Weed Control Alternatives (Source)
What do weeds tell us? (Source)
Many individuals view weeds in their yard or garden as negative because we have been raised to believe they are unappealing. When the truth is, every weed has its own purpose and tells you specific things about the soil.
Dandelion (Taraxacum) indicates well-drained soil. They also have the ability to transport calcium, iron and other minerals from deep soil to the top due to their taproots.
Bindweed (Convolvulus) and buttercups (Ranunculus) indicates poor drainage
Chickweed (Stellaria) indicates tilled, fertile soil. When decomposed chickweed also releases potassium, phosphorus and manganese into the soil.
Clover (Trifolium) indicates low fertility soil and low amounts of nitrogen present. Clovers also have the ability to obtain nitrogen from the air and bind the nitrogen to the components of the soil.
Horsetail indicates that your soil is low in line, sandy, light and acidic. Horsetail overtime accumulates silicon, magnesium, calcium, iron and cobalt and discharges them during decomposition.
Plantain (Plantago) indicates heavy compacted acidic soil. When decomposed plantain helps to deacidify the soil.
Quack Grass (Agropyron reopens) indicates a crusty surfaced soil that is poorly drained. Quack grass can also be used as an insecticide because ti causes nerve damage to slugs and if chopped finely it helps repel them.
Sorrel (Rumex) indicates that the soil is acidic and is a low lime soil. Sorrel helps calcium and phosphorus reach the top of the soil allowing it to alkalinize.
Thistle indicates that the soil is heavy and compacted.
Vetch (Vicia) indicates that the soil is low in nitrogen and fertility.
Canadian Advocates Against Pesticides