WITCHES' BROOM ON BLUEBERRY 



These odd malformations, popularly known as witches' brooms, are often caused by the presence 

 of fungous diseases of the type known as the rusts. The presence of the fungus causes tne 

 branches to appear in the form of a dense cluster, somewhat resembling a broom, i ne 

 rusts frequently attack trees, sometimes producing enormous witches brooms wliicn are 

 erroneously called crow's nests. It is interesting to note that the rusts usually require 

 the presence of other plants in order to complete their Hfe cycle, eadmg what might be 

 termed a double life. In this case the other plant necessary for the development ot the 

 disease is the balsam fir, where the fungus takes on an entirely different form. (l^ig. o.; 



