NOTES ON PLANT DISEASES OF CONNECTICUT. 7 2 3 



not injured. Some other conifers were also slightly injured, 

 but the deciduous trees escaped injury, though in the vicinity 

 of the kiln the maples and other trees are sometimes injured. 

 Previous smoke injury, complicated with drought injury, to 

 asparagus fields in the vicinity of this kiln, was mentioned in 

 our Report for 1908, page 858, and similar injury is claimed 

 to have been caused again this year. 



C. DISEASES OR HOSTS NOT PREVIOUSLY REPORTED. 



APPLE, Pyrus Malus. 



Fruit Spot, Cylindrosporium Pomi Brooks. Plate XXXIII a. 

 In our Reports for 1905, page 264, and 1907, page 340, we 

 described a fruit speck of apples that formed small, brownish, 

 spots in the skin of apples, being especially prominent after stor- 

 age. Cultures proved this trouble to be of fungous origin, but as 

 these cultures did not produce a fruiting stage of the fungus, we 

 were not sure of its identity. 



More recent study has shown that there are three fungi that 

 occur in fruit spots or specks of apples. One of these is the 

 black rot fungus, Sphaeropsis Malorum, which is more commonly 

 known not as a spot trouble, but as a general rot of the fruit, 

 especially on summer and fall varieties following insect injury. 

 This fungus is the one that we have most commonly isolated from 

 the fruit specks of market apples. Ordinarily it does not fruit 

 in the culture media on which we have grown it, and so it was 

 probably largely responsible for the fruit speck we describe in 

 the above reports, though Cylindrosporium Pomi was possibly 

 present in some cases. Besides the black rot, we have also occa- 

 sionally isolated a species of Alternaria which seems to be respon- 

 sible for speck injury, though we have as yet made no inoculation 

 tests to prove this. 



The third fruit spot, which we have seen frequently on the 

 fruit before it was gathered from the trees, as well as afterwards, 

 is that caused by Cylindrosporium Pomi, which was described a 

 few years ago as a new species by Brooks, who found it respon- 

 sible for a serious spotting of apples in New Hampshire. This 

 fruit spot on the market apples is usually very difficult to distin- 

 guish from that of the black rot. Perhaps the black rot fungus 



