's results were really from the control of the Cylindrosporium 

 fruit spot which he confused with the true Baldwin spot. 



The Cylindrosporium fruit spot occurs on a number of varie- 

 ties of apples, and the writers are convinced by their observa- 

 tions that it does much more damage to some other varieties like 

 the Eellflower in Maine than it does to the Baldwin. 



According to Brooks, the Cylindrosporium disease appears 

 first about the middle of August. (The true Baldwin spot does 

 not appear till nearly harvest time or in storage). When it first 

 appears one notices spots of deeper red on the darker colored 

 portions and darker green on the lighter portions of the sur- 

 faces of affected apples. At this stage they are but slightly 

 sunken, if at all, and there is no suggestion of a bruise. From 

 Brooks' studies it appears that the fungous spots on red surfaces 

 become more sunken later in the season, the color gradually 

 changes from brown to black, and in cellar storage the red spots 

 become badly browned and sunken. The green spots may take 

 a similar course but in many cases there is no marked change in 

 their surface appearance. However, according to the expe- 

 rience of the writers, the spots caused by the fungus are not as 

 a rule so large and do not produce such deep pits in the surface 

 as are characteristic of later stages of the non-parasitic trouble. 

 Also on the lighter skinned apples there is not so much danger 

 of confusing the two troubles when one once has the characters 

 of each clearly in mind. 



On yellow-skinned apples like the Bellflower the spots are very 



* Jones, L. R. Vt. Exp. Sta. Rep. 12, p. 161. 1899. 



