458 Report op the Mycologist of the 



All of this is the work of a parasitic fungus, Glccosporium ncr- 

 visequum, which grows on the leaves and also on the young twigs. 

 By its growth on the young twigs they are killed, and then the 

 lateral buds develop into branches. The repetition of this pro- 

 cess results in the formation of a rosette. 



No practical remedy is known. 



Asparagus Rust. 



Long Island market gardeners apply the name " rust " to an 

 asparagus trouble in which the subterranean portion of the stem 

 shows irregular rust-colored patches. It is frequently quite de- 

 structive. The cause is unknown. 



Although the name " rust " is descriptive of this trouble, it 

 should not be used, for the reason that it is already preempted as 

 the proper name of an asparagus disease which is caused by the 

 fungus, Puccinia Asparagi DC. The name " rust " is properly 

 applied only to diseases caused by fungi belonging to the family 

 of rusts, Uredinew. 



Puccinia Asparagi is a true rust. It has rarely been reported 

 as destructive, but during the past year there has been a remark- 

 able outbreak of it in New Jersey, Long Island and southern New 

 England. Dr. Halsted, of New Brunswick, N. J., first directed 

 my attention to it last September. Upon examination the Long 

 Island asparagus fields were found to be badly affected. In 

 fields of several acres extent it was impossible to find a single 

 plant which was entirely free from the disease. 



Healthy asparagus plants will remain green until heavy frosts 

 occur, but plants affected with rust were dead and dry by Sep- 

 tember 1. The main stem and all of the branches were covered 

 with pustules (sori) which contained a brown powder — the spores 

 of the Puccinia. 



Dr. Halsted recommends burning over the affected fields in 

 autumn to destroy as many of the spores as possible, but it is our 

 opinion that this treatment has little or no practical value. 



Uromyces Trifolii (Hedw. f.) Lev. 

 This fungus is a true rust which is parasitic on various species 

 of clover. It presents the same general appearance as the other 



