Forest carbon credits for state landowners

STARKVILLE, Miss. -- Carbon dioxide is the most commonly produced greenhouse gas, the substances that trap heat in the atmosphere keeping the planet warm enough for life.

Carbon is stored in high amounts in timber, of which Mississippi has an abundance. The state ranks in the top 10 nationally in timber production, with close to 20 million acres of timberland.

The U.S. Geological Survey says that carbon sequestration is the process of capturing and storing atmospheric carbon dioxide. Removing carbon dioxide from the atmosphere reduces the potential for global climate change.

Since timber stores carbon efficiently, a tremendous amount of the greenhouse gas carbon dioxide is stored in Mississippi’s forests. This makes timber a valuable resource in efforts to limit the amount of carbon available as a greenhouse gas.

Carbon credits and the carbon offset market have made an impact on Mississippi’s economy to a degree for about 20 years.

The carbon market is highly complex and often relies on large tracts of timberland being locked into carbon contracts for decades. Mississippi landowners have been able to take advantage of some of these contracts, and in the past, short-term options existed for owners of small tracts of land.

Curtis VanderSchaaf, a forestry specialist with the Mississippi State University Extension Service, knows it can be difficult to understand the carbon market and the amount of carbon sequestered in timber. He recently made some careful calculations to estimate the amount of carbon contained in pine logs on a fully loaded log truck.

“This is an initial step to determine what is the net carbon footprint per truckload of pine logs given the carbon stored in the wood versus the diesel usage of the truck itself and other timber harvesting vehicles,” VanderSchaaf said.

He began by looking at the different types of log trucks and the loads they each can carry, coupled with state laws on weight limits. For an example, he assumed a 59,000-pound payload per truck, which is 29.5 tons of pine logs.

“If this is green weight, simplistically, you can assume dry weight is 50% of green weight and carbon is 50% of dry weight,” he said. “That means there is 7.38 tons of carbon per load of pine trees, or the equivalent of 24.5 metric tons of carbon dioxide.”

While trees that have been logged are sold for timber, delaying harvest and letting them grow keeps the carbon sequestered in the trees, giving the standing timber a potential value to the carbon market. Many carbon markets essentially pay forest owners not to harvest their trees for a set amount of time.

“Many carbon markets work by paying forest owners to delay harvest,” VanderSchaaf said. “This keeps the carbon stored in timber, but by delaying harvest, it means landowners have delayed timber revenues. Carbon payments are intended to help compensate for the delay.”

A key concept of carbon markets is additionality.

“Additionality refers to carbon sequestered and stored beyond what would have happened if the landowner had not enrolled in the market,” VanderSchaaf said.

All forests sequester carbon until they are harvested. Landowners enrolled in certain programs can receive additionality payments for sequestering more carbon than would have been sequestered under “business-as-usual” practices.

VanderSchaaf said buyers in the carbon market have traditionally been large industries such as steel and energy production that have government requirements to reduce greenhouse gas emissions to meet air quality goals. Large private companies such as Amazon and Disney were the next to enter the carbon market as buyers.

“These companies are allowed to offset their greenhouse gas emissions by buying carbon offset credits from forest landowners who are sequestering additional amounts of carbon in their forests,” VanderSchaaf said.

Because the demand for carbon offsets from these large companies and industries was very large, often only significant tracts of forestland were considered for long-term contracts in the carbon market.

“In some cases, carbon programs would aggregate acreages of many smaller landowners to produce an economically viable contract,” he said.

This extra level of coordination and work resulted in additional fees, reducing the amount of revenue each individual landowner received.

“In recent past years, small-scale Mississippi landowners were able to take advantage of one-year contracts through the NCX program, generally at a lower revenue because of the short term,” VanderSchaaf said, referring to the National Capital Exchange.

These forest carbon credit programs are currently not available. One reason is concern over whether carbon sequestered under the one-year contracts had a permanent and lasting impact on greenhouse gas reduction.

“Although NCX’s one-year contract forest carbon market is no longer, other projects still exist and landowners continue to express some interest in forest carbon markets, programs, and projects,” VanderSchaaf said.

VanderSchaaf said there are currently five general types of forest projects that result in additional amounts of carbon being sequestered and accepted for producing carbon offset credits.

Afforestation/reforestation restores tree cover to non-forested land, and often involves high costs due to planting, seeding or the use of acorns. The second type is avoided conversion, which prevents conversion of forest to non-forest land, but must demonstrate the forest is at significant risk of conversion.

The third type of program is improved forest management, and this involves management activities to maintain or increase current carbon stocking levels. Examples include increasing rotation age, competition control, thinning treatments and improved stocking levels.

Select cut above baseline -- or some other threshold -- is the fourth project. VanderSchaaf said a baseline is often determined at the time of enrollment, and yields above that baseline can be harvested and sold by the landowner.

A final project is deferred harvest, which results in an additional amount of carbon on the landscape for a limited time.

The different voluntary forest carbon market programs that exist in the U.S. typically are based on one or more of these carbon credit calculation methods.

MSU Extension has a variety of information available on this topic. Find Publication 4145 Voluntary Forest Carbon Markets and Programs for Mississippi Landowners at https://extension.msstate.edu/publications/voluntary-forest-carbon-mark….