World News – AU – California remains a powerhouse of almond production

2. December 2020 – Almonds are a popular healthy snack and a staple on grocery store shelves around the world. More than 80% of these almonds are grown in California. As a permanent crop, almond trees have special needs and challenges for farmers.

Sat Darshan Khalsa, a member of the Soil Science Society of America, studies how almond trees use the key nutrient nitrogen. He recently presented his research results at the ASA-CSSA-SSSA 2020 virtual annual meeting.

« These plants are an interface between agricultural and forestry ecosystems, » explains Khalsa. “Similar to annual cultivation systems, permanent deciduous crops such as almonds are cultivated intensively. You get a high fertilizer and water input with high nutrient output. ”

At the same time, plants such as almonds are cultivated under no-till conditions in which the soil is only minimally disturbed. Soil tillage or digging of any kind would disturb the roots of the trees. In addition, almond trees shed leaves, wood tissues grow, and go through other processes similar to the trees in a real forest. These all have an impact on carbon, nitrogen and other nutrient cycles.

These properties can often cause nutrients to drain from the field. They can enter areas such as aquifers, where they can affect drinking water supplies to rural communities. Khalsa’s work tried to minimize this problem.

« Nitrogen is the primary nutrient tied to productivity, » he says. “At the same time, it is an important pollutant that affects air and water quality. Through our work, we can show that many California almond farmers are in a good position to remain highly productive. At the same time, they can protect or even improve the quality of the environment. ”

Khalsa and his colleagues specifically examined a concept called nitrogen use efficiency. It helps farmers to get enough nitrogen into a field and protect the quality of the environment. In their research, they show that it is possible to achieve high levels of nitrogen use efficiency through various conservation practices.

One of the conservation techniques is called nutrient budgeting. With this technique, the inputs and outputs of a field are precisely measured in order to make them as balanced as possible. They also monitor nutrients in leaves and soil.

Another technique is called fertigation, in which fertilizer is applied very specifically through the irrigation system. This enables accurate measurement and timing to meet the needs of the plants. The work of the Khalsa team can also be applied to other specialty crops around the world to enable farmers to earn higher incomes in producing nutritious food.

« Matching supply and demand is the basis of the 4R framework with the aim of improving the efficiency of nutrient management, » says Khalsa. “The 4R framework is: The right fertilizer source at the right rate, at the right time, in the right place. That will help us to be more efficient. ”

Understanding how plants like almonds circulate nitrogen year after year and how farmers apply nitrogen fertilizers remains a challenge. Khalsa also says his research highlights the importance of integrating their research with information networks, including certified plant advisors and collaborative expansion.

Efforts to solve these agricultural problems must focus on the wants and needs of farmers, producers and industry associations. This type of work helps promote uptake and create new research opportunities, such as assessing soil health practices in orchards.

Khalsa encourages researchers to stay curious at every step of the food value chain. This allows them to better understand how their research interests align with other scientists, policy makers, and individuals such as consumers in the food and agriculture industries.

« After decades of working with plants, soil and water, I personally think that we can solve the biggest problems by understanding people, » he says. “Agriculture plays an essential role in communities around the world. I can’t find a better way to connect with anyone than through the food we share. ”

Sat Darshan Khalsa is a scientist at the University of California at Davis. This research was funded by the U.S. Department of Agriculture, California Specialty Crop Block Grants, the Foundation for Food and Agricultural Research, the California Department of Food and Agricultural Fertilizers Research and Education Program, and the Almond Board of California.

The American Society of Agronomy is an international scientific and professional society based in Madison, WI. Our members are researchers and trained, certified specialists in the areas of expanding the global food supply and protecting our environment. We work at universities, government research institutions, and private companies in the US and around the world.

Almond, Soil Science Society of America, California, Research