240 



PLANT DISEASES 



After the crop is gathered, the summer plants might be 

 sprayed with Bordeaux mixture to keep the fungus in check ; 



Fig. 61. Puccinia asparagi, i, aecidium stage on a 

 young shoot of asparagus ; 2, teleutospore condition on a 

 summer plant; 3, aecidiospores, X3oo; 4, uredospores, X3oo; 

 5, teleutospores, X3oo. 



but the important point is to remove diseased plants, and 

 so by degrees prevent the possibility of infection in the 

 spring. 



MINT RUST 



(Puccinia menthae^ Pers.) 



Whole beds of garden mint, especially when growing in 

 damp, shady situations, are often completely destroyed by 

 this parasite, which also occurs on several species of wild 

 mint, and other Labiate plants. 



All three conditions of the fungus develop on the same 

 host. The orange aecidia or cluster-cups appear first in 

 the spring, and are most abundant on the stems, which 

 become swollen and much twisted and distorted. 



