They are not always showy. There may be large amounts of them in one spot, so that they appear plentiful. There are some good picture books available. All folks who pick plants from the wild should try to familiarize themselves with the local protected plants. When in doubt, don't pick it.
Some plants are sensitive to disturbance.
Please do not pick them even if they aren't protected. The Calypso Orchid, Calypso bulbosa , is a fragile plant that lives partially off leaf mold. Its little root is close to the surface, and easy prey to slugs and others. Minor disturbances can easily dislodge the root from the mold. Even disturbing the area around it during flowering could kill it.