LUBBOCK, Texas – Soil which is moist and loose and rich in organic matter is generally the textbook appearance of a healthy soil. However, in many arid parts of the country, this type of earth can be hard to come by. Finding a way to improve pasture growth in dry and stressful environments is why researchers from the Soil Science Society of America set about to see how to make these ideal conditions most anywhere. What they found was a solution in the form of cow manure.

“We know that planting perennial grasslands for cattle production can help protect and restore soil in semi-arid lands that are likely to erode and degrade from intense farming,” said Lindsey Slaughter, an assistant professor at Texas Tech University and a member of the research team. “But producers need additional ways to increase soil carbon and nutrient stores.”

Published in the Soil Science Society of America Journal, the study found that manure helped increase organic carbon and the number of microbes in the ground, both two important characteristics of a healthy soil. In the study, the team applied a low one-time amount of manure to two types of pastures. The pastures they put the manure on had either grass only that was fertilized occasionally or were a mix of grass and legumes that was not fertilized.

Although, the process took time, the researchers discovered that the pastures receiving fertilizer in their trials responded best to the fields containing manure. They believe this is because the nitrogen in the fertilizer helped the microbes decompose the manure better. Slaughter said that manure has already been proven to assist cropping fields with growth and that the team wanted to try the same premise on pasture management.

“Improving the soil’s ability to perform these roles and support plant and animal life is our target for soil health,” she said. “Adding the manure can provide a boost of material that can be incorporated into soil organic matter. This helps provide a stronger foundation for more microbial activity and nutrient cycling.”

At their plots in Texas’ Southern High Plains, the pastures took about a year and a half to see significant changes, however, Slaughter said that she wasn’t surprised by the extended time.

“This tells us that it can take a long time for even a little added compost to become incorporated into the soil organic matter of semi-arid grasslands, but it definitely helps. We think this is mostly due to the dry climate at our study site. We commonly get little rainfall per year. The microbial community was not able to work quickly or efficiently to decompose the manure without water.”

Slaughter adds that the next steps in this work include whether more manure or multiple applications would get faster results. In addition, they hope to investigate if irrigation or fertilizer would help incorporate the manure faster.

“We need more research along these lines to help us design strategies that quickly and effectively increase soil health and productivity in these grasslands,” she said. “This helps farmers save money on nutrients and amendments while building soil organic matter and nutrient cycling capacity. This also saves them water and protects against soil degradation.”