Fiddlehead ferns are most definitely NOT poisonous. In fact, here in AK, they're known as a wonderful delicacy available only a short time each year. Their taste is reminiscent of asparagus and there is a sweet grassy aftertaste. Pick them and steam them soon after, for only a few minutes. Just make sure you've washed them thoroughly to get rid of any tiny bugs from the field. I like to add a little butter and just a squirt of lemon to them before serving. Some like a little balsamic vinegar instead of the lemon juice. Hope you'll try them- they're really wonderful.