A Study of Meadow-Crop Diseases in New York 73 



but they subsequently enlarge in the direction of the long axis of the 

 stem and become sunken so that at times the pith may be exposed. They 

 may reach from 4 to 5 centimeters by ^ centimeter in size. At such stages 

 the upper part of the stem wilts, turns brown, and dies, giving the field a 

 scorched appearance. Infections on tender petioles or flower pedicles 

 causes these organs to wither and fall over. This also is very charac- 

 teristic of the disease, especially in the spring when environmental con- 

 ditions are right. Sometimes the pulvini of the leaves are infected as 

 pointed out by Miss Sampson (Stapledon and others, 1922:83-87), but 

 infections of the lamina are rare. In wet weather the minute white 

 fruiting bodies of the fungus, the acervuli, may be seen with a hand lens 

 in the center of the lesions. 



Etiology 



Name, history, and classification of the pathogene. Four pathogenes, 

 said to cause clover anthracnoses, have been described. Peck (1880:26) 

 described Gloeosporium trifolii in New York as occuring on leaves of red 

 clover. Kirchner (1902:12) twenty-two years later described a species 

 Gloeosporium caulivorum, which he distinguished from G. trifolii because 

 it occurs exclusively on stems and petioles and because the spores are 

 curved instead of straight. He did not detect any differences in size. 

 Very frequently these two have been considered identical in Europe 

 (Baudys, 1924, and Voglino, 1909). In America, however, G. caulivorum 

 Kirch, usually has been cited as the cause of clover anthracnose. 



Bain and Essary (1906 a: 193) found still another organism, which they 

 named Colletotrichum trifolii because the spores are straight and setae are 

 present in the acervuli. This organism, which seems actually different, 

 has been treated thoroughly in the recent publication of Monteith (1928). 

 O'Gara (1915) distinguishes as new Colletotrichum destructivum on T. 

 pratense and T. hybridum because there are no definite spots, and the spores 

 and setae are much larger than those of C. trifolii Bain and Essary. 



According to a recent paper by Miss Sampson (1928:104), Karakulin 

 (1923) changed Gloeosporium caulivorum Kirch, to Kabatiella caulivora 

 (Kirch.) Karak. Miss Sampson states, " My own observations show 

 that it is not a typical Gloeosporium, since it is characterized by a scanty 

 growth of mycelium in the host and on culture media, the absence of a 

 definite stroma beneath the acervulus, and the short club-shaped coni- 

 diophore bearing a terminal crown of conidia. These characters agree 

 with those of the genus, Kabatiella Bub., as emended by Karakulin." 



The causal agent of clover anthracnose in New York agrees with this 

 description, and it is considered here as being K. caulivora. It is sufficient 

 to point out with Baudys (1924) that the position of the fructification is 

 small ground for separating species, and hence that G. trifolii Peck, is 



