food science sustainability

The promise of perennial grains

There are a handful of crops that feed the world, and corn (maize), rice and wheat are at the top of the list. Hundreds of millions of tonnes of these grains are grown every year. All three are annuals. They are harvested, the land is ploughed over and replanted in the spring.

prairie-grassAs we have known for some time, this is difficult to sustain in the long term. Soil begins to lose its fertility, and we have to compensate with chemical fertilisers. When this runs off, it pollutes waterways and leads to marine dead zones. Ploughing disrupts the soil and risks erosion. And all this harvesting and replanting requires huge amounts of energy.

Grasslands, on the other hand, look after themselves. Nobody replants a prairie. They need no fertiliser or irrigation. Yet many of the grasses on prairies are grain-bearing, year after year, relying on deep roots that access nutrients and hold moisture. So would it be possible to farm perennial grains?

There is a reason why we’ve come to depend on annuals. Because they are replanted every year, our ancestors were able to cross-breed better crops. They lent themselves to selective breeding, and over hundreds of years we managed to nurture several important species into the high yielding crops that have become today’s staple foods. It would have been much harder to have done something similar with perennial grains.

Kansas based organisation The Land Institute believes that it’s not too late to switch tack, and that perennial grains could play a major role in future agriculture. They are working to cross-breed existing food crops with wild cousins, and domesticating perennial alternatives. So far they have tested a perennial wheat-wheatgrass hybrid. It can’t compete with the yields of traditional wheat just yet, but it’s early on in the process. Given another decade or two, and quicker still if we use genetic sequencing, we may have a revolutionary approach to providing our staple foods.

10 comments

    1. Definitely another useful agricultural innovation, especially in developing world contexts. Good for increasing yields and getting more consistent results, but still part of the energy intensive annual cycle.

      Improved seed varieties tend to be developed and marketed by bigger seed companies though, which means some people are worried about corporate involvement in agriculture. Not something I have a problem with as long as farmers have a choice.

  1. Thanks Jeremy – very interesting.
    To widen the issue to our more general diet, have you ever done a feature on Plants for a Future? Ken Fern and others advocate adopting a wider range of plants, for better resilience (and may help nutrition?). http://www.pfaf.org/user/AboutUs.aspx
    I’ve also been enjoying Stephen Barstow’s Around the World in 80 Plants. He grows hundreds of edible species in his garden in Norway, and writes very interestingly about his favourite and most significant edible perennials (many of which are also ornamental).

    1. Yes, all good points – and it certainly shouldn’t be held up as the one big solution, even if the Land Institute claim it. And of course they would, as they’re passionate about it. My view is that it’s an interesting idea, one that will inevitably take decades to investigate. If they do strike gold with it,it could make a valuable contribution.

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