Panic! I thought I could ignore them the first two years. Last year they were bad enough to cause poor ripening on some vines.
I've been fighting them for three years. I've tried to be nice and used various organic oils. As it is early, I'd clean out below the rows. Supposedly the buggers nest in the litter on the ground. If you spray now, you might cut them off. Typically we get three hatches a summer in Washington. Lots of nasty sprays at HD and Lowe's.
This spring I'm raking out the bottom of the rows and I'm going to spray with a systemic soil drench, Imidacloprid. I hate the idea of what it is going to do to the bugs in the soil, but WSU says it isn't too bad and after 30 days nothing in the grapes. Hopefully compost will help build it back up.
As a back up I've also purchased some PyGanic to spray. It is labeled organic, derived from chrysanthemums. It is hard on bees though, so that is why I'm starting with the systemic. Orchard neighbors wouldn't appreciate an attack on the bees.
You are way ahead of me, I still don't have bud break, thank goodness it was 34 yesterday morning.
Keep me posted on what you do and what works!