Weed

This article is about the plants called weeds. For the drug, see Cannabis (drug).

A weed is a plant that people think is bad, because it is growing in the wrong place. Only smaller plants are often called weeds.

Dog violet (Viola labradorica), which can be a common weed.

A person may grow a plant because it has beautiful flowers, but other people may think that this plant is a weed for some reason. This may be for one of these reasons:

• It has pollen that makes them sneeze,
• It spreads seeds that will grow quickly,
• The roots go too far under the ground and can cause damage to houses or pipes,
• The roots spread quickly,
• The plant has poisonous berries,
• The plant has liquid (sap) in it that can hurt a person's skin,

If someone is farming a plant and it then moves outside the farm, the plant may then be called a weed.

Some plants are very hard to stop once they start growing. These are called invasive weeds.

Weed is also a name for any wild plant, one that people do not use for anything.