I had once heard that yucca blossoms were edible, and that in fancy schmancy resturants out in California, you paid good money to eat them in salads. I even Googled them, but didn't really find much information to satisfy my curiosity-some long gone trendy diner menus, and some Indian dude touting the cool factor of the Plains Indian diet. That was about it. What I did find told me to be sure not to eat anything but the blossom itself, as yucca contains saponins (which I understand to be a form of soap, and as such, quite bitter and narsty.) Indeed, an Indian acquaintence of mine once swore up and down the very best shampoo in the whole world came from washing with the root of yucca. But I digress.
In June, the whole area around Spearfish burst into blossom and the yucca was everywhere. So I stopped and picked a spike. If you decide to try this next year, please don't be the ass I was, bring yourself some gardening shears to sever the spike from the plant. It's very very tough when using your car keys to cut it.
One spike will provide an ample amount of blossoms for about 6 people. I found that my favorite part was the bud, or the pistil and area fo the flower where the little embryonic seeds rest -it's quite sweet. I would liken the taste to that of a snow pea. We ate our salad with a lemon, basil and garlic dressing that was really outstanding.