<human>: My Old English Sheepdog is almost 18 months old and suddenly there's hair everywhere.  Up until now, shedding has been really rare.  I first noticed it about the same time I noticed the silver coloring appearing beneath her black patches; probably within the last month or two.  Now she'll shake and a cloud of hair just goes everywhere.  My bed is covered with it.  I'm constantly cleaning it from her crate. At work I'm always pulling those long strands off me. Sometimes I find it in balls.  If I tug at her I'll come away with a handful of it. 

It's not so much that it's a nuisance; just that it seems to have happened suddenly and has me concerned.  I see no signs of anything in the way of mites or mange and she's free of fleas and ticks.  There are no bald patches and there is no visible skin irritation.  I've clipped her once late last spring but she has since fully grown out.  The only visible change is her coloring. 

Could this have anything to do with her coat developing or is this just the beginning of something that will be with her from here on out?

Give me the gist of the text in a nutshell
<bot>: From puppy until about 16 months there has been almost no shedding.  Now there's hair everywhere and I'm worried.