As the balance of the earth's resources shrink, amidst higher human consumption and growth in world population, technology alone will not supplant extractive resources quickly enough to replenish the planet. Suddenly, a new perception is taking hold - the frontier of greatest economic opportunity is with those enterprises that do the following:

Put more into the earth than they take out. Reduce carbon emissions whose future costs are steep. Gain shareholder value through sound environmental practice. Exercise entrepreneurial responsibility to meet resource shortages, and embrace natural capitalism over industrial capitalism.

In June of 2011, Norfolk Southern Railway made the largest forestry carbon investment to date in North America. They are planting 6.04 million trees for 1.12 million tons of carbon credits over five years through GreenTrees and C2I of Middleburg, helping to restore America's Amazon, the Mississippi Alluvial Valley. Unlike other forestry-offset types where an accounting change on the land must take place in order to generate credits, reforestation builds equity back into the land.

According to the US Forest Service, planting a single tree creates the following value over 50 years:

• Generates $31,250 worth of oxygen
• Provides $62,000 worth of air pollution control
• Recycles $37,500 worth of water
• Controls $31,250 worth of soil erosion

The total value of a single tree is $162,000 of value. Norfolk Southern will be creating from 6 million trees nearly 1 trillion of value over 50 years. This value creation and ecological impact is a result of the role of carbon as a guarantor of forest permanence, where a tree is worth more up than down.

From a corporate perspective, Norfolk Southern's investment will result in the following metrics:

• 211 trees per employee ($34m of value per employee over 50 years)
• 299 trees per track mile ($48 million of value per track mile over 50 years)
• 1450 trees per locomotive ($235 million of value per locomotive over 50 years)

Norfolk Southern thinks long term. Their leadership is prompting other large corporations to reach out to GreenTrees about similar investments.

"This is a true triple play; a perfect blend of environmental, economic and social benefits," states Blair Wimbush, Norfolk Southern's Corporate Sustainability Officer. "It demonstrates Norfolk Southern's lasting commitment to environmental stewardship. We're in this for the long run."

Trees and Trains is the story of conservation with a purpose, and capitalism with a heart. At the heart of the intersection are industry and the environment working with each other. Bringing private capital into conservation forces the conservation mind-set to look to returns --- both economic and environmental. This blended return is a powerful and dynamic proposition, enabling a wider net of available dollars available to create impact.

A sustainable investment is a good thing. But a sustainable investment that is hooked to a sustainable investment process becomes a force for exponential change. These are the fundamental design elements of Natural Capitalism.