Here are some fun facts from http://www.newton.dep.anl.gov/natbltn/300-399/nb316.htm

"There are two general classes: the White Oak group, and the Red Oak
or Black Oak group. In the first, the ends of the leaves and their lobes
are rounded without any spines or bristles at the tips. Their acorns,
which are relatively sweet and edible, mature and fall off the same
year they are formed, so that there are none on the branches in winter.
In the Red Oak or Black Oak group, the leaves and their lobes, if any,
have bristly hairs or spines at the tips. The acorns, which are bitter
with tannin, do not mature and fall off until the second year, so that
small ones may be seen on the branches in winter."

Okay, so, what that means to me is that Quercus alba isn't the only White Oak on the Block. Good thing, cause all I got around my house are Quercus virginiana, Quercus macrocarpa, and Quercus prinoides. <img src="/images/graemlins/smile.gif" alt="" /> I always meant to attempt eating the acorns. Spent hours researching it and drawing up a plan of action for the task, but never actually got around to it. Then, one day, my 9 year old neighbor was helping me weed the garden and got bored, started gathering acorns, and announced that she'd learned in school that native americans used to eat acorns. One minute I was telling her that native americans are not past-tense subjects, and the next minute I was observing that although hitting it with a rock was not enough to crack the shell, "does you mother mind you using a hack saw? I think I'd better do it." Then, we were boiling them in water and eating them. Funny how plans get carried out . . .

Anyway, to wrap up my long winded reply, it's a good idea to identify the trees in your area. If a book isn't helpful enough (oaks have a way of cross breeding themselves and defying the identification guides) ask around. Maybe there's a natvie plants research center nearby, or a biology professor, or your neighbor may be a professional landscaper . . . When you know what the tree is, it's easy to find out if you can eat the acorn. And looking up
Quercus prinoides on the internet is a lot easier than waiting all winter to see if the acorns are still there. <img src="/images/graemlins/smile.gif" alt="" />

But they're all edible, more or less. It's just that the white oak acorns are "minute rice" and the red oak acorns are "soak overnight, changing the water before cooking".

They tasted like blanched almonds.