What is the primary characteristic of a weed?

The primary characteristic of a weed is that it is a plant that grows where it is not wanted, often competing with desired plants for resources. Weeds are typically opportunistic species that thrive in disturbed soils or areas where other plants are cultivated. Their presence can lead to competition for vital resources such as water, nutrients, and sunlight, which can negatively impact the growth of desired landscaped or agricultural plants.

This trait of being unwelcome and competitive is what sets weeds apart from other plants, as even a desirable plant can become a weed depending on its location and the context in which it is growing. Understanding this definition is crucial for landscape management and implementing effective weed control strategies.