But some environmental groups say palm oil cannot be produced sustainably at reasonable prices.

Choosing sustainably produced native timber is reasonable, but it is even better to buy something second-hand.

This label allows the consumer to know that the product was produced sustainably.

Dedicated energy crops, such as switchgrass, are also promising cellulose sources that can be sustainably produced in many regions.

And though "sustainably produced foods may cost a bit more, many of their potential beneficial environmental and social impacts are already included in the price."

They run their school bus on 100% biodiesel that is sustainably produced from waste vegetable oil.

From April 2015 only sustainably produced timber will be purchased.

The Ark is designed to preserve at-risk foods that are sustainably produced, unique in taste, and part of a distinct ecoregion.

Dedicated energy crops are promising cellulose sources that can be sustainably produced in many regions of the United States.

In the US, about 1.4 billion dry tons of biomass can be sustainably produced annually.