Storing carbon in the prairie grass
Climate Solutions DAPHNE PRAIRIE, TEX. B.F. Hicks is doing 70 mph down a two-lane road in Franklin County, Tex. He pulls up in his truck to a gated property thats closer to Arkansas than Dallas. Waist-high bluestem grass sways in the wind across 922 acres that stretch out before him. The air is filled with dick-dick-see-see-see, the song that gives the dickcissel prairie bird its name. Welcome to Daphne Prairie, mostly flat grassland that has been in the Hicks family since 1839 and is one of the last unplowed prairies in Northeast Texas. Lying at the edge of prairie as it transitions into eastern forests, the land looks today as it did when settlers arrived in Texas before cotton was king and concrete was poured across the region. And Hicks, a 75-year-old lawyer who visits his property weekly in a bucket hat and jeans, is trying to keep it that way, hopeful that untouched grasslands in Texas and across the country can help mitigate climate change. Scientists say the world needs to cut greenhouse gas emissions nearly in half by mid-century to avert catastrophic effects from global warming. Carbon dioxide is the most prevalent greenhouse gas; the amount in the atmosphere has been rising as humans burn fossil fuels. Not only must the world stop releasing more carbon, some CO2 already in the air also must be removed, experts say. Thats where the prairie comes in. As part of photosynthesis, plants pull carbon dioxide from the atmosphere and store it in their stems, leaves and roots. Unlike trees, grasslands store most of their carbon underground, in their roots and the soil. And that makes them more reliable carbon sinks than forests, according to a 2018 University of California at Davis study . Because carbon is stored in the soil, it is not released back into the atmosphere when grasslands burn, as it is when trees go up in flames. A pristine prairie can also be home to hundreds of types of plants. Poets and explorers wrote about the spectacular view above ground, but the real magic is what happens below the surface. Its a good locker to put the carbon into, said Jim Blackburn, an environmental lawyer and Rice University professor. Carbon will stay in the soil for centuries." But there are few pieces of pristine land left like Daphne Prairie, untouched by plow or urban sprawl. [ Iowa farmers ripped out prairie; now some hope it can save them ] Less than 0.1 percent, or about 5,000 acres, remain of the original 12 million acres of Blackland Prairie that once spanned from San Antonio to the Red River north of Dallas, according to the Texas Parks and Wildlife Department. The trend is the same throughout the tallgrass prairie system that runs from the Texas coast north to Manitoba, making it one of the most endangered ecosystems in North America. To create incentives for landowners to preserve natural land, Blackburn and the Baker Institute at Rice are leading a group of organizations as varied as the Nature Conservancy and Valero Energy to brainstorm ways to create a market for storing carbon in the soil of prairies, farms, ranches and grasslands in Texas and around the country. Funding is available to landowners for carbon stored in forests, such as Californias cap-and-trade market, and the same should be done for soil, Blackburn said. The value of pristine grassland in the fight against climate change is not just its ability to store carbon, Blackburn said. Prairie grass helps the land recover from weather that is becoming more destructive as the planet warms, he said. Blackburn, the co-director of Rice Universitys Severe Storm Prediction, Education and Evacuation From Disasters Center, learned this while studying Hurricane Ike, which hit the upper Texas coast in 2008. The Bolivar Peninsula in Galveston and other inhabited areas were absolutely wiped out by storm surge that pushed 20 miles inland, Blackburn said. But native prairies and grazing land on the coast recovered quickly. If you are looking for a definition for the word resilience, it is these native prairie and marsh systems, Blackburn said. They evolved with storms. Storms are built into their DNA. Storms are not hard-wired into human DNA, except to run from them or the results they leave behind. Blackburn wondered how property owners could be persuaded to keep the land in its natural state to help bear the brunt of future storms. That would be the best long-term insurance policy on the Texas coast, he said. It was hard to identify anyone who would pay landowners to mitigate flood damage, Blackburn said. But carbon storage is another matter, particularly for oil and gas companies looking for ways to offset the carbon dioxide that they emit. All native grasslands in the country together could sequester up to 1 billion metric tons of carbon dioxide each year, Blackburn estimates. The nations annual carbon dioxide output was nearly 7 billion metric tons in 2018, according to the Environmental Protection Agency. The group led by Blackburn and the Baker Institute is working on a blueprint for a nationwide program to pay for carbon storage in soil. Landowners who enter such a program would agree to a 10-year commitment. If the land is sold, the commitment restarts. The amount of carbon retained in soil can be measured in a variety of ways. The earliest method was to put a soil sample in an oven at 500 degrees. At that temperature, organic matter is burned off and carbon can be calculated using the weight of what is left. Another rudimentary way of measuring is to bring a book of color palettes into the field and match the shade of the soil to estimate the amount of carbon. Land that has been not been tilled or overgrazed has the potential to sequester the most carbon, said Hal Collins, a microbiologist with the Agricultural Research Service of the U.S. Department of Agriculture. One acre of pristine prairie can store about 5 tons of carbon, he said. Soil scientists like Collins bring samples into a lab and use an instrument designed to measure organic matter. It basically does the same thing as the oven, but in a more controlled environment, he said. Carbon sequestration is also good for soil health, building up organic matter that has been depleted over the past 200 years because of plowing and the heavy use of fertilizer. A piece of land can recover, and store more carbon relatively quickly, with changes in cultivation, Collins said. Precision may be the key. With strip tillage, which means plowing only where a seed is placed, about 50 percent of the land is left undisturbed, Collins said. Targeting fertilizer to where its needed, as opposed to spraying it across a field, can also increase the amount of carbon in the soil. A payment system for carbon storage would be welcomed even by landowners who recognize the value of undisturbed soil. Keeping land wild costs money, whether its through actual upkeep or because of an opportunity lost. [ Climate change is bad for your beach vacation ] Hicks said he has spent $220,000 on gravel for three miles of roads around Daphne Prairie so he can get around easily to check for invasive species. The property has a maze of fencing with 16 gates to corral cattle that get loose from neighboring lands. He spent a few thousand on a barn and $2,500 for a thermal imaging scope for nighttime hunting of feral pigs, which tend to either eat or destroy Silveus Dropseed grass. Its all to protect the rare plants on the prairie. It costs a lot of money. But I havent had kids. I havent had kids in college, said Hicks, whose family struck oil in Daphne Prairie in 1936. This particular thing caught my attention. For the sake of nature, I feel real good about it. His godson first told Hicks about the lands potential for mitigating global warming. He decided shortly after to keep his land in a natural state for perpetuity and gave a conservation easement to the Native Prairie Association of Texas with plans to bequeath the land to the group. I hope my life can be judged on the merits of my personal decisions on the prairie and in my lifestyle in advancing practices to limit the forces threatening our planet, Hicks said. Other landowners are less committed. Every year, 2 million acres of farmland are lost to development in the United States, according to the Texas Farm Bureau. In February, an 80-acre prairie southeast of Dallas was cleared to make way for an industrial park despite some community pushback. Less than 40 miles north of that parcel, Steve Bolgiano has a deed to 50 acres of pristine prairie in Farmersville. He bought it in 1999 and it has remained vacant since. Before 9/11, he drew up plans to build a subdivision on it. Then he thought about creating an eco-resort. These days, he is leaning toward having a wedding venue on the property. Something to keep the original landscape intact, but also capitalize on it. Theres money in that view, he said. I mow yards for a living, Bolgiano said. Im not Ross Perot. I cant give it away for conservancy. I cant afford it. Thats why Blackburn is trying to get the ball rolling on a nationwide program. The first priority is weve got to get a market, he said. Landowners need to see that theres money to be made off of carbon in the soil.