Dennis Calmer - Unkraut 08.03.2014

Unkraut German for pest plants - is natures opposition to the
leadership of gardeners. Unkraut is an every day term used to
describe a plant considered undesirable. The word—commonly applied
to unwanted plants in human-controlled settings, such as farm
fields, gardens, lawns, and parks—carries no botanical
classification value. Indeed, a number of plants that many consider
Unkraut are often intentionally grown in gardens and other
cultivated settings. The definition of Unkraut is very much in the
eye of the beholder. Some plants are generally viewed as Unkraut.
That's wrong, because the same species can be a medical herb or a
useful plant.