Carbon credit programs for agriculture—which recognize growers' role in removing carbon from the atmosphere and storing it in plants and soils—are continuing to expand, and often in the news. But they aren't the only way that growers can play a role in combatting climate change.
For operations with established sustainability goals, or plans to set them in the future, changes to everyday farming operations can also have an impact. Here's three key climate strategies growers are taking that can benefit the bottom line, too.
1. Cutting back on fossil fuels
The largest source of emission from vineyards and orchards is from fuel and energy use that produces CO2, carbon dioxide.
One option for growers who want to reduce emissions is alternative energy sources. That could mean switching from diesel-powered to electric equipment—even electric tractors.
On a larger scale, it could also mean using solar or wind energy to power irrigation systems. Consistently monitoring and maintaining irrigation systems will ensure efficient energy use as well as help conserve water.
It's also possible for growers to reduce on-farm emissions—and expenses—from fossil fuels even without investing in large-scale changes like these. Planning ahead to minimize tractor passes (with multi-row spraying equipment, if available) or choosing cover crops that don't require mowing are some examples.
2. Optimizing fertilizer uptake
Excess nitrogen applied to crops runs off into ground and surface water or escapes into the air as a gas. Although this accounts for far less of agricultural emissions than fossil fuel use, the impact of nitrous oxide as a greenhouse gas is 300 times that of CO2.
Many growers already manage fertilizer with the goal of minimizing expenses by applying only what will benefit the crop—for example, by using a VRA strategy . But not all are aware the volume of N2O released is impacted by the timing of fertilizer application as well as the amount.
When nitrogen is applied to waterlogged or compacted soils, more N2O is released. N2O emission decreases if nitrogen is applied during periods of active uptake. In a vineyard for example, more nitrogen would be utilized during flowering or post-harvest when roots are actively growing.
3. Promoting soil health
Degraded soil releases CO2, while healthy soil with a high percentage of organic matter stores it. Carbon is lost when soil is disturbed, such as during tillage, or when biomass is removed, such as in pruning. However, carbon can be returned to the soil through decomposition, such as when growers use pruning residue as mulch.
In fact, according to the California Sustainable Winegrowing Alliance, “Agricultural soils are thought to have roughly the capacity to store up to 60-70% of the amount of soil carbon lost during conversion from wildlands ... to agriculture and subsequent crop management systems. If all agricultural lands in the U.S. were managed to enhance soil carbon storage these soils could sequester 75-208 Tg of C.”
In addition to farming practices that return carbon to soil—such as whole orchard recycling—broader efforts to promote soil health have climate benefits, too. The use of cover crops in place of bare fallow ground, in both annual and perennial cropping systems, increases soil carbon storage: a five-year study in vineyards found that soil carbon in a vineyard with a permanent cover crop was roughly 1.4 times greater than in a bare fallow treatment.