after blooming in may brunnera leaves turn black. I assumed it meant the end of their seasonal cycle. now I wonder if it is a fungus that repeats year after year and, if so, can it infect other plants nearby. this year june 2013 I have removed most of the plant and put out in trash.my question is - is this normal for the end of their season or should I assume infection and remove altogether. i'm getting to the point where is a plant presents an ongoing problem with pest/disease I get rid of it.