Heat waves

Wheat

A recent study has shown that the once in a hundred year heatwaves in the wheat growing area of the Midwestern U.S.A. will soon become 1 in 6 year events. In the wheat growing area of Northeastern China the heatwaves will become 1 in 16 year events.

The study doesn’t look at the impact of water stress on wheat plants but focuses on the heat itself. At around 28°c the wheat plants suffer from heat stress, at around 33°c the heat damages enzymes crucial to the wheat plant’s development.

Because wheat plays such an important role in human nutrition today anything which reduces yields has a major impact, provoking food precarity and famine. A lot of global wheat production is transformed into bread which is seen in economic terms as an inelastic good, demand is only marginally affected by price rises. If prices continue to rise demand doesn’t fall but there will be increasing levels of social unrest which can lead to the overthrow of a country’s government.

Permaculture designers have been warning about the dangers of relyng on too few major crops, such as wheat, rice, corn etc, for decades. We tend to design mixed polycultural systems that produced a diversity of food crops. This diversity is better for human nutrition (recent studies have shown the importance of this for a healthy microbiome) and is also better for biodiversity and system resilience.

The study I mentioned at the begining should provoke some action, it probably won’t but any action will most likely be led by the agro-industries. They have a vested interest in maintaining wheat production and will fiddle with current growing systems and plant varieties to try and maintain production levels. This is most likely doomed to failure and there is still a reluctance in the agricultural world to lookat how agroforestry systems can help ….

Crop yields in alley cropping decreased on average with 2.6% per year over the first 21 years of the tree stand, indicating increasing competitive effects of the trees with their age. On the other hand, studies in traditional Dehesa and Montado systems in Southern Europe showed no negative influence of the trees on crop production, indicating that competition between crops and trees plays a less important role in those systems than in alley cropping. (link)

Other studies have shown that, in some areas, wheat yields are actually up to 19% higher in agroforestry systems (link)

We continue to focus too much on false metrics such as tonnes per hectare. Other studies hav shown that whilst, in some cases, wheat yields are lower in agroforestry systems, grain nutritional quality is higher (link)

For me as a Permaculture designer the study demonstrates the increasingly fragile nature of our current systems and the importance of redesigning them. Carrying all our eggs in one basket has never been a good idea, such a terrible reliance on so few major crops is now and always has been a very bad idea.

The study shows that major change is more urgent than ever, not just increasing the diversity of crops and changing production systems but also taking control of agricultural production away from the agro-industries and their lobbies.