Found all over the world, bracken is represented by various subspecies that differ in minor details. Coarse, much-divided fronds rise directly from deep, running rootstocks; plant grows from as low as 2 feet high to as tall as 7 feet under good conditions. Occurs naturally in many places and can be tolerated in untamed gardens, but beware of planting it: deep rootstocks can make it a tough, invasive weed. Do not gather fronds to cook as fiddleheads, since they contain a slow poison. Deer avoid these ferns.