In case you want to go on a spring backpacking trip, the Sierra Club has a backpacking trip to Rancheria Falls coming up. You don't have to be a Sierra Club member (but why wouldn't you be?).
I'm not sure if there are still spots left (I myself am not going)
May 19 · Sat through May 20 · Sun · Backpacking Section
Rancheria Falls, Yosemite NP 1CT Backpack. Rancheria Falls bursting with spring melt cascading into Hetch Hetchy Valley and the mighty Tuolumne River calls from the mountain crags to join Lloyd Sawchuk, JoAnne Lauer and Aleta Beaupied on this individual commissary classic spring adventure. Contact Lloyd for details. Leader: Lloyd Sawchuk
Contact info on page below
http://sanfranciscobay.sierraclub.org/chapter/events/calendar.asp