We’ve always had a bit of a soft spot for perennial cereals, eagerly anticipating the day when the Land Institute’s farmer-breeders harvest ready-made muesli from their perennial polyculture on the prairies. Recent research confirms that perennial wheat is slowly coming closer in reality and simply as a concept for conservative farmers to contemplate.
As a concept, it could gain traction in Australia thanks to a desk-study that looked at the economic potential of perennial cereals there. Savings can be made in fertilisers, herbicides, tillage and sowing costs, but are they enough to offset yield penalties? Lindsay Bell and colleagues plugged a perennial wheat into a farm model called MIDAS (Model of an Integrated Dryland Agricultural System). They made various assumptions about the yield penalty that perennial wheat might labour under, the quality of the wheat, and whether it might offer grazing to livestock.
In areas where wheat is in any case not very profitable, then if the quality remains the same perennial wheat is profitable even if the yield is only 60% to 75%. If quality is lower, suitable only for feed markets, then the yield must be at least 85%. Factor in feed and things become even more interesting. On a mixed farm that raises sheep as well as wheat, a dual-purpose perennial grain that offers forage, especially early in the growing season, can “greatly increase whole-farm profitability” according to the study. Even if grain yield is only 40% of annual wheat, a perennial wheat would be worth including on 12% of the farm area. The study points out that “this demonstrates that there is capacity to trade-off grain yield for forage production from a perennial cereal”.1
Other benefits can be factored in too. In some parts of the US, research is focused on perennial wheat because the permanent cover and particularly the root system would slow soil erosion in sensitive areas. Reports of a recent field visit at the University of Michigan, which recently won a US$1 million grant to develop perennial wheat, stress this aspect of a permanent crop. In an aside that article says that “fields could be used to graze livestock between harvests”.
I wonder whether they’re aware of this research thrust on some of the cattle ranches I’ve visited in Texas? Farmers there sow wheat only to provide forage for cattle and don’t really care whether they get a grain harvest from it or not. A half-decent perennial crop would surely be valuable for them.
There are all sorts other factors that could tip the balance in favour of perennial cereals. One that’s become especially relevant lately is carbon sequestration. Those perennial root systems are doubtless capable of plucking buckets of CO2 out of the atmosphere. It would be nice to think that maybe some of the climate change funds sloshing around might find their way into this kind of research and maybe even pay farmers to grow perennial cereals.
- Surely not! That means it doesn’t have to be either or? [↩]