smother crop

{{Short description|Crop used to smother weeds}}

File:Cultivo de alfalfa en el valle del Chubut 11.JPG is used as a smother crop.]]

A smother crop is a thick, rapidly growing crop that is used to suppress or stop the growth of weeds which have better root systems that help them compete with weeds for water and as a result, the root systems of weeds get weak. Meanwhile, the dense top growth of the smother crop suppresses the top growth of weeds. Effectively, smother crops successfully compete with weeds for vital resources (growth, space, water, light) and inhibit their germination and growth.{{citation |title=Definitional Glossary of Agricultural Terms, Volume 1 |author= Dinesh Kumar |publisher=I. K. International Pvt Ltd |date=Aug 20, 2008 |page=252}} Once the smother crop has served its purpose, it is ploughed under along with the weakened weeds, thus providing green fertilizer.{{citation |title=Growing Food: A Guide to Food Production

|author= Tony Winch |publisher=Springer Science & Business Media |date=Sep 27, 2007 |page=54}}

A good smother crop must compete strongly with weeds but minimally with the crop. Smother crops reduce dependence on chemical weed control,{{citation |title=Alfalfa and Relatives: Evolution and Classification of Medicago |author= Ernest Small |publisher=NRC Research Press |date=2011 |page=13}} and are sometimes used in the transition to organic farming.{{cite journal |last1=Wedryk |first1=Stephanie |last2=Cardina |first2=John |title=Smother Crop Mixtures for Canada Thistle (Cirsium arvense) Suppression in Organic Transition |journal=Weed Science |volume=60 |issue=4 |year=2017 |pages=618–623 |issn=0043-1745 |doi=10.1614/WS-D-11-00140.1|s2cid=86637263 }}

Secondary benefits of such crops include helping nitrogen fixation in soil (if legumes are used) and reducing soil erosion.

Alfalfa, hemp, rye, buckwheat, sorghum, Sudan grass, foxtail millet, sweetclover, marigold, silage corn are some examples of smother crops.{{citation |title=Weed Management for Developing Countries |chapter=Cultural practices for weed management |author= M. D. Shenk |publisher=Food and Agriculture Organization of the United Nations |date=1994 |page=166}}