[pct-l] plant guides

[davedesign at yahoo.com (Dave Blumenthal)]

Hi folks!  I'm a botanist from the East Coast and am planning on hiking the 
PCT in 2004.  I am not familliar with west coast plants at all, and I know 
that it will drive me crazy not to be able to identify anything while I'm 
on the trail.  So I'm looking for comprehensive and scientific (preferably 
with a dichotomous key) but light weight botanical guides that cover the 
regions that the trail crosses.  I consider this to be my one "luxury" 
item.  Since I'm hoping to keep my base pack wieght under 13 pounds, 
clearly the Flora of California (a veritable door stop) is not a good 
choice.  Does anyone have any suggestions?

Thanks!

Lexi