ok...... In rural areas, fiddleheads are harvested by individuals in early spring. When picking fiddleheads, three tops per plant is the recommended harvest. Each plant produces seven tops that turn into fronds; over-picking will kill the plant"
Ok so I guess you won't harm the fern plant itself if you don't pick all the heads.....but this I didn't know:fiddleheads have more antioxidants than blueberries. If you could eat fiddleheads all year round, and not be struck by a bus, you would live forever.