Besides hayfever, what do weeks of rain followed by blue skies and balmy weather bring to Sacramento? Wildflowers, of course. There are preserves in the area where you can see rare, native wildflowers.  But for people who are taking a walk along the American River Parkway or just poking around in the backyard,  here are four wildflowers you are almost sure to enoucounter.  (The common name of the flowers are linked to hi-res photos) 1.  Shepherd's purse (Capsella bursa-pastoris)  This pretty weed is a great wildflower to point out to children.  It's unmistakable seedpod appearently looks like a shepherd's purse, but to our modern eyes it looks like a valentine's heart.  The child will