"Community-supported agriculture, a form of an alternative food network, (in Canada Community Shared Agriculture) (CSA) is a socio-economic model of agriculture and food distribution.

A CSA consists of a community of individuals who pledge support to a farming operation where the growers and consumers share the risks and benefits of food production.

CSAs usually consist of a system of weekly delivery or pick-up of vegetables and fruit, in a vegetable box scheme, and sometimes includes dairy products and meat."
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"Typically CSA farms are small, independent, labor-intensive family farms. By providing a guaranteed market through prepaid annual sales consumers essentially help finance farming operations. This allows farmers to not only focus on quality growing but can also level the playing field in a food market that favors large-scale, industrialized agriculture over local food."
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"CSA members purchase only what the farm is able to successfully grow and harvest sharing some of the growing risk with the farmer. If the strawberry crop is not successful, for example, the CSA member will share the burden of the crop failure by receiving fewer, or lower quality, strawberries for the season."
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"The environment’s benefit is quite simple- the minimal transportation required to transport food locally is a significant reduction of carbon dioxide emissions. Many CSA farmers also produce their food without the use of pesticides or inorganic fertilizers, so they are as natural as possible, limiting their impact on the environment."

wiki link:
https://en.wikipedia.org/wiki/Community-supported_agriculture

one of the biggest community with 13,000 subscribers:
https://en.wikipedia.org/wiki/Farm_Fresh_To_You

docu film:
https://en.wikipedia.org/wiki/The_Real_Dirt_on_Farmer_John