United Kingdom 
my Forsythia has some sort of growths attached to the stems
18 Aug, 2012
Answers
Had the same thing and just pruned the affected branches as they were very unsightly and weighed the branches down.
19 Aug, 2012
They sound like some sort of gall, they do no harm to the plant, just look a bit unsightly, you can cut them off when you prune next year after flowering, Derek.
18 Aug, 2012