Weeds are defined by their ability to negatively affect crop yield or other desired plants, causing economic or ecological harm.

Crop rotation is a farming practice that involves rotating different crops in a sequence to improve soil health and reduce the buildup of pests and diseases. While it can help manage weeds, it is not a direct method of weed control.

Allelopathy is the process by which plants release chemicals into the environment that can inhibit the growth of other plants, including weeds.

Dodder is a parasitic weed that attaches itself to other plants and steals their nutrients, causing reduced growth and even death.

Herbicide resistance is the ability of weeds to tolerate or survive herbicide applications that would normally kill them. This can occur through genetic mutations or other evolutionary processes.

Hand weeding involves manually removing weeds from the soil, either by pulling them out or using a hoe or other tool.

Dispersal is the process by which weeds spread their seeds or other propagules from one area to another, often through wind, water, animals, or human activities.

Biological control involves introducing natural enemies of weeds, such as insects or pathogens, to reduce their populations.

Tolerance is the ability of some plants to withstand the negative effects of weeds, such as competition for resources or allelopathic chemicals.

Crop rotation is a cultural method of weed control that involves rotating different crops in a sequence to disrupt the life cycle of weeds and reduce their populations.

Competition is the process by which weeds and crops compete for limited resources in the environment, such as water, nutrients, and sunlight.

Mechanical removal involves physically removing weeds from the soil, either by hand weeding, mowing, or using other tools or machinery.

Mycorrhizae are symbiotic relationships between plants and fungi that help the plant absorb nutrients from the soil, which can give them an advantage over weeds in nutrient-poor environments.

Herbicide application involves using chemical substances to kill or inhibit the growth of weeds.

Competition is the process by which weeds and crops compete for limited resources in the environment, such as water, nutrients, and sunlight. This competition can reduce the yield or quality of crops.