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Vast acreages of unplanted land can be planted in trees, e.g. interstate highway medians. Today these lands are just being mowed or ignored.



In the US alone it is not hard to find 1 million acres of idle land that grows grass today and is being maintained by mowing.  We have all the infrastructure needed to grow more seedlings and plant these acres in trees - some are very fast growing.  This is an obvious no brainer, but no one is talking about it or doing it.  Median strips on interstate highways are an easy example.  Some of them are already forested - so no one can claim it is a safety hazard or can't be done.  But planting trees on a million acres in the US and easily 10 million acres worldwide is straightforward.  This doesn't require a huge investment or any new technology.  It is low risk and readily done with existing equipment and manpower.  Some investment in expanded seedling nurseries and related infrastructure is needed, but it is pretty straightforward and many nurseries have the space to do it already.  The end result of course will be large amounts of carbon sequestration.

Papers have been published estimating that it will take the planting of over 100 million acres to requester a billion metric tons of CO2 per year.  This is a large number and very difficult to achieve just in the US.  But a 10+ million acre goal for the US may well be achievable and the remainder will need to be found in other countries around the world.

The proposed strategy would be to start in the US with a 1 million acre goal and perhaps one or two other countries as the proof of concept.  We would then take those learnings and apply them as appropriate to other countries where the land use opportunities are most promising and the political climate is most favorable.

Is this proposal for a practice or a project?


What actions do you propose?

The "easy" start is to have the federal government mandate planting trees along the sides and in the median strips of the interstate system and other federal divided highways.  States would follow next with their four-lane or wider divided highways.  Then you move on to other public lands in the BLM, parks, and idle lands that could be planted.  On the private side, give transportation companies like the interstate gas pipeline companies tax incentives to plant their right-of-ways.  Incentives through the income tax code, the Natural Resources Conservation Services Environmental Quality Incentives Program (EQIP), and other channels could be made available to individual landowners to plant small plots as well as large acreages.  Where farmers are now paid to not plant fields, perhaps similar incentives could be applied if they planted them in trees.  The list goes on and on.  I haven't run the detailed numbers, but I know it isn't had to have these numbers add up to a million acres in the US and most likely many times that number.  Internationally the numbers get even bigger.

I just read an article talking about the difficulties in Iceland of resurrecting their vast forests that completely eliminated a thousand years ago by the Vikings.  Hard to do, but here is one example of a country working to be a part of this solution.

Who will take these actions?

The appropriate governmental bodies need to provide the right incentives (e.g. tax breaks) and then let the land managers do the work.  The work can be mandated for public lands by the Congress and state legislatures.  Incentives will be required to make it happen on enough private lands.

This proposal envisions the creation of a non-profit that will lobby with both the legislatures and the land managers to get the right incentives and mandates in place to make this happen.

Where will these actions be taken?

The US will be the pilot.  One or two other promising countries will also be started early on to obtain more learnings to help move the program to a worldwide footing.  The trees to be used should be native to the locations, fairly fast growing and long lived.  In the country selection below I only selected the US because I haven't the time to determine which countries are the next best choices.

Note that the focus is on what is known as afforestation, not reforestation.  Afforestation refers to planting idle lands, whereas reforestation is planting forested lands that were just cut.  Reforestation may also get included in this program, but the initial focus will be on afforestation.  An EPA study in 2005 showed that afforestation results in the largest amount of carbon sequestration of any of the alternatives that were studied, including reforestation, improved grazing management and various other practices.  Afforestation was estimated to sequester 2.2 to 9.5 metrics tons of CO2 per acre per year.

In addition, specify the country or countries where these actions will be taken.

United States

Country 2

No country selected

Country 3

No country selected

Country 4

No country selected

Country 5

No country selected


What impact will these actions have on greenhouse gas emissions and/or adapting to climate change?

The research I have seen indicates that it would take at least 100 million acres of afforestation to sequester 1 billion tons of CO2 per year.  if we were to win a $10,000 prize in this program, it would be used as the seed money to refine our proposal and program and to seek the required support and backing to launch a non-profit to pursue this program.

Whether this program succeeds in causing the planting of 1 million acres or hundreds of millions of acres, it will generate benefits and cause more and more people to take actions that will also help.

In the few weeks I have had to work on revising this proposal, I have been totally consumed with running another environmentally focused program that seeks to preserve our eastern forests from the serious and accelerating threat of destruction from nonnative invasive plants.  See  October is our busy season and I have had zero time to focus on this proposal.  If I move to the finals, I should have more time to devote to this.  Tomorrow is actually the last or our true busy season commitments, then the pressure eases.

What are other key benefits?

In addition to sequestering carbon, the costs would be partly offset by reduced maintenance costs and a reduction in fossil fuels used to mow and maintain the grass that is there now.  Median strips full of trees will also provide aesthetic benefits and be a natural blocker for on coming vehicle lights at night.  In the long term some areas may be harvestable and become another source of fiber, wood, and other products.

There would be a host of other side benefits including:

- Cooler temperatures - note that temperatures in forested areas are lower than in open spaces

- More tree planting in urban and suburban areas will bring improved aesthetics and better outdoors experiences

- Note that when wood is cut and used as lumber, the carbon remains sequestered.  So to the extent this program increases the wood supply, lowers the price of lumber, it will increase the long term sequestration on carbon in wood used for construction.

- Increased focus on large scale tree planting will also provide more incentives for research to improve the quality of the seedlings to make available faster growing trees or trees with qualities that maximize the amount carbon sequestered.


What are the proposal’s projected costs?

The costs are quite modest and partly offset by a reduction in long term maintenance.  Negative side effects are minimal - note that thousands of miles of roads are already forested - so adding forests to highways is nothing new and people know how to manage them.  The biggest challenge is getting the governments to move and make the required changes.

The work itself is not hard and can be done fairly quickly.  As the demand for seedlings grows, more nursery space and production will be required.  Seedlings are fairly inexpensive today and increased production may well yield lower costs per unit.


Depending on the tree species used, there will be meaningful sequestration 5-10 years after planting with the bulk of the benefit to occur in the 10-50 year range.  Benefits will continue to accrue for the longer term as well.

About the author(s)

Rod Walker owns 2,000 acres of forestland and has planted thousands of trees.  He also has 2 masters degrees from MIT - in computer science and finance.  He was the CEO of a well known private company working in big data.  He sold the 700-person company to HP before he retired.  Now he runs a non-profit focused on reducing the impact of invasive plants across 3 million acres of Virginia along the northern Blue Ridge.

He would be one of the drivers of the new non-profit that would be created to implement this program.

Related Proposals

I don't know if anyone has ever proposed anything related to this.


If you accept this proposal, we will put in the effort to take it to the next level.  See the May 4, 2009 report written by Ross W. Gorte written for the Congressional Research Service entitled US Tree Planting for Carbon Sequestration.  It is 7 pages long and a quick, easy read.