Could the courses return to the Central Valley?
California farmers are struggling to irrigate their crops during the current severe drought. At the same time, they are in the early days of a major longer-term transition that will see them use less water overall to safeguard long-term groundwater availability, under the Water Conservation Act. Sustainable Groundwater Management (SGMA). A significant amount of irrigated farmland in the Central Valley, including many fruit and nut trees, will need to be taken out of production over the next two decades to help balance local groundwater basins. This fallowing will have both environmental and economic consequences. Converting formerly irrigated agricultural land to rangeland, one of its historical uses, is a possible alternative to fallowing. This would maintain the economic productivity of the land and the transition could bring other benefits, including avoiding some of the negative consequences of set-aside.
We spoke with two experts on converting old orchards to pasture: Theresa Becchetti, University of California Agricultural Advisor for Cooperative Extension (UCCE), and Fadzayi Mashiri, County Executive and Natural Resources Advisor at the University of California. ‘UCCE, who work in Stanislaus, Merced and Mariposa counties. They made it clear that establishing functional rangelands on these lands will require coordination, complex decision-making and concerted investment.
Will farmers be interested in grazing their animals in fallow orchards? What would be the consequences of such a transition?
Therese Becchetti: There would certainly be an interest in that. The central valley lacks available pasture and it becomes competitive to find a lease. If there is an opportunity, people will wait to fill it.
Fadzayi Mashiri: The downside is that growers will lose the high economic returns that come from almonds and other orchard crops. These production systems offer up to 10 times more economic returns than rangelands. But if the alternative is fallow, then rangelands have several advantages. They support greater plant diversity, which is really important, especially when it comes to mitigating climate change and ecosystem function and stability. Rangelands also provide habitat for wildlife and impact hydrology. Our research shows that conventional management of almond orchards can lead to soil compaction, which means less rate of water infiltration into the soil.
What are the constraints to the establishment of functional rangelands on formerly irrigated cultivated land?
TB: For the land manager, the big issue is cost. If it’s trees, there’s the cost of uprooting those trees, pruning them, and transporting them offsite or keeping them there. There’s the cost of removing all that black plastic drip irrigation tape. There are infrastructure costs: interior fencing would have been removed. Perimeter fences should probably be rebuilt. And the water troughs should be replaced – they have all been removed from the orchards. The land will likely need inputs to give it more plant diversity and forage options for livestock. One advantage is that the orchards got rid of a predominant invasive grass on the ranges: jellyfish head grass. We could therefore start from a clean slate.
FM: For ecologists, the issue is the integrity of ecosystems. We expect certain rangeland functions, such as plant diversity, water infiltration and wildlife habitat. If the orchards are transformed into rangelands, will we find these functions again? If so, at what level and at what speed? We will definitely have to replant and add more species. We may not have the native grass pastures in the past, but we would bring it closer to that by ensuring that various plant groups are represented.
Do environmental regulations, which aim to protect the integrity of ecosystems, hinder important land use transitions?
TB: For me, it is not so much a question of regulation as of policy. For example, for carbon-smart agriculture programs, the policy requires native perennial grasses on rangelands. But I tried planting natives and failed – we just don’t get enough rainfall. I don’t think you can go back to perennials, even with a lot of inputs and herbicides. Policy changes that would allow more flexibility could help.
FM: You really have to pay attention to the intended use and select the plant species that can respond to it. We need to add enough diversity, including nitrogen-fixing plants, deep-rooting perennials, and annuals suited to the region. This diversity will prevent soil erosion, increase soil carbon and strengthen the stability of ecosystems in the areas we are trying to restore.
What could facilitate the transition from irrigated farmland to rangeland?
TB: We need to focus on paying for things like wildlife habitat and plant diversity; this will help level the playing field a bit. equivalent to the benefit of the orchards. Are there opportunities for other payments for ecosystem services?
What’s the big takeaway picture?
FM: Landscape-scale climate-smart planning and management strategies are needed because all of these landscapes, albeit under different land uses, are connected. Currently, we are going in the wrong direction. A single, well-managed piece of land will not help in these climatic conditions – we need more coordinated, integrated and holistic efforts.