Retailer aims to double the amount of locally grown produce it sells by 2015.
Environmentalists question assumptions behind Stanford study.
New survey suggested environmentally friendly products are a core lifestyle element for many consumers.
Including land-based carbon in greenhouse gas control strategies lowers costs and preserves forests, according to new study.
Newly released figures show that sales of organic products increased 17% in 2008.
The ongoing drought will idle 1 million acres and 60,000 workers at a cost of $2 billion in lost income.