In the wake of today’s deluge of certifications, I am beginning to foresee a new stamp of sustainable approval: “Certified NOT California Grown.” In fact, I’ve already seen one that gets at the point. Namely, a farm touting its beef raised (in CA, nonetheless) without the use of irrigation. Going forward, this low water consumption or irrigation free label will almost certainly gain steam.
To understand the problem, simply Google “salination california.” You’ll quickly see that California farm land is being seriously damaged by irrigation. Most farms use overhead watering (the large sprinklers you can see spraying the crop), which loses an enormous amount of water to evaporation, especially in the California sun. Next, the plant’s roots take up the water and use it to create oxygen during photosynthesis. The notable thing here is mainly what gets left behind – salt. It’s not that farmers are using salt water, but the fresh water (I use the ferm “fresh” loosely because irrigation water can often intentionally contain human waste for fertilizer) will contain a fair amount of salt. As the plants leave the salt behind, it begins to pile up.
There are very few organisms on the planet that can thrive in a relatively high salt environment. The reason? Osmosis, which dictates that water will flow from low solute concentration to high (see diagram below). Thus, in soil with a high salt concentration, water will flow from the plant’s roots back into the soil. The plant will die. Soil with such high salinity becomes useless, and there is already land laying fallow in California for this exact reason.
The root of the problem is that we are growing such a huge volume of food in an area with insufficient rain. In fact, part of the reason that California farmland is preferred is for its high sand content. This means it won’t hold water too long, which the plants will like, provided they soon get another drink (switch the sprinklers on again).
Research is well underway to confer salt tolerance to plants. If some edible plants were genetically modified to better tolerate highly saline soil it would be a temporary fix at best. Most likely it would be a useless and dangerous distraction that provides an excuse to ignore a serious and growing problem.
The solution is to stop relying so heavily on California to grow our food. Major cities must start growing native foods in and very near the city, which will conteniently improve food security (and, as Michael Pollan argued in a letter to President Obama, improved national security). This does mean that the Midwest would have to switch some farmland from corn to plants that are eaten directly, like vegetables. (the vast majority of corn is grown for animal feed or processed products like HFCS.) Few outside the boardroom at Archer Daniels Midland would argue that growing less corn would be a bad thing, and every day new people learn that localization and decentralization of our food production is the only way forward.
